95resume: Do not resume on iSCSI

[danimo]

The iSCSI configuration is started after dracut checks for resume,
so we run into a timeout here. Additionally it's questionable if
resume on iSCSI makes sense (or is even supported on the platform),
so disable it for now.

References: bsc#999663

Signed-off-by: Hannes Reinecke hare@suse.com

[centos-ci]

Can one of the admins verify this patch?

[danimo]

@centos-ci ok to test

[danimo]

@haraldh Can you give me the magic power to trigger CI runs?

[haraldh]

@danimo you now have the power :) May the force be with you :)

[haraldh]

@centos-ci ok to test

[haraldh]

What, if the swap partition is local?

[danimo]

Back from vacation.

Fair point. Is there a reliable way to tell if all swap storage is truly local?

[haraldh]

Wouldn't it be better to just tell the user not to place resume=<path to iSCSI partition> on the kernel command line?

[haraldh]

Ah, Suse is compiling that in the initramfs. So the resume dracut module should skip network block devices.

[danimo]

Does dracut already have a function to drill down && check for the type of the underlying block device?

[haraldh]

Nothing globally yet.

modules.d/95iscsi/module-setup.sh has for example:

    is_iscsi() {
        local _dev=$1

        [[ -L "/sys/dev/block/$_dev" ]] || return
        cd "$(readlink -f "/sys/dev/block/$_dev")"
        until [[ -d sys || -d iscsi_session ]]; do
            cd ..
        done
        [[ -d iscsi_session ]]
    }

modules.d/95nbd/module-setup.sh has:

   is_nbd() { [[ -b /dev/block/$1 && $1 == 43:* ]] ;}

[danimo]

Any suggestion on how to avoid code dupes? {iscsi,nbd}-lib.sh will not work, as they cannot be sourced from the module-setup.sh that installs them.

[haraldh]

well, put those functions in dracut-functions.sh, create a function block_is_netdevice(), which calls all tests for network devices and use that.

[haraldh]

will you or should I?

[dustymabe]

this looks related to #480 - can someone confirm?

[haraldh]

@danimo ping

[haraldh]

please rebase

[danimo]

Done. But the swap_on_netdevice check should probably also be hostonly, right?

[haraldh]

Done. But the swap_on_netdevice check should probably also be hostonly, right?

correct

[danimo]

Done.

[Conan-Kudo]

@danimo It looks good, but can you rebase on current master?

[danimo]

@Conan-Kudo done.