Cluster with 1 node only?

yos

Active Member
Sep 11, 2019
5
0
41
41
Hi

I have a 3 node cluster but for heating reasons, as the temperature of the room is getting high in the summer, I would like to temporary shutdown 2 nodes and have my setup running on one node only. The questions are:

1. is it healthy to run a cluster with one node?
2. what are the consequences of running the `pvecm expected 1` command?
3. when the temperature are better, will i need to do `pvecm expected 2`?

thx
 
This all depends on a few things.
  1. The filesystem used between nodes for your containers/virtual machines
    Ceph can be scaled down depending on settings - but will need 2 mons to run in a 3 node cluster (there are unsafe workarounds)
  2. Quorum between nodes
    Corosync has 'last man standing' options you could configure as-well as using node votes within the config
BEWARE!! There be dragons!!