[SOLVED] HA shutdown policy

[Mayank006]

I was going through the HA shutdown policy.
Can you explain the difference between Conditional and Failover?

Is failover a subset of Conditional?

 

[bbgeek17]

https://pve.proxmox.com/wiki/High_A... requested, and changes behaviour accordingly.

this may help

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[Mayank006]

https://pve.proxmox.com/wiki/High_Availability#:~:text=The Conditional shutdown policy automatically detects if a shutdown or a reboot is requested, and changes behaviour accordingly.

this may help

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

Yes, I saw that, I just wanted to know if changing settings to only failover can improve system efficiency in terms of ha?

 

[bbgeek17]

Yes, I saw that, I just wanted to know if changing settings to only failover can improve system efficiency in terms of ha?

You have to define what exactly you mean by "system efficiency".

Failover shuts down services (VMs) and attempts to wait for the same node be back online. If its not, for some defined time, it will try to restart services elsewhere.

Conditional attempts to detect whether the node was shutdown or rebooted, and based on the outcome follows Shutdown or Reboot policy

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[Mayank006]

You have to define what exactly you mean by "system efficiency".

Failover shuts down services (VMs) and attempts to wait for the same node be back online. If its not, for some defined time, it will try to restart services elsewhere.

Conditional attempts to detect whether the node was shutdown or rebooted, and based on the outcome follows Shutdown or Reboot policy

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

I thought failover was not part of the shutdown. Looks like that condition will check failover, shut down, reboots, etc.

 

[bbgeek17]

I thought failover was not part of the shutdown. Looks like that condition will check failover, shut down, reboots, etc.

My reading of

Failover
This mode ensures that all services get stopped, but that they will also be recovered, if the current node is not online soon. It can be useful when doing maintenance on a cluster scale, where live-migrating VMs may not be possible if too many nodes are powered off at a time, but you still want to ensure HA services get recovered and started again as soon as possible.

Is that this is done when one expects to do maintenance on large number of hosts in the cluster, therefore there will be no enough resources to move all VMs. Its also expected that VMs bouncing between nodes would cause more problems than just having them down for the duration of maintenance window.
My understanding is that "Failover" is not an action of what to do with VM, but rather an expectation of upcoming work.
The VMs will be turned off and NOT immediately recovered, but rather the HA system will wait for the hosting node to come back.

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox