Hi all. I’m trying to install maas via snap on LXD per the docs:
When installing on LXD with Ubuntu 20.04, I receive the following error:
$ sudo snap install maas error: cannot perform the following tasks: - Run install hook of "maas" snap if present (run hook "install": chown: changing ownership of '/var/snap/maas/common/log': Invalid argument)
I’ve tried several things to resolve this, with the same error each time, such as:
- Trying to install the snap as root, or as a regular user (with sudo)
- Trying with different security confinement/mode (like --devmode)
I do see one user reported the same error here for an arm64 snap install whereas I am testing on x86_64 Linux (LXD on NixOS):
To try and debug, if I download the snap, unsquash it, comment out the one bash line in the install hook script which is throwing the error, it then seems to complete the install successfully (although I have no idea if it will actually work properly – haven’t tested that far yet):
$ snap download maas Fetching snap "maas" Fetching assertions for "maas" Install the snap with: snap ack maas_8980.assert snap install maas_8980.snap $ sudo unsquashfs maas_8980.snap Parallel unsquashfs: Using 12 processors 26365 inodes (27330 blocks) to write created 23305 files created 6747 directories created 2851 symlinks created 0 devices created 0 fifos # Comment out the failing `chown` command on line 31 of the `snap/hooks/install` script: # # 29 if [ ! -d "$SNAP_COMMON/log" ]; then # 30 mkdir -m 775 "$SNAP_COMMON/log" # 31 chown snap_daemon "$SNAP_COMMON/log" # 32 fi # $ sudo sed -i 's|chown snap_daemon "$SNAP_COMMON/log"|# chown snap_daemon "$SNAP_COMMON/log"|g' squashfs-root/snap/hooks/install $ sudo snap try squashfs-root/ maas 2.8.2-8577-g.a3e674063 mounted from /home/maasuser/test/squashfs-root $ snap list Name Version Rev Tracking Publisher Notes core18 20200929 1932 latest/stable canonical✓ base lxd 4.0.3 16922 4.0/stable/… canonical✓ - maas 2.8.2-8577-g.a3e674063 x2 - - try maas-cli 0.6.5 13 latest/stable canonical✓ - ripgrep 12.1.0 9 latest/stable icey classic snapd 2.47.1 9721 latest/stable canonical✓ snapd
chown command fails on:
chown snap_daemon $FILE
The snap_daemon user is uid 584788, and the lxc container appears to only recognize UIDs to 65535 by default.
How can I get the container to allow the snap_daemon UID of 584788 to be allowed? In my case, snap exists inside the container only as the host OS is NixOS without snap.
chown snap_daemon $FILE, an “Invalid argument” error is thrown for any UIDs larger than 65535:
fchownat(AT_FDCWD, "test", 584788, -1, 0) = -1 EINVAL (Invalid argument)
It looks like maybe I can solve this by expanding the uid Maprange to allow uid 584788 with something like: “security.idmap.size”, but so far no luck:
Error: Failed to get ID map: Not enough uid/gid available for the container
Anyone have any ideas on why this error is happening and how to resolve it other than the script hack to comment the offending chown line out above?