Re: [PATCH pve-cluster 8/9] fix #7294: cluster: helpers: add cluster-wide version assertion

["Daniel Kral" <d.kral@proxmox.com>]

On Thu Jun 11, 2026 at 4:59 PM CEST, David Riley wrote:
> Add function to assert a minimum version requirement for the whole
> cluster.
>
> Evaluates against the cluster configuration. Dies if any node is
> offline, or running an older version, ensuring cluster-wide feature
> compatibility before allowing an operation to proceed.
>
> Prevents older nodes from truncating newly structured user.cfg
> entries.
>
> Link: https://bugzilla.proxmox.com/show_bug.cgi?id=7294
> Signed-off-by: David Riley <d.riley@proxmox.com>
> ---
>  src/PVE/Cluster/Helpers.pm | 35 +++++++++++++++++++++++++++++++++++
>  1 file changed, 35 insertions(+)

As for the previous patch, this could go in PVE::Cluster as code that
already depends on some cluster-related functionality has it imported,
but no hard feelings about this.

>
> diff --git a/src/PVE/Cluster/Helpers.pm b/src/PVE/Cluster/Helpers.pm
> index a4b41c9..3937e6d 100644
> --- a/src/PVE/Cluster/Helpers.pm
> +++ b/src/PVE/Cluster/Helpers.pm
> @@ -47,5 +47,40 @@ sub version_cmp {
>      return 0;
>  }
>  
> +# Asserts that all configured nodes in the cluster meet a minimum version requirement.
> +# Evaluates against the full, static cluster node list rather than only live nodes.
> +# Aborts if any node is offline, unreadable, or running an
> +# outdated version, preventing partial feature rollouts from corrupting cluster state.
> +sub assert_min_cluster_version {
> +    my ($major, $minor, $release) = @_;
> +
> +    my $nodestat = PVE::Cluster::get_node_kv('version-info') || {};
> +
> +    my $clinfo = PVE::Cluster::get_clinfo() || {};
> +    my $nodelist = $clinfo->{nodelist} || {};

This might be unnecessary for single-node setups as there we can enforce
versioned dependencies much more easily through package version
constraints, but it should be noted that the $nodelist hash will be
empty if no cluster has been created.

If we want to make this assertion also work on single-node setups, this
could use PVE::Cluster::get_nodelist(), which fakes the nodelist for a
single node.

Either way, that should probably go in the subroutine's description.

> +
> +    foreach my $node (sort keys %$nodelist) {

nit: for new code we use 'for' in favor of 'foreach' [0]

[0] https://pve.proxmox.com/wiki/Perl_Style_Guide#Perl_syntax_choices

> +        my $raw_json = $nodestat->{$node};
> +
> +        if (!defined($raw_json)) {
> +            die "cannot execute operation: cluster node '$node' is offline or not reporting its"
> +                . " version. All nodes must be online to verify cluster-wide feature support.\n";
> +        }
> +
> +        my $vinfo = eval { decode_json($raw_json) };
> +        if ($@ || !$vinfo || !$vinfo->{version}) {
> +            die "cannot execute operation: failed to parse cluster version string for node"
> +                . " '$node'.\n";
> +        }
> +
> +        if (!pvecfg_min_version($vinfo->{version}, $major, $minor, $release)) {
> +            die "cannot execute operation: cluster node '$node' runs an older version of Proxmox"
> +                . " VE ($vinfo->{version}) than the required $major.$minor.$release. Please"
> +                . " upgrade all nodes first.\n";
> +        }
> +    }
> +    return 1;
> +}
> +
>  1;
>