Datacenter > HA does show if a node is in maintenance mode.
root@nx1a:~# ha-manager status
quorum OK
master nx1d (active, Thu May 16 20:31:13 2024)
lrm nx1a (idle, Thu May 16 20:31:17 2024)
lrm nx1b (idle, Thu May 16 20:31:18 2024)
lrm nx1c (maintenance mode, Thu May 16 20:31:19 2024)
lrm nx1d...