Multipath curthook can't be disabled

[Matthew Steele]

Taken from detect_and_handle_multipath in

/snap/subiquity/5097/lib/python3.10/site-packages/curtin/commands/curthooks.py:

-------

def detect_and_handle_multipath(cfg, target, osfamily=DISTROS.debian):
    DEFAULT_MULTIPATH_PACKAGES = {
        DISTROS.debian: ['multipath-tools-boot'],
        DISTROS.redhat: ['device-mapper-multipath'],
        DISTROS.suse: ['multipath-tools'],
    }
    if osfamily not in DEFAULT_MULTIPATH_PACKAGES:
        raise ValueError(
                'No multipath package mapping for distro: %s' % osfamily)

    mpcfg = cfg.get('multipath', {})
    mpmode = mpcfg.get('mode', 'auto') <-------------I
    mppkgs = mpcfg.get('packages',
                       DEFAULT_MULTIPATH_PACKAGES.get(osfamily))
    mpbindings = mpcfg.get('overwrite_bindings', True)

    if isinstance(mppkgs, str):
        mppkgs = [mppkgs]

    if mpmode == 'disabled': <--------------
        return

    mp_device = block.detect_multipath(target)
    LOG.info('Multipath detection found: %s', mp_device)
    if mpmode == 'auto' and not mp_device:
        return

--------

As I read this, it means that the hook will terminate if the value of multipath/mode is 'disabled', and will assign that value to 'auto' if the setting isn't detected.

Multipath appears as a top-level config key in the Curtin documentation, but I am not able to get it to be read into /var/log/installer/curtin-install/subiquity-curthooks.conf (where I assume it is being loaded), no matter where I put it in my user-data file.

Is it intended to be able to disable multipath in this fashion for autoinstall?

[Michael Hudson-Doyle (mwhudson)]

It has generally not been a goal so far to allow customization of all aspects of the curtin config subiquity creates. Perhaps there should be...

[Matthew Steele (msteele68)]

If the hook was a curtin addition or just future-proofing, that would be understandable. I just wanted to make sure that I wasn't missing the way to do it.