[HN Gopher] Using rsync to create a limited ability to write rem...
___________________________________________________________________
Using rsync to create a limited ability to write remote files
Author : zdw
Score : 34 points
Date : 2024-09-05 04:48 UTC (3 days ago)
(HTM) web link (utcc.utoronto.ca)
(TXT) w3m dump (utcc.utoronto.ca)
| evilDagmar wrote:
| Absolutely. I have used the heck out of this on systems since I
| found out about rrsync.pl and read through the code to make sure
| it was using a solid approach.
|
| With a quick keypair generation one can quickly deploy read-only
| (and probably write-only although I've never tried that) access
| to select parts of a filesystem and do selective near-line
| backups of important files into a "history" host of sorts, and
| even leverage rsync's ability to use hardlinks in place of files
| that have not changed since the last run so no space is
| needlessly wasted backing up 400 copies of the same thing.
|
| It was wonderful that I didn't have to write such a wrapper
| myself.
| therein wrote:
| Didn't know this existed, useful to know for sure.
|
| I am guessing one would want to disable the Sftp subsystem for
| SSH too.
| rsync wrote:
| There is a mistake that some people make when pointing simple
| rsync jobs to us - they preserve ownership but send files owned
| by root.
|
| This actually works... They successfully back up their files to
| their account with 0:0 ownership.
|
| But, of course, they are not root on our end so they either lose
| the ability to write or change the files... Or they lose the
| ability to read them at all.
|
| The easy solution is this neat rsync argument --fake-super ...
| but I guess _you could make this mistake on purpose_ with
| permissions that allowed read access to all ... and successfully
| create write once, read, only backups...
| jraph wrote:
| > But, of course, they are not root on our end
|
| Could this be made possible using something like user
| namespaces / containers with their own hostnames?
| Denvercoder9 wrote:
| Instead of writing out "no-port-forwarding,no-X11-forwarding,no-
| agent-forwarding,no-pty" in the authorized_keys file; you can use
| the "restrict" keyword to enable all current and future
| restrictions.
___________________________________________________________________
(page generated 2024-09-08 23:01 UTC)