bug#73306: guix deploy fails with dropbear ssh server

[Attila Lendvai <attila@lendvai.name>]

should `guix deploy` work with dropbear?

on one of my servers i have replaced openssh with dropbear.

(service dropbear-service-type
         (dropbear-configuration
          (port-number 22)
          (password-authentication? #false)
          ;; To allow `guix deploy` to connect as root.
          (root-login? #true)))

i `guix deploy`ed the config, even rebooted the machine. all works fine, except when i want to `guix deploy` once again:

$ guix deploy x.scm
The following 1 machine will be deployed:
  lendvai

guix deploy: deploying to lendvai...
;;; [2024/09/16 23:10:53.550882, 0] [GSSH ERROR] : #<input-output: channel (closed by the remote side) 7fccff89d080>
Backtrace:
In ice-9/boot-9.scm:
  1752:10 19 (with-exception-handler _ _ #:unwind? _ #:unwind-for-type _)
In guix/status.scm:
    839:4 18 (call-with-status-report _ _)
In ice-9/boot-9.scm:
  1752:10 17 (with-exception-handler _ _ #:unwind? _ #:unwind-for-type _)
In guix/store.scm:
   689:37 16 (thunk)
   1330:8 15 (call-with-build-handler #<procedure 7fccf6b996c0 at guix/ui.scm:1240:2 (continue store things mode)> _)
In guix/scripts/deploy.scm:
   284:23 14 (_)
In guix/store.scm:
  1412:11 13 (map/accumulate-builds #<store-connection 256.100 7fccf0dc30a0> #<procedure 7fccff88e540 at guix/scripts/deploy.scm:285:45 (t-1e3fba6565d6004…> …)
   1330:8 12 (call-with-build-handler #<procedure 7fccf6ba0b10 at guix/store.scm:1365:2 (continue store things mode)> _)
In ice-9/boot-9.scm:
  1752:10 11 (with-exception-handler _ _ #:unwind? _ #:unwind-for-type _)
In guix/scripts/deploy.scm:
   166:29 10 (_)
In gnu/machine/ssh.scm:
   513:25  9 (deploy-managed-host #<<machine> operating-system: #<<operating-system> kernel: #<package linux-libre@6.10.9 gnu/packages/linux.scm:974 7fccf4…>)
    397:2  8 (check-deployment-sanity #<<machine> operating-system: #<<operating-system> kernel: #<package linux-libre@6.10.9 gnu/packages/linux.scm:974 7f…>)
   365:17  7 (machine-check-building-for-appropriate-system _)
In guix/ssh.scm:
   204:18  6 (remote-system _)
   191:15  5 (remote-inferior _ _)
In ssh/popen.scm:
     64:4  4 (open-remote-pipe* #<session root@lendvai.name:22 (connected) 7fccfd6fafe0> "r+" _ . _)
In unknown file:
           3 (channel-open-session #<input-output: channel (closed by the remote side) 7fccff89d080>)
In ice-9/boot-9.scm:
  1685:16  2 (raise-exception _ #:continuable? _)
  1685:16  1 (raise-exception _ #:continuable? _)
  1685:16  0 (raise-exception _ #:continuable? _)

ice-9/boot-9.scm:1685:16: In procedure raise-exception:
Throw to key `guile-ssh-error' with args `("channel-open-session" "" #<input-output: channel (closed by the remote side) 7fccff89d080> #f)'.



the ssh login part seems to have worked fine according to /var/log/secure:

Sep 16 23:10:52 localhost dropbear[489]: Pubkey auth succeeded for 'root' with ssh-ed25519 key SHA256:[...] from [...]
Sep 16 23:10:53 localhost dropbear[489]: Exit (root) from <...>: Exited normally

-- 
• attila lendvai
• PGP: 963F 5D5F 45C7 DFCD 0A39
--
“Let him who would move the world, first move himself.”
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