Storage configuration in rootless mode varies based on whether CONTAINERS_STORAGE_CONF is set.

[nm004]

A normal user can change the storage configuration, namely, graphroot, rootless_storage_path and runroot via storage.conf in rootless mode, but the result is different based on whether $CONTAINERS_STORAGE_CONF is set or not, even when $CONTAINERS_STORAGE_CONF = $XDG_CONFIG_HOME/containers/storage.conf.

I tested two cases and the results are the following.

When unset $CONTAINERS_STORAGE_CONF ($XDG_CONFIG_HOME/containers/storage.conf exists):

• graphroot: used
• rootless_storage_path: used only when graphroot not set
• runroot: used

When set $CONTAINERS_STORAGE_CONF:

• graphroot: not used
• rootless_storage_path: used
• runroot: not used

In my opinion, both graphroot and runroot are should be used regardless whether $CONTAINERS_STORAGE_CONF is set or not (always prefer the first result).

Related issues

#18375
containers/storage#1469
containers/storage#1587