Cannot communicate with server: Post "http://localhost/v2/snaps/snapcraft"

snapcraft
1

I’m trying to make a new build of my snap “maven-central-search” as I got notified it contains outdated packages.

For almost three weeks now, I consistently get the following error at the end of the build log:

Setting up snapd (2.61.4ubuntu0.16.04.1+esm1) ...
Setting up dh-python (2.20151103ubuntu1.2) ...
Processing triggers for libc-bin (2.23-0ubuntu11.3+esm9) ...
Processing triggers for systemd (229-4ubuntu21.31+esm3) ...
Restarting host AppArmor
Command output: b''
Command errors (if any): b''
error: cannot communicate with server: Post "http://localhost/v2/snaps/snapcraft": dial unix /run/snapd.socket: connect: no such file or directory
Install failed
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/lpbuildd/target/build_snap.py", line 319, in run
    self.install()
  File "/usr/lib/python3/dist-packages/lpbuildd/target/build_snap.py", line 181, in install
    self.backend.run(
  File "/usr/lib/python3/dist-packages/lpbuildd/target/lxd.py", line 735, in run
    subprocess.check_call(cmd, **kwargs)
  File "/usr/lib/python3.12/subprocess.py", line 413, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['lxc', 'exec', 'lp-xenial-amd64', '--', 'linux64', 'snap', 'install', '--classic', '--channel=4.x/stable', 'snapcraft']' returned non-zero exit status 1.
Revoking proxy token...
[Wed Mar  4 10:10:32 2026]
RUN: /usr/share/launchpad-buildd/bin/in-target scan-for-processes --backend=lxd --series=xenial --abi-tag=amd64 --isa-tag=amd64 SNAPBUILD-3076248
Scanning for processes to kill in build SNAPBUILD-3076248

My code is on GitHub and I use SnapCraft Builds to create the snaps. Any idea how to resolve this?

2

It looks like the snapd isn’t running on the build host for some reason.

3

The build host is part of snapcraft.io, so I can’t really influence that.

4

The store build infrastructure also runs the build in the Launchpad build farm, so pinging the Launchpad guys may help(IIRC they have a Launchpad Answers page or something).