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6 commits

Author SHA1 Message Date
Maximilian Bosch 4682e40183 ssh-ng: better way to keep SSH errors visible
A better fix than in 104448e75d, hence a
revert + the fix.

It turns out that this commit has the side-effect that when having e.g.
`StrictHostKeyChecking=accept-new` for a remote builder, the warnings à la

    Warning: Permanently added 'builder' (ED25519) to the list of known hosts.

actually end up in the derivation's log whereas hostkey verification
errors don't, but only in the stderr of the `nix-build` invocation
(which was the motivation for the patch).

This change writes the stderr from the build-hook to

* the daemon's stderr, so that the SSH errors appear in the journal
  (which was the case before 104448e75d)
* the client's stderr, as a log message
* NOT to the drv log (this is handled via `handleJSONLogMessage`)

I tried to fix the issue for legacy-ssh as well, but failed and
ultimately decided to not bother.

I know that we'll sooner or later replace the entire component, however
this is the part of the patch I have working for a while, so I figured I
might still submit it for the time being.

Change-Id: I21ca1aa0d8ae281d2eacddf26e0aa825272707e5
2024-10-14 06:01:18 +00:00
Maximilian Bosch 104448e75d ssh-ng: Set log-fd for ssh to 4 by default
That's expected by `build-remote` and makes sure that errors are
correctly forwarded to the user. For instance, let's say that the
host-key of `example.org` is unknown and

    nix-build ../nixpkgs -A hello -j0 --builders 'ssh-ng://example.org'

is issued, then you get the following output:

    cannot build on 'ssh-ng://example.org?&': error: failed to start SSH connection to 'example.org'
    Failed to find a machine for remote build!
    derivation: yh46gakxq3kchrbihwxvpn5bmadcw90b-hello-2.12.1.drv
    required (system, features): (x86_64-linux, [])
    2 available machines:
    [...]

The relevant information (`Host key verification failed`) ends up in the
daemon's log, but that's not very obvious considering that the daemon
isn't very chatty normally.

This can be fixed - the same way as its done for legacy-ssh - by passing
fd 4 to the SSH wrapper. Now you'd get the following error:

    cannot build on 'ssh-ng://example.org': error: failed to start SSH connection to 'example.org': Host key verification failed.
    Failed to find a machine for remote build!
    [...]

...and now it's clear what's wrong.

Please note that this is won't end up in the derivation's log.

For previous discussion about this change see
https://github.com/NixOS/nix/pull/7659.

Change-Id: I5790856dbf58e53ea3e63238b015ea06c347cf92
2024-04-26 19:04:06 +02:00
eldritch horrors 34fb7a7e9d make the multi-node vm tests a bit more reliable
without these changes the tests will very repeatably (although not very
reliably) wedge in our runs. the ssh command starts, opens a sessions,
does something, the session closes again, but the test does not move on.
adding *just* the redirect and not the unit waits is not sufficient
either, it needs both. this feels like a bug in the nixos testing
framework somewhere, but digging that far is not in the cards right now.

Change-Id: Idab577b83a36cc4899bb5ffbb3d9adc04e83e51c
2024-03-10 10:10:52 +01:00
eldritch horrors f10e673272 tests/nixos/remote-builds*: Inline module + format
(cherry picked from commit 5167351efbee5c5a7390510eb720c31c6976f4d9)
Change-Id: I0caba23b589ed428d08895d7b8f0c22532bd259e
2024-03-06 21:32:47 -07:00
eldritch horrors 097acae35b tests/nixos: Test remote build against older versions
(cherry picked from commit e502d1cf945fb3cdd0ca1e1c16ec330ccab51c7b)
Change-Id: If6a1758b6457c5dae9305829c4d71d1905cfca22
2024-03-06 21:32:47 -07:00
eldritch horrors 706f0df55b Merge pull request #9280 from R-VdP/rvdp/fix_remote_logging_phase_reporting
Include phase reporting in log file for ssh-ng builds

(cherry picked from commit b1e7d7cad625095656fff05ac4aedeb12135110a)
Change-Id: I4076669b0ba160412f7c628ca9113f9abbc8c303
2024-03-06 19:11:12 -07:00