Re: [PATCH container v9 06/10] add linked clone check when destroying container template

[Fiona Ebner <f.ebner@proxmox.com>]

Am 29.06.26 um 4:04 PM schrieb Michael Köppl:
> This check matches the behavior already implemented for VMs and prevents
> partial storage deletion if a container template has a linked clone. In
> such cases, the destruction of the container template will now fail,
> informing the user that the base volume is still in use by the linked
> clone. In case of a storage error (such as the underlying storage no
> existing anymore), a warning will be printed and execution continues,
> mimicking the handling of storage errors in later stages of
> destroy_lxc_container().
> 
> Originally-by: Stefan Hrdlicka <s.hrdlicka@proxmox.com>
>  [ MK: use classify_mountpoint instead of pattern matching
>        display warning for storage errors during linked clone check
>        resolve style nit ]
> Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
> ---
>  src/PVE/LXC.pm | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/src/PVE/LXC.pm b/src/PVE/LXC.pm
> index e76da29f..c9f3cba7 100644
> --- a/src/PVE/LXC.pm
> +++ b/src/PVE/LXC.pm
> @@ -1024,6 +1024,25 @@ sub destroy_lxc_container {
>      my ($storage_cfg, $vmid, $conf, $replacement_conf, $purge_unreferenced) = @_;
>  
>      my $volids = {};
> +
> +    if ($conf->{template}) {
> +        PVE::LXC::Config->foreach_volume_full(
> +            $conf,
> +            { include_unused => 1 },
> +            sub {
> +                my ($ms, $mountpoint) = @_;
> +                my $volid = $mountpoint->{volume};
> +                return if !$volid || PVE::LXC::Config->classify_mountpoint($volid) ne 'volume';
> +                my $result =
> +                    eval { PVE::Storage::volume_is_base_and_used($storage_cfg, $volid) };
> +                PVE::RESTEnvironment::log_warn(
> +                    "failed to check if volume '$volid' is used by linked clones: $@")
> +                    if $@;

Style nit: multi-line post-if. If you import the log_warn() directly, it
should be shorter ;)

Maybe note with a comment that this is an early check and removal of the
volume itself would still fail later, which is why it's fine to just log
a warning here.

> +                die "base volume '$volid' is still in use by linked clone\n" if $result;
> +            },
> +        );
> +    }
> +
>      my $remove_volume = sub {
>          my ($ms, $mountpoint) = @_;
>