New cluster planning

[btspce]

We are migrating servers to proxmox and have a few questions regarding clustering and if this will work.
We will not be using HA and servers will be using local lvm thin storage.
Currently there are two identical pve 8.0.3 hosts (PVE1 and PVE2). PVE1 is in production running vm's. PVE2 is newly installed and only network and local storage has been configured.
As I understand it we must create the cluster on PVE1 running vm's as the other will inherit all configs from that host.

Will the vm's keep running on PVE1 when PVE2 joins the cluster? (We don't want quorum issues.)
Can we start adding vm's to the empty second host after it has joined the newly formed cluster before we join with the third host ?
WIll the cluster automatically be configured to require two hosts up at all times after the third host joins ?

 

[alexskysilk]

Will the vm's keep running on PVE1 when PVE2 joins the cluster?

yes

Can we start adding vm's to the empty second host after it has joined the newly formed cluster before we join with the third host ?

yes

WIll the cluster automatically be configured to require two hosts up at all times after the third host joins ?

not... exactly, but a cluster cannot stand with only one member since it wont have quorum. If two nodes are out, the third one will be fenced and reboot. once back up, the first node ready will become master, and the others will join it when coming back.

 

[btspce]

Thanks alexskysilk !

 

[bbgeek17]

Will the vm's keep running on PVE1 when PVE2 joins the cluster?

VMs will not migrate or rebalance on their own. You will need to either specifically mark them for HA, or direct PVE to migrate using GUI/CLI/API.

(We don't want quorum issues.)

Once you join the second host, loosing one of the hosts will cause a loss of quorum and you will experience service degradation.

Can we start adding vm's to the empty second host after it has joined the newly formed cluster before we join with the third host ?

There is no limitation in the code to prevent you from adding new VMs to either of the hosts in the cluster.

WIll the cluster automatically be configured to require two hosts up at all times after the third host joins ?

The cluster functionality will force a Read Only mode in both the case of loosing one of two nodes, or two of 3.
Its statistically less likely that you will loose 2 out of 3, hence the majority is more likely to be present to allow split-brain resolution.

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