[PATCH cluster/manager 0/2] fix #6501: allow cluster names up to 32 characters

[Kefu Chai <k.chai@proxmox.com>]

The cluster name is limited to 15 characters. The limit dates back to
2011, when clusters ran on cman. corosync 3, corosync-qdevice and
pmxcfs handle longer names, so this series raises the limit to 32, in
the cluster create API (pve-cluster) and in the create dialog
(pve-manager). The allowed characters stay the same.

On master and on stable-bookworm (pve-cluster 8.1), the name is only
checked when a cluster is created. Joining a node copies corosync.conf
as is, and parse_conf, pmxcfs and qnetd don't limit the name. So older
nodes, including ones that join later, should work with a longer name,
and so should a downgrade. The reporter also says a longer name set in
corosync.conf by hand works for them.

On a single node, the two packages can be upgraded in either order:

- new pve-cluster, old pve-manager: the GUI still stops at 15, while
  pvecm and the API take 32
- old pve-cluster, new pve-manager: the GUI takes 32, but the API
  rejects anything over 15 ("value may only be 15 characters long")
  before creating anything

The second case is confusing but harmless. Bumping pve-manager's
dependency on libpve-cluster-api-perl, which ships the API, would avoid
it.

With a QDevice, the name is also the CN of the cluster's certificate,
which qnetd checks. RFC 5280 limits a CN to 64 characters, so 32 is
fine.

I tested this on a three-node lab cluster. The API accepts a
32-character name and rejects 33. After I renamed the cluster to a
32-character name in corosync.conf, it stayed quorate, and pmxcfs,
pvecm status and the cluster status and join info APIs showed the new
name. I couldn't test a join or mixed versions there, so that part is
from reading the code. Please let me know if I missed something.

pve-cluster:

Kefu Chai (1):
  fix #6501: api: cluster create: allow cluster names up to 32 characters

 src/PVE/API2/ClusterConfig.pm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

pve-manager:

Kefu Chai (1):
  fix #6501: ui: cluster create: allow cluster names up to 32 characters

 www/manager6/dc/ClusterEdit.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

-- 
2.47.3