[HN Gopher] Diskomator - NVMe-TCP at your fingertips
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       Diskomator - NVMe-TCP at your fingertips
        
       Author : simjue
       Score  : 46 points
       Date   : 2023-11-15 18:35 UTC (4 hours ago)
        
 (HTM) web link (github.com)
 (TXT) w3m dump (github.com)
        
       | anotherhue wrote:
       | >I'd like to live to see a future where people build appliances
       | like this for various purposes, not just this specific NVMe one.
       | For example, a nice thing to have would be an appliance whose
       | only job is to make all local displays available via Miracast. I
       | hope this repository is inspiration enough for an interested
       | soul, to get this off the ground.
       | 
       | Very nice idea.
        
       | mike_d wrote:
       | I seem to recall an announcement from Western Digital(?) years
       | ago about a line of hard drives with a direct ethernet interface.
       | Does anyone remember the same or what might have come of it?
       | 
       | The market is saturated with solutions for middle-boxes that make
       | hard drives talk to networks, but nobody seems to be directly
       | addressing the problem of we just want storage network
       | accessible.
        
         | _zoltan_ wrote:
         | Kioxia has a line of products (EM6) that has an embedded
         | Marvell NVMeoF/{TCP,RDMA} controller and Foxconn has a chassis
         | that can take them and expose them just directly on the
         | network. neat stuff.
        
           | gorkish wrote:
           | Neat if you can stomach paying for the novelty. Let's see an
           | open product that does the same for any old M.2 stick
        
             | _zoltan_ wrote:
             | SPDK + RDMA works just fine :)
        
               | gorkish wrote:
               | Yeah i know the software exists; it's finding ways to
               | actually build systems from it that sucks. 2.5 gigabit
               | ethernet has absolutely killed dead all momentum for
               | getting faster interfaces in consumer hardware and SBCs
               | unfortunately. I don't want to build a 2-drive OSD using
               | a comparatively gargantuan microATX motherboard.
        
         | toast0 wrote:
         | > The market is saturated with solutions for middle-boxes that
         | make hard drives talk to networks, but nobody seems to be
         | directly addressing the problem of we just want storage network
         | accessible.
         | 
         | Most hard drives run a serial console on some of the jumpers.
         | You can easily run PPP or SLIP over that. QED :P
        
           | ronsor wrote:
           | Nothing like those blazing fast 115kbps read/write speeds.
        
           | csdvrx wrote:
           | Tell me more, like a brand and model where I can do that!
           | 
           | BTW if you already explored that, would you know how to alter
           | the SLC/MLC ratio by any chance?
           | 
           | Modern QLC drive often have a SLC area for buffering. With
           | the right firmware tools, it should be possible to take a 4
           | TB QLC drive and convert it to a 1 SLC drive to get more
           | performance.
        
             | EvanAnderson wrote:
             | An older reference for hacking hard disk drives:
             | https://spritesmods.com/?art=hddhack
             | 
             | There were some firmware bugs on Seagate Barracuda SATA
             | drives that could be worked-around w/ serial console. I
             | don't remember the specifics though.
             | 
             | If you some search-engining on hard drive manufacturers and
             | "serial console" you'll find indexed pages. (Presumably the
             | really interesting stuff is buried deep down in forum
             | posts, etc.) Just doing a couple quick searches got me some
             | stuff.
        
         | gorkish wrote:
         | > The market is saturated with solutions for middle-boxes that
         | make hard drives talk to networks
         | 
         | It's my experience that these boxes try to do a hell of a lot
         | more than just putting drives-on-network and that is why they
         | all suck and are expensive.
         | 
         | The NVMe-oF fabric devices out there all seem to command a
         | ridiculous premium when the reality is they ought to be very
         | simple and easily cost-optimized.
        
         | matja wrote:
         | There was a line of products called EtherDrive made by Coraid
         | in the early 2000's that was basically a SATA to ATAoE bridge
         | on the most basic devices, up to rack-mount solutions that used
         | a Linux OS and Dell HBA to run vblade
         | (https://github.com/OpenAoE/vblade) to expose a Linux MD array
         | carved up using LVM2.
         | 
         | ATAoE ("aoe" in the Linux kernel) is nice because it is very
         | lightweight in both terms of code to implement it (~2-3kloc,
         | basically just stuff an ATA packet in an ethernet frame), low
         | network overhead, and ease to setup (no IP addresses).
        
         | wkennington wrote:
         | Seagate kinetic
         | 
         | https://www.seagate.com/files/www-content/product-content/hd...
        
         | wmf wrote:
         | I don't think the economics of this work because an Ethernet
         | network is probably much more expensive than SAS and network
         | configuration is more complex (you could make it zeroconf but
         | that's also zero security).
        
         | justsomehnguy wrote:
         | > Does anyone remember the same or what might have come of it?
         | 
         | Nothing, because it makes each disk quite costly and by the
         | 2014 nobody wanted costly _and slow_ HDDs.
         | 
         | Check the Seagate offering up there it has 1Gbit interface. You
         | can't even run the drive at full sequential read/write speed
         | over it. And having a two 10Gbit ports on each drive would
         | require having two 10Gbit switches, which by 2014 were still
         | quite costly.
         | 
         | EM6 solution[0,1] is neat but at least it both the quite packed
         | both by the spec and the price but delivers a lot of IOPS and
         | throughput.
         | 
         | [0]
         | https://www.ingrasys.com/assets/files/Datasheet_ES2000_20211...
         | [1] https://www.servethehome.com/ethernet-ssds-hands-on-with-
         | the...
        
       | withinboredom wrote:
       | I'm looking forward to Longhorn[1] taking advantage of this
       | technology.
       | 
       | [1]: https://github.com/longhorn/longhorn
        
       | EnigmaCurry wrote:
       | How does this compare with iSCSI?
        
         | withinboredom wrote:
         | Like an iops improvement of 30%+ and latency improvement of
         | 20%+[1], ish.
         | 
         | [1]:
         | https://www.reddit.com/r/Proxmox/comments/134kqy3/iscsi_and_...
        
       | gorkish wrote:
       | This is awesome. Would be exciting if it can be extended to
       | support NVMe-oF as well with RDMA via RoCEv2. A SBC running
       | something like this with at least 2x10GbE and two M.2 slots and 2
       | sata ports would be an absolute dream device for me.
        
       | EvanAnderson wrote:
       | I never really used Mac machines, but I always appreciated
       | "target disk mode". This sounds similar, albeit over a network
       | (which could simply be a straight-thru cable between Ethernet
       | NICs on two machines).
       | 
       | Edit: Yeah. I forgot about actually saying what "target disk mode
       | was". There's a child post that mentions it, so I'll refrain. I
       | will say that I saw it used in imaging computers in a college
       | computer lab setting back in the early 2000's. I definitely
       | wished my PCs could've done it. It looked like a very handy
       | feature. Presumably it would make fixing OS boot issues easier,
       | as well as just harvesting files off a machine that was otherwise
       | not operating properly due to OS issues.
        
         | metadat wrote:
         | Diskomater appears to be an open source, platform agnostic
         | version of this underlying technology!
         | 
         | In case, like me, "Target Disk Mode" is not something you're
         | familiar with:
         | 
         | > People also ask What is the target disk mode? If you have two
         | Mac computers with USB, USB-C or Thunderbolt ports, you can
         | connect them so that one of them appears as an external hard
         | disk on the other. This is called target disk mode. Note: If
         | either of the computers has macOS 11 or later installed, you
         | must connect the two computers using a Thunderbolt cable.
         | 
         | Sidenote: Thunderbolt cables are special USB-C cables, i.e. the
         | wire between your Mac and the USB-C power brick.
        
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       (page generated 2023-11-15 23:00 UTC)