[HN Gopher] Don't send to Gmail over IPv6
       ___________________________________________________________________
        
       Don't send to Gmail over IPv6
        
       Author : croes
       Score  : 144 points
       Date   : 2022-06-03 14:22 UTC (8 hours ago)
        
 (HTM) web link (www.spamresource.com)
 (TXT) w3m dump (www.spamresource.com)
        
       | pcdoodle wrote:
       | Gmail is not Email
       | 
       | We were lucky enough to have a product idea that sold out
       | immediately after some coverage on a few tech sites (A tiny
       | hardware product for nerds).
       | 
       | Trying to update our customers, we sent out an email to about 500
       | people via Shopify, the spot the little guys use to do eCommerce.
       | No links in the email at all, just a text based update that we're
       | here and working hard to keep up with demand.
       | 
       | Ever since then, every email we send to a gmail user (including
       | friends and family) get's bounced. It's not even in their spam
       | box! We have since added google dns txt records and via something
       | they call postmaster tools and we still can't get emails out.
       | 
       | Just text, no links, no phone number, just a product update from
       | a small company.
       | 
       | Gmail is not Email anymore.
        
         | jeffbee wrote:
         | Gmail does not ever "bounce" mail for spam reasons. It either
         | temp-fails the SMTP conversation with a 4xx error code, or it
         | delivers it, to the Inbox or to Spam as indicated.
         | 
         | If Shopify is transforming a temp-fail into a non-delivery
         | receipt, that's their problem, and yours, but nothing to do
         | with Google.
        
         | Avamander wrote:
         | There is not a single provider out there that won't punish you
         | for sending bulk email out of the blue. It's unfortunate you
         | found out like that, but you should try a new domain and let
         | the old one cool down.
        
       | CodeWriter23 wrote:
       | 1-5 mandatory for standing up a mail server on IPv4 ijs
        
       | ale42 wrote:
       | Have a small mail server, pretty low-volume (max bursts are 40-50
       | messages to Gmail, global volume to it is around 100 messages per
       | week), delivering to gmail over IPv6. (Note: DMARC, DomainKeys
       | and SPF all implemented) Mails are delivered reliably and have
       | zero problems with it. Had man more issues with Yahoo, Hotmail
       | and Apple, all of which only accept mail over IPv4.
        
       | alaricus wrote:
       | Don't use Gmail. Here are some better alternatives:
       | 
       | https://proton.me/
       | 
       | https://tutanota.com/
        
         | robjan wrote:
         | I get deliverability issues when sending from Protonmail
        
         | rflrob wrote:
         | It's one thing to advocate not using Gmail for your own mail,
         | and another entirely to advocate not sending any mail to gmail
         | accounts from your own mail server, which is what TFA is really
         | covering.
        
         | Vladimof wrote:
         | Can you search your mail on tutanota yet? Also I wish they
         | would have chose a different name...
        
       | andix wrote:
       | It's totally understandable why a lot of mail providers require
       | correct DNS, rDNS, SPF and DKIM. This is standard in 2022. And
       | DMARC is also not hard to implement, it's just a DNS record.
        
         | zippergz wrote:
         | DNS is not the hard part of DMARC. It's identifying ALL of the
         | legitimate sources of mail from your domain, and keeping up as
         | they change. Easy enough for a hobbyist, but often challenging
         | for even small business.
        
           | andix wrote:
           | Just relay all the mails via your main mailserver and you're
           | done.
        
             | djbusby wrote:
             | I've got two. One primary, corp email system (out/in) and
             | then a second forward-hub for systems to send mails
             | through.
             | 
             | This way one doesn't accidentally bang up the other
        
       | istillwritecode wrote:
       | outlook.com is even worse. If you bring up a mail server, you
       | have to apply to them for permission to send them email. Doesn't
       | matter that you have DKIM, SPF, DMARC, or that the domain is 25
       | years old. They don't care - you must apply through a process
       | that ironically sends email that isn't DKIM certified in their
       | response.
        
       | buro9 wrote:
       | This isn't specific to Google, but IP reputation was used heavily
       | for IPv4... but there either isn't enough reputation for IPv6 or
       | the systems haven't yet scaled to make sense of it (what works
       | for the IPv4 address space doesn't necessarily work for the IPv6
       | address space, i.e. storing and looking up reputation and the
       | slow changes in IPv4 ownership and the rapid burn-through of IPv6
       | ownership).
       | 
       | What people on IPv6 are getting is one of two things: 1) Harsher
       | defaults or 2) No reputation system applied.
       | 
       | In the case of Google for email, it appears that it's harsher
       | defaults.
        
         | onphonenow wrote:
         | My guess is that the defaults are designed to block a similar
         | amount of spam if possible?
         | 
         | Most major mail providers have access to one or more ipv4
         | addresses. This allows for reputation + it's a bit more
         | wasteful to burn through ipv4 blocks on spam campaigns.
         | 
         | ipv6 address are plentiful, so you can burn through them on a
         | spam campaign.
        
           | nybble41 wrote:
           | IPv6 addresses are more plentiful. However, you don't assign
           | reputation to an individual IPv6 address but rather to an
           | IPv6 _network prefix_ (a  /64, or even /60). That gives
           | roughly the same granularity as a single public IPv4 address:
           | one ISP subscriber.
        
             | onphonenow wrote:
             | False, the cost of a prefix is MUCH MUCH lower if you are
             | looking to spam via ipv6.
             | 
             | Total prefixes are 18,446,744,073,709,551,615
        
               | nybble41 wrote:
               | Naturally there are far more IPv6 /60s than IPv4 /32s. As
               | a spammer, though, you don't get to pick just any /60
               | prefix you want--it has to be allocated to you.
        
       | [deleted]
        
       | rascul wrote:
       | Are there any VPS providers who try and help with mail delivery?
       | Perhaps by actively watching for and shutting down spammers, or
       | investigating and taking action when one of their IP addresses
       | show up on a blocklist? Or something else?
        
       | nimbius wrote:
       | SPF dkim and dmarc aren't exclusive to ipv6. I think what the
       | author is bemoaning is just how exhaustive the requirements are
       | to send to one of googles cloistered mailservers in the first
       | place.
       | 
       | check senderbase and the rbls, you might be there too if you're
       | on a less gilded cloud provider like oracle or ibm. in general
       | new mailservers take some TLC to repair the IP space you're given
       | before providers will trust it.
        
       | upofadown wrote:
       | I don't know why everyone lets Gmail off the hook like this.
       | Let's face it, Gmail is broken and has been for some time. It is
       | time to move on.
        
         | Avamander wrote:
         | People have said that for a decade now. Any specific reasons
         | why you're saying this?
        
       | willis936 wrote:
       | (2020)
       | 
       | There is a comment saying it's still true in March 2022.
        
       | Uptrenda wrote:
       | There should be an amendment to the email protocol that routes
       | emails to inboxes if they were paid for by some user-configurable
       | amount. Cryptocurrency would be ideal for this unironically
       | because its basically an open protocol (yeah I know the hacker
       | news crowd hates cryptocurrency but whatever.)
        
       | gorgoiler wrote:
       | One in N of their IPv6 relays is also way more fussy than the
       | others. What's even better for causing frustrating debugging
       | sessions than nebulous spam fighting rules? Intermittently
       | implemented rules.
       | 
       | Google's borglike embrace of email is a sad thing for The
       | Internet that slipped quietly by before it was too late.
        
       | timcavel wrote:
        
       | tenebrisalietum wrote:
       | So what if we just change email to work like this: Mail server
       | will not let incoming messages through unless you've first A)
       | sent a message to that domain AND B) received a reply that
       | doesn't look like an error or bounce.
       | 
       | Yes, you'll have to send an email somewhere with little to no
       | content to initiate reception of things like invoices, password
       | resets, and monitoring emails. Is that such a bad thing?
       | 
       | Yes, spammers will desperately try to get you to send an email,
       | any email, to their domain, or cybersquat on common typos. These
       | problems might have easier and better solutions than letting tech
       | giants takeover a formerly open Internet protocol that anyone
       | should have the ability to use.
        
         | robjan wrote:
         | That's sort of how Gmail does work in my experience. Once there
         | is evidence of an account replying to email from a "less
         | reputable" domain / IP, they tend to let all follow-up
         | correspondence through.
         | 
         | The problem is that people managing their own server wouldn't
         | be able to initiate conversations with people who give them
         | business cards, for example.
        
         | W0lf wrote:
         | That sounds a lot like the idea from Peter Huth's Mail-Terror-
         | Blocker PRO, a theater drama studied guy that happened to
         | become an _internet expert_ by accident here in Germany back in
         | the 2000s. Unfortunately, his program failed in the most
         | hilarious ways and quickly became a joke in the usenet groups
         | back in the day.
        
           | konschubert wrote:
           | I don't know the guy, but what's the problem with somebody
           | being theater drama studied?
           | 
           | Like somebody can't be an expert at something without having
           | gone through formal education for it?
        
             | W0lf wrote:
             | Nice framing. However, I was rather thinking about the
             | _drama_ he created back then with his software due to a
             | logical error. To me it had some resemblance of a nice play
             | at the time.
        
         | mgoetzke wrote:
         | How would the first mail come through ?
        
           | zerocrates wrote:
           | They're saying you, the would-be recipient of later messages,
           | would have to initiate by sending a message.
        
             | Closi wrote:
             | Yeah, but then the other persons mailbox will reject you
             | because they haven't messaged you yet.
        
           | Closi wrote:
           | Well I guess you could base it on some sort of reputation
           | system...
        
           | bombcar wrote:
           | Yeah, if _every_ single mail server worked that way, you
           | couldn 't ever get off the ground.
        
       | ldiracdelta wrote:
       | Phew!! Glad he isn't lying with that title.
        
       | bhauer wrote:
       | The annoying thing about the major email services (Gmail,
       | Outlook, et al) using reputation as a key input in their spam
       | prevention algorithms is that they don't handle reputation in a
       | way sympathetic to small and hobbyist mail server operators at
       | all.
       | 
       | Google and Microsoft have the computation and data storage
       | resources to forever record how much spam they've received from
       | the mail servers operated by any given small company or hobbyist.
       | If a domain's authoritative mail servers have a history of never
       | sending spam, when that company or hobbyist (for any reason) has
       | to switch hosting providers and gets a new IP address,
       | Google/Microsoft should recognize that the domain, and its
       | referenced mail servers, has never been malicious.
       | 
       | But instead, the majors treat a new IP address for a long-
       | established domain as entirely new to the internet and assign it
       | zero, or even negative, reputation. And they don't care to
       | address this because, well, why care about hobbyists and the rare
       | small company insolent enough to try to self-host email?
        
         | w-j-w wrote:
        
         | YetAnotherNick wrote:
         | I could bet that most of mails from new IPs are spam because
         | there are much fewer people willing to set up a mailserver than
         | there are spammer operated mailservers. It is cheap to buy a
         | new IP(comes free with many $2 hosting plans). The problem of
         | identifying if a new IP is used for spam is not easy to solve.
        
           | megous wrote:
           | > The problem of identifying if a new IP is used for spam is
           | not easy to solve.
           | 
           | Huh? With dataset of ~100k classified hams/spams I get like
           | >99% precisison in identifying spam/ham with just bogofilter
           | and 0 heuristics whatsoever (my mail server accepts
           | everything, and I just use bogofilter client side).
           | 
           | I guratanee you MS has a dataset with > 100k emails, lol.
           | 
           | It's not like this is unsolved problem.
        
             | SoftTalker wrote:
             | Right. While at the same time as they clumsily block any
             | IPs with unknown reputation, they seemingly cannot reliably
             | flag a poorly formatted, obvious and well-known fake
             | invoice for "Norton 360 renewal" as spam (and really, it's
             | worse than spam, it's a scam).
        
             | Avamander wrote:
             | > It's not like this is unsolved problem.
             | 
             | My god, are you joking or what? Spam, a solved problem? Far
             | from it.
        
               | SoftTalker wrote:
               | Why can I identify spam at a glance, with greater than
               | 90% accuracy, from the subject line alone, and to Google
               | it's an unsolved problem?
               | 
               | Google reads and indexes every email that they deliver to
               | a gmail inbox. They probably have the worlds largest and
               | highest paid staff of ML experts, and they resort to
               | auto-flagging based on IP address?
               | 
               | Fix it.
        
               | Avamander wrote:
               | > to Google it's an unsolved problem?
               | 
               | It's an unsolved problem for anyone.
               | 
               | > Why can I identify spam at a glance, with greater than
               | 90% accuracy
               | 
               | I don't think you understand how terrible even 99.998%
               | accuracy is at their scale.
               | 
               | > They probably have the worlds largest and highest paid
               | staff of ML experts, and they resort to auto-flagging
               | based on IP address?
               | 
               | You think they aren't using them for this? IP addresses
               | very likely go into their model as well, when determining
               | something is spam.
               | 
               | > Fix it.
               | 
               | They are and adversaries are breaking them again.
        
               | kingjojo23 wrote:
               | > I don't think you understand how terrible even 99.998%
               | accuracy is at their scale.
               | 
               | What does scale have to do with it, am I missing
               | something? Wouldn't a spam detection rate of 99.999% mean
               | that only every 100000th spam mail would get through on
               | an account basis, how's that terrible?
        
               | Avamander wrote:
               | > What does scale have to do with it, am I missing
               | something?
               | 
               | The person I replied to said they can identify spam with
               | 90% accuracy with a glance, my point was that it's
               | abysmal as accuracy. Even orders of magnitude better it'd
               | still be bad.
               | 
               | > Wouldn't a spam detection rate of 99.999% mean that
               | only every 100000th spam mail would get through on an
               | account basis, how's that terrible?
               | 
               | I didn't specify if it's per-account or a false positive
               | rate, it's also actually not relevant to the point I'm
               | trying to make.
               | 
               | When you receive billions of letters a month small errors
               | start to matter and they're doing a better job than the
               | person I replied to thinks they do.
        
           | bhauer wrote:
           | > _The problem of identifying if a new IP is used for spam is
           | not easy to solve._
           | 
           | How is it not easy to check a reputation database for
           | _domains_ when evaluating a mail server?
           | 
           | Using DKIM records, Google could cross-reference the
           | reputation for the sending domain and, where applicable,
           | recognize that the domain in question has never been
           | malicious or negligent. And in that case, extend a
           | probationary reputation sufficient to allow the IP to
           | establish its own new reputation.
        
         | ipaddr wrote:
         | The really annoying thing these days is google blocking zip
         | files as spam requiring you to use google drive.
        
           | rstupek wrote:
           | Zip files are being used to infect computers with malware
           | which would explain why they're blocking them
        
             | DarylZero wrote:
             | I guess they're not allowed on Google Drive either.
        
         | walrus01 wrote:
         | they are basing their filters on the reputation of the netblock
         | that your individual ipv4 /32 (or ipv6 equivalent) is contained
         | in. And very often when you are hosting with a low cost VM or
         | VPS provider the historical record of _other_ IPs operated by
         | the same hosting company in the same  /24 or something is very
         | poor.
         | 
         | while I concur with all of the points you make, there is a
         | logical and statistically accurate reason for some of these
         | spam filters.
         | 
         | even if your no-open-relay, rdns, spf, dkim, dmarc, SSL/TLS and
         | other configuration is absolutely impeccable on your smtpd,
         | your only recourse in a situation like this is to change to a
         | new ISP that does not have a poor IP space reputation in all
         | the adjacent IPs.
        
           | Neil44 wrote:
           | The netblock thing has happened to me. My Linode that I've
           | had sending mail for 6 years gets blacklisted now purely for
           | being on the netblock that it's on.
        
             | apocalyptic0n3 wrote:
             | Yep. I've encountered the exact same issues on multiple
             | Linode servers in multiple data centers. I've also
             | experienced it with an AWS server. It's often almost
             | impossible to get it unblocked because the support teams at
             | the email providers (if you can even contact them) don't
             | realize that's what's happening. I didn't understand it
             | myself until I got a call with an engineer at Microsoft who
             | realized it in the middle of our call. He unlisted us on
             | the call and we were fine for a while, but were eventually
             | blocked again and haven't been able to get unblocked. It's
             | really frustrating and I'm slowly ending all of my email
             | services (both professional and hobby) as a result.
        
         | hamburglar wrote:
         | Indeed, although I think there is a little more rationale than
         | simply not caring. The hobbyist/small mail server is
         | historically more likely to go unpatched and pwnage is more
         | likely to go unnoticed, so it's unfortunately a good defensive
         | move to penalize them reputationally by default.
         | 
         | PS yahoo is the worst for assuming poor reputation from a
         | sender. In my experience they just introduce massive delivery
         | delays at the drop of a hat even when the sender has a stellar
         | reputation.
        
           | alxlaz wrote:
           | > I think there is a little more rationale than simply not
           | caring.
           | 
           | You're right in one more way: both Google and Microsoft offer
           | email hosting solutions for small businesses. Their main
           | (and, if you've got more than 8-10 accounts or so, the only)
           | selling point is that it makes managing email hassle-free.
           | Making it as painful as possible for small businesses to host
           | their email server helps these services tremendously. If they
           | had real interoperability (either of their own accord or
           | because it were forced upon them through regulatory
           | measures), the biggest cash cows of these services --
           | companies that are well into "enough accounts that your own
           | server would be much cheaper" territory but not large enough
           | to afford or risk large infrastructure changes -- would
           | evaporate pretty quickly.
        
           | bhauer wrote:
           | > _The hobbyist /small mail server is historically more
           | likely to go unpatched and pwnage is more likely to go
           | unnoticed, so it's unfortunately a good defensive move to
           | penalize them reputationally by default._
           | 
           | But to reiterate my earlier point: Google and Microsoft have
           | the computational and storage capacity to have a detailed
           | history of all domains' authoritative mail servers behavior.
           | They will know whether a domain has a history of patch
           | negligence.
           | 
           | No, I think the far simpler explanation is that they just
           | don't bother tracking reputation by domain. Or if they do,
           | it's largely overshadowed by the weight given to IP-based
           | reputation.
        
             | hamburglar wrote:
             | Oh, I'm not saying you're wrong. They absolutely could put
             | the effort in to solve this problem.
        
         | gnarbarian wrote:
         | This seems like a major legal liability for Google. It could be
         | shown that Google and other major email hosting providers act
         | like a cartel by unfairly discriminating against companies who
         | don't use a major email provider.
        
           | nonameiguess wrote:
           | They hurt more than competitors. If anyone from gmail is
           | reading and gives a crap about the collateral damage from
           | policies like these, they have set me back at least a few
           | months in my attempts to adopt a child. The agency my wife
           | and I had been getting licensed through dropped us, citing
           | lack of responsiveness in completing paperwork. But I've been
           | e-mailing them for months with questions clarifying how to
           | fill out unclear forms and they've been ignoring me. I
           | presented them with a history of all the sent e-mails they
           | never answered, and even gave my e-mail address in person
           | last time I was there, asking them to add me to an allow-
           | list, but it didn't make any difference.
           | 
           | It's particularly disappointing because even just getting the
           | process started was delayed when no one answered our initial
           | inquiries of interest for nearly a month. That was when I
           | first figured out it was because my e-mails were getting
           | routed to the agencies' spam folders. At this point, I'm
           | probably just going to have to give in and get a gmail
           | address for the sole purpose of completing an adoption, and
           | then stop using it and go back to my real address.
           | 
           | Who'd have thought this would be the thing preventing me from
           | completely de-googling?
        
             | superasn wrote:
             | My loss isn't as big as this but I've gotten some Paypal
             | disputes because those users didn't get any of the welcome
             | emails (for a rather costly purchase). My issue has been
             | more with Apple's mail for some reason though.
             | 
             | Thankfully all my customers have been super understanding
             | and were kind to take the disputes back once they were able
             | to locate the emails in the Spam folder. Also I finally
             | decided to just use a "reputed" smtp server to fix my
             | problems (feels like extortion but what can you do).
             | 
             | I've written this before, but it's so sad that something so
             | important and vital like email is so broken and we are the
             | mercy of corps like Google/Apple/Microsoft and everyone has
             | their own secret policy.
        
             | dorfsmay wrote:
             | Hiding messages in a spam folder is essentially ghosting.
             | Email servers should reject messages that they consider
             | spam.
             | 
             | I've run into countless problems because of my messages
             | being marked as spam. The worse is that now it as become
             | socially acceptable to ghost people, I never know who
             | ghosted me, the mail server or the person! I've run into "I
             | ignore your email, get the hint" a few times when thinking
             | I was marked as spam and tried to contact people through
             | other means.
        
               | rascul wrote:
               | Too many false positives to reject everything they
               | consider spam.
        
           | jawr wrote:
           | I think everyone always looks at it from the perspective of
           | the hobby mailer, when instead gmail looks at it from the
           | recipients point of view.
           | 
           | It's really really trivial to automate buying a domain, get
           | some IPs and setup DKIM, SPF and DMARC. How can a provider
           | determine intent?
           | 
           | Gmails approach is to mostly use user signals, which in my
           | opinion is the best way.
           | 
           | At a company I've worked for, they sent some mail using
           | sendgrid to a poorly made mailing list and we're in gmail
           | spam for ages.
           | 
           | My personal ran email mostly stays in inbox.
        
           | alar44 wrote:
           | Sure, then they relax things, spam explodes, and people are
           | going to complain that they're not doing enough to fight spam
           | or actively enabling it.
        
             | throw10920 wrote:
             | Google has _more_ than adequate capabilities to handle
             | spam, as several comments point out above. Also,
             | Hashcash[1], which is a virtual silver bullet for email
             | spam, _especially_ when combined with existing trust
             | mechanisms (i.e. the less reputation you have, the harder
             | the Hashcash challenge).
             | 
             | The problem is _not_ that the level of strictness that
             | Google is applying is necessary to reduce spam; the problem
             | is that Google doesn 't care and is in fact incentivized to
             | _not_ accept email from non-Google domains.
             | 
             | [1] https://en.wikipedia.org/wiki/Hashcash
        
               | Avamander wrote:
               | > Google has more than adequate capabilities to handle
               | spam, as several comments point out above.
               | 
               | Yes, and sender reputation is part of it :D that's why
               | they can handle it.
               | 
               | > Also, Hashcash[1], which is a virtual silver bullet for
               | email spam, especially when combined with existing trust
               | mechanisms
               | 
               | Who do you think has to and can spend more compute or
               | money, well-trusted Google or a small player? Far from a
               | silver bullet.
               | 
               | > i.e. the less reputation you have, the harder the
               | Hashcash challenge
               | 
               | Who do you think will have better reputation? I won't
               | even start at how different people define spam. Though, I
               | can promise you that on average SpamChimp would get to
               | send a lot of spam for much less "HashCash" than a small
               | player.
               | 
               | > is in fact incentivized to not accept email from non-
               | Google domains.
               | 
               | Everyone is.
        
               | sigstoat wrote:
               | > Who do you think has to and can spend more compute or
               | money, well-trusted Google or a small player? Far from a
               | silver bullet.
               | 
               | i'm not even a big fan of hashcash, but i don't think you
               | understand it, or how it could fit in as a component of a
               | broader spam mitigation system. (for better or worse)
               | 
               | google wouldn't need to compute hashcash for their
               | outgoing emails, because they have DKIM and a solid
               | reputation. nor is its computational power somehow at
               | odds with that of smaller players.
        
               | Avamander wrote:
               | > i don't think you understand it, or how it could fit in
               | as a component of a broader spam mitigation system.
               | 
               | It's not that I don't understand, I know how it won't.
               | 
               | > google wouldn't need to compute hashcash for their
               | outgoing emails, because they have DKIM and a solid
               | reputation.
               | 
               | Great, so what's the point? Small players would have to
               | pay Google to deliver mail :D
               | 
               | > computational power somehow at odds with that of
               | smaller players.
               | 
               | As I said in my other comment, either botnet devices can
               | send tens if not hundreds of spam letters, or it's going
               | to be slow and/or expensive for all the legitimate small
               | senders. You really can't have both.
        
               | BenjiWiebe wrote:
               | The thing with hashcash is that a small player _doesn 't
               | need_ much compute power, cause they aren't sending a
               | million emails a minute.
        
               | Uptrenda wrote:
               | Hashcash is an interesting idea and very creative. But I
               | do think you're right. It may impose reasonable limits on
               | a single computer. But if an attacker has a botnet they
               | can still send out a crap load. Botnets and spam
               | practically go hand-in-hand as-is, so I don't see how
               | hashcash helps there.
               | 
               | Still... it is a creative idea.
        
               | Avamander wrote:
               | Oh, so it's ineffectual against spam, got it.
               | 
               | Either botnet devices can send tens if not hundreds of
               | letters, or it's going to be slow and/or expensive for
               | all the legitimate small senders. You really can't have
               | both.
        
               | tzs wrote:
               | > Yes, and sender reputation is part of it :D that's why
               | they can handle it.
               | 
               | They aren't doing a very good job of using sender
               | reputation. If you have a domain with a several year
               | record of no spamming whatsoever, and with every outgoing
               | message using DKIM, they will still start blocking you if
               | _other_ _senders_ who just happen to have an IP address
               | close to yours start spamming.
               | 
               | IP block reputation should only be used to set the
               | default when dealing with new senders. If they have seen
               | enough DKIM signed messages from a sender to know that
               | the sender has a good reputation, IP block reputation
               | should have weight 0 when receiving mail from that
               | sender.
               | 
               | Google could do this without any increase whatsoever in
               | the amount of spam that shows up in their customers'
               | inboxes. All that would change is that their false
               | positive rate would go down.
        
               | Avamander wrote:
               | > They aren't doing a very good job of using sender
               | reputation.
               | 
               | That's your limited perspecive, sorry.
               | 
               | > they will still start blocking you if other senders who
               | just happen to have an IP address close to yours start
               | spamming.
               | 
               | Absolutely, how would they know how that provider assigns
               | those IP's? A lot of spammers use entire /24's.
               | 
               | > If they have seen enough DKIM signed messages from a
               | sender to know that the sender has a good reputation
               | 
               | A lot of spammers have DKIM, it's not a good reason to
               | allow mail from a suspicious subnet.
               | 
               | Pick a provider that deals with their spam complaints.
               | That's the harsh truth.
        
           | amenod wrote:
           | I hope so! I am tired of explaining people that it's actually
           | Google's fault they didn't receive my mail. I'll be happy
           | when they pay dearly for the disservice they do to e-mail.
        
             | Avamander wrote:
             | It's not really Google's fault to be honest. The need to
             | warm up new IP's has existed for a while and a lot of
             | providers do it. Any postmaster with experience knows how
             | and why it's done.
        
               | black_puppydog wrote:
               | The root comment literally explains that that's BS.
               | 
               | Every post master knows _that_ it is done. But it doesn
               | 't have to be that way, although it certainly can feel
               | like it when a company like google decides to not budge
               | on the matter.
        
               | Avamander wrote:
               | > But it doesn't have to be that way
               | 
               | Sure, if you want spam. Don't like it, get people to
               | deploy DKIM, then the domains will be used for reputation
               | purposes.
               | 
               | What the root comment says is BS, the industry uses these
               | methods for a very real and practical reasons.
        
               | tomatocracy wrote:
               | Even if you have DKIM, SPF and DMARC all set up, at least
               | Microsoft still seems to give a decent weight to IP
               | reputation and assign a negative reputation to
               | unknown/low use IPs.
        
               | Avamander wrote:
               | Absolutely, my second sentence says how that could
               | change.
               | 
               | I would have thought that it's fairly self-explanatory
               | that anti-spam measures utilize the strongest signals. If
               | sender domain becomes that, it will get more weight.
               | 
               | So if in the future email providers could reject both
               | SPF-less domains and DKIM-unsigned letters, IP's would
               | definitely become less relevant. So, get people to deploy
               | those things.
        
               | BenjiWiebe wrote:
               | No, it can be a different way and still not have spam, by
               | trusting/tracking domains instead of IP addresses.
        
               | Avamander wrote:
               | I did write how using domains for reputation purposes
               | instead could happen. The second sentence.
        
               | cmroanirgo wrote:
               | DKIM in no way helps to get past the cartels'
               | "reputation" filters. I send maybe one email every few
               | months to microsoft accounts & it's always received as
               | spam. My server setup & ip have been solid for a decade.
               | It's only ever the globalist providers that block me.
               | Google is 50/50 I get through. Everyone else (eg
               | Protonmail) is no problem.
        
               | Avamander wrote:
               | It absolutely does. Also that was an "if, then
               | potentially" sentence about reputation tracking in the
               | future.
               | 
               | In your case, it's likely that your volume and sending
               | patterns aren't consistent and trustworthy enough to keep
               | track of your domain and IP reputation.
               | 
               | You have to understand that they get millions of letters
               | from new domains each day, sent from compromised
               | Wordpress blogs and the alike. If you want to be
               | deliverable, you have to be consistent and not
               | suspicious.
               | 
               | Or, more likely, there's some other mistake in your
               | configuration somewhere.
        
               | ghshephard wrote:
               | You also wrote:                   The need to warm up new
               | IP's has existed for a while and a lot of providers do
               | it. Any postmaster with experience knows how and why it's
               | done.
               | 
               | I think the point people are trying to make, and I'm
               | sympathetic to, is that if an ultra-low volume email
               | poster, with a full-set of SPF DKIM and DMARC credentials
               | configured _and_ zero history of sending spam - that the
               | majors (Yahoo /Google/Microsoft) could start off by not
               | sending email from that domain immediately to spam, just
               | because it isn't a well established and trusted IP
               | address.
               | 
               | Alternatively - come up with something akin to D&B
               | registration system so people can attest that they won't
               | engage in spammy behavior.
        
               | Avamander wrote:
               | > I think the point people are trying to make [...] not
               | sending email from that domain immediately to spam, just
               | because it isn't a well established and trusted IP
               | address.
               | 
               | Yes, and I'm saying what's the prequisite for that to
               | happen. As long as it's okay (which it currently is) to
               | send unsigned mail, IP addresses have larger weight. DKIM
               | needs more deployment for that to change.
               | 
               | There's absolutely no way that IP-based reputation
               | schemes will be deprecated before alternatives are
               | viable. Sure it would be nice for a few people here, but
               | no, won't happen before the ecosystem improves.
               | 
               | > Alternatively - come up with something akin to D&B
               | registration system so people can attest that they won't
               | engage in spammy behavior.
               | 
               | Already exists. That too gets abused.
        
               | denton-scratch wrote:
               | It's cheaper and easier to munch through lots of
               | throwaway domains than to keep moving IP neighbourhoods,
               | isn't it? I don't know - is free domain tasting still a
               | thing?
               | 
               | If you filter by IP block (or address!), it might be a
               | block that has changed hands and is no longer spammy. Or
               | it might be a block from the Zen Policy Blocklist, which
               | blocks ranges that the responsible ISP has submitted as
               | domestic or retail blocks that are supposed to send
               | outbound mail through the provider's smarthost.
               | 
               | If you filter by domain, that could be the envelope
               | sender, the From:, the Reply-to:, or the domain of the
               | SMTP client. Only the last is reliable; and you also have
               | the IP address for the client. In my experience, the IP
               | address is more useful, for longer, than the domain name.
               | But any good blocklist should age quickly (i.e. old stuff
               | should drop off the list).
        
               | Avamander wrote:
               | > It's cheaper and easier to munch through lots of
               | throwaway domains than to keep moving IP neighbourhoods,
               | isn't it?
               | 
               | Depends on your approach. If you hack IoT devices then
               | you have a lot of IP's. If you hack Joomla sites, you
               | have a bunch of domains.
               | 
               | > I don't know - is free domain tasting still a thing?
               | 
               | Yes. There are also discounts and stuff like that.
        
             | gnarbarian wrote:
             | Are you using S/MIME certificates?
        
               | smartbit wrote:
               | Why are you asking? Is there a relation between spam
               | handling and usage of S/MIME?
        
               | Kadin wrote:
               | Last time I looked into it (I run a mailserver and
               | mailman list for one of my hobby groups), S/MIME wouldn't
               | change your "spamminess" reputation score.
               | 
               | DKIM, DMARC, and SPF do, though, and basically are table
               | stakes if you want your mail (especially mailinglist
               | messages) to go through to people at major providers.
        
         | ajross wrote:
         | > If a domain's authoritative mail servers have a history of
         | never sending spam, when that company or hobbyist (for any
         | reason) has to switch hosting providers and gets a new IP
         | address, Google/Microsoft should recognize that the domain, and
         | its referenced mail servers, has never been malicious.
         | 
         | That algorithm doesn't work. The internet is filled with parked
         | domains that have "never been malicious". This just creates a
         | new market for clean domains that you can use to evade
         | protections. It makes spam a little more expensive, but it
         | still gets through.
         | 
         | None of these tricks work. There are no tricks. All rules can
         | be gamed. The only thing that can't be easily faked is reality:
         | if Microsoft knows you're a big org with a well-managed IT
         | group running your output email setup, then they know they can
         | (probably) trust you not to spam their customers. If you are
         | too small to prove that to MS in a scalable way, no amount of
         | heuristic trickery is going to help you.
        
           | bhauer wrote:
           | I'm sorry, but I don't buy that argument.
           | 
           | Google--a technology giant with algorithms and heuristics
           | running most operations--is not up to the task of improving
           | algorithms for email server reputation? No, they are
           | definitely capable of improvement. It's simply not of
           | interest to them.
           | 
           | I can hardly blame them because the cost-benefit analysis
           | clearly says, "why bother?"
           | 
           | Of course anything can be gamed, but magnitude matters. I've
           | had the same domain for 24 years, with many hundreds or
           | thousands of email conversations between users of my server
           | and those of the major email players over the years. I had to
           | switch my mail server's IP address two years ago. Immediate
           | zero reputation from many big players.
        
             | Avamander wrote:
             | > is not up to the task of improving algorithms for email
             | server reputation? No, they are definitely capable of
             | improvement. It's simply not of interest to them.
             | 
             | Incorrect, if they stopped spending all that money and
             | effort to keep up, their users would get flooded.
             | 
             | > Of course anything can be gamed
             | 
             | Sending spam/marketing e-mails is a multi-million industry.
             | Both on illegal and legal markets. It's a constant race.
        
           | BenjiWiebe wrote:
           | Parked domains also don't have a record of sending good
           | emails either.
        
             | ajross wrote:
             | Tough love: neither do our vanity domains (and yes, I have
             | one too, and feel the same pain trying to get gmail to take
             | mail). No one is going to pay someone to dig through our
             | decades of mailing list activity trying to figure out
             | whether to let a half dozen replies through.
             | 
             | This isn't the 1990's anymore, recipient domains aren't
             | just homes to a few hundred undergraduates or a dozen
             | programmers. Email hosts manage communication for hundreds
             | of millions of customers.
        
         | kevincox wrote:
         | FWIW I run a service that sends a decent amount of email to
         | GMail users. While it was a bit slow to get started (messages
         | being marked as spam) once I had sent for a month or two and
         | had a few users that marked the messages as not-spam I don't
         | appear to have any problems. I say this sending from a Digital
         | Ocean IP address that occasionally changes. It appears that
         | Google highly values domain reputation and that once I have got
         | onto their good list I am doing OK.
         | 
         | Disclaimers: I make sure to do everything else right. I have
         | SPF and DKIM and my DMARC policy is to reject 100%. I also
         | don't use IPv6 (DO Kube doesn't really support IPv6 well).
         | 
         | I have found other major providers to be much worse. Microsoft
         | seems to rely almost entirely on IP reputation and marks
         | everything as spam, even accounts that have marked messages as
         | "not spam" many, many times. Apple outright blocks the IP
         | range.
        
           | AshamedCaptain wrote:
           | My experience is that all of SPF, DKIM and DMARC are almost
           | completely ignored by Gmail -- one day I simply stopped DKIM
           | and DMARC and Google keep happily accepting emails (and to
           | this day I still send emails without). In fact they will
           | happily accept emails even when the SPF check didn't pass and
           | the policy clearly says strict reject aka -all .
           | 
           | While on the other hand I fully agree with TFA: I have
           | _never_ been able to send an email to Gmail from a IPv6
           | address and have it not end up as spam, not even to accounts
           | where I already whitelisted previous attempts.
           | 
           | I don't think it's a reputation issue, since my IPv4
           | addresses likely have much worse reputation. It's as if they
           | just handicap all IPv6 addresses.
        
             | kevincox wrote:
             | GMail definitely respects my DMARC reject policy. But IDK
             | how missing one of SPF or DKIM affect its spam decision.
             | But with DMARC reject and both missing or invalid it will
             | bounce the message every time I have seen.
        
               | tomatocracy wrote:
               | Automatic mail forwarding without altering the From
               | address will cause DMARC alignment for SPF to break. This
               | is a common enough legitimate setup that most providers
               | seem to effectively downgrade the DMARC policy applied
               | when they see this (usually reject becomes quarantine,
               | quarantine becomes ignore).
        
           | marcosdumay wrote:
           | > sends a decent amount of email to GMail users
           | 
           | That's why your experience does not apply to the GP.
        
           | andix wrote:
           | My experience with digital ocean was, that their IP subnets
           | have a horrible reputation for email. Google is easy, but try
           | to get unblocked from Microsoft (office 365 or hotmail). In
           | the end I switched to another provider.
        
             | tzs wrote:
             | The only thing I found that seemed to help with Microsoft
             | is for the recipient to find the mail in the spam box and
             | reply to it.
        
         | bombcar wrote:
         | Back when domains were easy to spoof (I could setup a server
         | and send mail as ycombinator.com easily enough) it made sense
         | to track the IPs, but now that you have DKIM and SPF links to
         | cross-check, you _should_ be able to use the domain reliability
         | as a strong indicator. Sure you would have to catch people
         | buying a  "good" domain that expired, but that shouldn't be an
         | insane hurdle.
         | 
         | The real story is nobody cares.
        
           | bhauer wrote:
           | > _The real story is nobody cares._
           | 
           | Exactly. Why should the major players care about those too
           | small to matter?
           | 
           | > _Sure you would have to catch people buying a "good" domain
           | that expired_
           | 
           | Adding to my earlier point, Google and Microsoft are well-
           | enough connected to the domain registrars to know when that
           | scenario has happened as well. If they put any effort into
           | it, they could reliably determine whether a new IP address
           | for an established domain is legitimate or a fraud. But as
           | we've said, why put any effort into it when the only people
           | complaining are not important?
        
             | bombcar wrote:
             | And it's even worse - if we theorize a email competitor
             | appearing out of nowhere to rival Gmail, and people
             | complaining, all that would happen is Google and Microsoft
             | would special-case that provider, and the underlying issue
             | wouldn't be solved.
        
               | gnarbarian wrote:
               | a class action lawsuit could make them care.
               | 
               | as far as how to solve this problem technically, I think
               | a reputation system based not on domains or ips but on
               | email certificates is the real answer here.
        
               | toast0 wrote:
               | DKIM is certificates, so I'm guessing you're talking
               | about sender certificates?
               | 
               | How would that help? Spammers can get certificates too.
               | Maybe it cuts down on some of the misconfigured http
               | email senders, maybe, but not enough to matter. Scam
               | sites run https these days.
               | 
               | You can't use like age of activity of the cert to help
               | because a) things get compromised, b) you need to rotate
               | your certs frequently anyway.
        
               | u801e wrote:
               | Shouldn't the authority (or key) used to sign those certs
               | be long lived? The certificates themselves should be
               | rotated frequently, bit not the key used to sign them.
        
               | Avamander wrote:
               | There's only S/MIME, TLS and BIMI+VMC that use actual
               | certificates.
               | 
               | DKIM does not and DKIM keys should be rotated once in a
               | while, but few do.
        
               | Avamander wrote:
               | Being able to tie together letters and senders, knowing
               | who sent what, would help.
               | 
               | It wouldn't help to fully trust, nothing would, it's a
               | human problem, it would help to trust more.
        
               | toast0 wrote:
               | If the email is DKIM signed, it's expected that the
               | sender was authorized to send the message.
               | 
               | Any wide spread certificate program will just have the
               | email address as the identity, and it will be authorized
               | by establishing control of the email (just like the
               | majority of certificates used for https are domain
               | control only, no organizational verification, not that
               | organizational verification means much anyway). Anyway,
               | identity is hard; there are many people with my name,
               | including a Pulitzer winning author.
        
           | tshaddox wrote:
           | Isn't the problem more about how to treat brand new domains
           | the first time you encounter them? In order to be friendly to
           | small/new email servers, you would presumably need to
           | initially grant new domains a sufficient reputation for them
           | to send mail reliably. But since domains are essentially
           | unlimited, a bad actor can trivially circumvent your
           | reputation system by spinning up endless domains. This seems
           | like a fairly textbook example of a Sybil attack.
        
             | marcosdumay wrote:
             | Spinning up endless domains is something that can be
             | detected perfectly well. Very few entities can do it in a
             | way that interferes with other people.
        
             | DarylZero wrote:
             | Domains aren't free, they're limited.
        
               | Avamander wrote:
               | Keep in mind that there are a lot of domains out there
               | without SPF records, there's really no lack of domains to
               | abuse.
               | 
               | Not to mention all the websites that get hacked or the
               | uber-cheap registrars.
        
           | toxik wrote:
           | Using DKIm you don't actually have the problem that people
           | can buy so-called good domains, because the system works with
           | private and public keys, so not only do you need a good
           | domain, you also need the private key for that specific DKIM
           | in signature
        
             | bombcar wrote:
             | I wonder how many systems actually track DKIM signatures
             | over time, beyond just checking at the moment of email
             | receipt.
        
               | Avamander wrote:
               | Most, check results are usually kept in the final stored
               | letter.
        
               | BenjiWiebe wrote:
               | You wouldn't need to.
               | 
               | At the point of receipt, when verifying via DKIM that
               | foobar.com did indeed send this email, then update your
               | spam statistics for foobar.com and you're good.
        
       | telmich wrote:
       | The article has nothing to do with IPv6.
        
         | bri3d wrote:
         | The whole point of the article is that Google's sender identity
         | scoring system is more strict when the sending IP is an IPv6
         | one. That's a pretty clear cut link to IPv6, no?
        
           | telmich wrote:
           | Let me rephrase: the whole article is equally valid for IPv4.
           | Being more or less strict is a claim the article makes
           | without proof. And as far as my experience goes, there is no
           | difference.
           | 
           | So standing by it: the article has nothing to do with IPv6
           | per se.
        
           | bragr wrote:
           | Google is really strict in general about these kinds of
           | things. I had to go a few rounds with my VPSes before emails
           | from them would consistently not end up in spam, but looking
           | at the headers I'm mostly using IPv6 so I don't draw the
           | conclusion "don't use IPv6" just "if you have IPv6, which is
           | more likely than not now, be careful and read the docs"
        
         | m348e912 wrote:
         | Huh? I'm not even sure how you came to that conclusion.
         | 
         | Gmail is probably tougher on mail servers using IP6 addresses
         | because they're plentiful and I suspect spammers were having a
         | field day setting up temporary mail relays forcing google to
         | play whack-a-mole.
         | 
         | I used to run my own email server years ago but spam and spam
         | protection measures have made it time consuming and annoying.
         | I'll leave it to the professionals.
        
       | kazinator wrote:
       | Don't send to Gmail over IPv6.
       | 
       | .... Unless you're a kooky spammer re-sending a captured YouTube
       | terms-of-service-change e-mail to the inbox of some Gmail user
       | who bears no relation to the original recipient of that e-mail.
       | 
       | Then, hey, you have no issues with delivery.
       | 
       | https://news.ycombinator.com/item?id=31577087
        
       | jeffbee wrote:
       | Gmail has stricter requirements for v6 because they assume if you
       | are using v6 then they can leave aside all the bozotic baggage
       | they allow for legacy v4. In particular, your sending IP must
       | have a PTR record and the name in that PTR record must have a
       | AAAA record containing that address.
       | 
       | This is mentioned in the 550 message, but I guess people don't
       | read the logs.
        
         | Filligree wrote:
         | > Gmail has stricter requirements for v6 because they assume if
         | you are using v6 then they can leave aside all the bozotic
         | baggage they allow for legacy v4. In particular, your sending
         | IP must have a PTR record and the name in that PTR record must
         | have a AAAA record containing that address.
         | 
         | This is, in fact, quite difficult to convince your ISP they
         | should do.
        
           | mschuster91 wrote:
           | > This is, in fact, quite difficult to convince your ISP they
           | should do.
           | 
           | For server hosting, I have never seen a provider that doesn't
           | allow me to either set the PTR record or at the very least
           | keep it set to something that resolves back to the IP address
           | in question.
           | 
           | For _residential_ ISPs however the story is different - but
           | who would want to send emails to googlemail from a
           | residential IPv6 address without authenticating themselves?
           | Only spammers would.
        
             | plainolrandy wrote:
             | "Authenticating themselves" to who? This, to me, is just
             | another way of saying "residential users must use an
             | approved sender and can't send mail themselves" since
             | residential users will statistically never be able to get
             | PTRs changed to their domain and instead will have to deal
             | with them pointing to the ISP.
             | 
             | It's another way to force people to use the handful of
             | approved providers to send mail and it's really shitty.
        
               | zinekeller wrote:
               | I'm sure you'll disagree with me but if you're running a
               | computer with an ephemeral address it's very _very_
               | likely that you 're not intending to send mail but
               | instead it's a malicious program unknowingly installed
               | flogging mail, and if you're ISP doesn't provide a static
               | address with PTR chances are that they're also negligent
               | to the point that they're blocked by even the smaller
               | providers simply due to too much spam.
        
               | Avamander wrote:
               | > It's another way to force people to use the handful of
               | approved providers to send mail and it's really shitty.
               | 
               | There are so many and cheap ways to have a matching PTR,
               | so really not really.
               | 
               | The majority of mail from residential ranges is spam and
               | has been for a long time. It's unlikely to change at this
               | point.
        
               | mschuster91 wrote:
               | > It's another way to force people to use the handful of
               | approved providers to send mail and it's really shitty.
               | 
               | You can always go and rent a server somewhere in a random
               | datacenter, the lowest of the low VPS providers are at
               | ~5EUR a month, and send and receive mail from there.
               | Hardly a "handful of providers".
               | 
               | There simply is no alternative to banning sending mail
               | from residential IPs.
        
           | jeffbee wrote:
           | Round-trip DNS consistency is pretty basic and my ISP
           | provides it by default. Note that I didn't say your ISP has
           | to delegate to you, or that your PTR record needs to match
           | your EHLO or anything of that nature.
        
           | vajrabum wrote:
           | Are IPv6 numbers not available from your local registry at
           | low or no cost? Or in these late days must you rent them? Or
           | is this just a problem of people not wanting or knowing how
           | to run BGP so they can control their own fate?
        
             | navaati wrote:
             | Run BGP... with whom ? Let's say I have my own AS and a
             | prefix given to me, which is indeed quite open and not too
             | costly. If my ISP coming to my facility won't allow me to
             | set a PTR record, they for sure won't allow me to run BGP
             | session with them !
        
               | icedchai wrote:
               | There are VPS providers out there (like Vultr) that offer
               | BGP. You can either use the IPs on their cloud instances,
               | or tunnel IPs back to your home network, etc.
        
               | gunapologist99 wrote:
               | Vultr is actually really awesome. (And highly unusual in
               | their BGP support!)
        
             | nybble41 wrote:
             | You're supposed to get your IPv6 prefix from your ISP's
             | allocation, not directly from the regional registry.
             | Simplifying the routing tables with hierarchical address
             | assignment was one of the major selling points for the
             | larger address size in IPv6. If everyone gets their own
             | prefix independent from their ISP then the core Internet
             | routing tables will continue to grow ever more complicated.
        
         | jeroenhd wrote:
         | The 550 messages are quite clear, but Gmail has the nasty
         | tendency to accept email and then flag it as spam, stuffing it
         | away in the spam folder to be automatically deleted in 30 days.
         | 
         | Requiring SPF/DMARC/DKIM/PTR shouldn't really be a problem, but
         | there are extra layers of spam filtering on top of the problems
         | Gmail will give you feedback about.
        
           | Avamander wrote:
           | > Requiring SPF/DMARC/DKIM/PTR shouldn't really be a problem
           | 
           | Oh I wish that were the case. One recent "lovely" example I
           | stubled upon is Deutche Telekom (t-online.de) not willing to
           | use SPF because it's not perfect enough for them.
           | 
           | It's only the tip of the iceberg unfortunately.
        
       | hdjjhhvvhga wrote:
       | I remember that was the first thing I used to do on my mail
       | servers, ever before DKIM etc. Why? I have no idea and I will
       | never know. Is sending email via IPv6 important to me? No. Is
       | mail delivery important to me? Yes. Why is Google such a bad
       | player in this field? Because in spite of having the biggest
       | email network they don't want to allocate relevant resources to
       | handle spammers properly. In other words, they are OK with false
       | negatives, that is us. For this reason, I'm fine with this ugly
       | workaround.
        
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       (page generated 2022-06-03 23:01 UTC)