** Description changed: + [ Impact ] + + Users running `do-release-upgrade` in a LXD VM through `lxc exec` have + their session disconnected abruptly as lxd-agent.service is restarted + during the upgrade from Jammy->Noble. + + The disconnected user will likely re-enter the VM using another `lxc + exec` but might be confused by the `do-release-upgrade` command still + running but being hard to re-attach. + + The upload would fix this disconnect problem by simply not stopping the + `lxd-agent.service` on package upgrade. + + [ Test Plan ] + + How to reproduce the bug: + + ``` + lxc launch ubuntu:jammy jammy-to-noble --vm + lxc shell jammy-to-noble + # now inside the VM + do-release-upgrade + + [snipped] + Setting up libkeyutils1:amd64 (1.6.3-3build1) ... + Setting up lxd-agent-loader (0.7) ... + Error: websocket: close 1006 (abnormal closure): unexpected EOF + ``` + + With a fixed lxd-agent-loader package, there should be no abnormal closure of the websocket connection. + The `do-release-upgrade` should be able to complete without any session disconnection. + + [ Where problems could occur ] + + The fix for this upgrade is to not restart the `lxd-agent.service` on + package upgrade. This means subsequent fixes delivered through package + updates would not be picked up immediatly. In those case, a VM restarted + would be required. + + This scenario is mitigated by the fact that `lxd-agent.service` already has a `Restart=on-failure` directive meaning that if something changes on the LXD side causing it to crash, an updated lxd-agent binary would be picked up after the first crash. + Another mitigating factor is that LXD VMs don't require the `lxd-agent.service` to be working to trigger an orderly shutdown as ACPI signals are sent in the QEMU process. + + [ Original description ] + If `do-release-upgrade` is run in LXD VM using `lxc exec <instance> bash` or `lxc shell <instance>` to run the upgrade command, the upgrade process will restart lxd-agent.service during an upgrade from Jammy to Noble, thus causing the `lxc exec` session to be disconnected abruptly. Simple reproducer steps: ``` lxc launch ubuntu:jammy jammy-to-noble --vm lxc shell jammy-to-noble # now inside the VM do-release-upgrade [snipped] Setting up libkeyutils1:amd64 (1.6.3-3build1) ... Setting up lxd-agent-loader (0.7) ... Error: websocket: close 1006 (abnormal closure): unexpected EOF ``` Reported to LXD upstream in https://github.com/canonical/lxd/issues/14033
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2078936 Title: lxd-agent restarts during do-release-upgrade breaking the `lxc exec` connection To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lxd-agent-loader/+bug/2078936/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
