High availability - host failure number
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Hi,
I have enabled HA in my pool of 4x host running
xe pool-ha-enable heartbeat-sr-uuids=<UUID>
.QUESTION: Do I also need to set the maximum host failure number? As I have 4x hosts, am I correct to think that I will need to set it to 3?
[09:31 uk ~]# xe pool-ha-compute-max-host-failures-to-tolerate 4
Do I simply leave everything as is or do I manually set the value to 3 with
xe pool-param-set ha-host-failures-to-tolerate=**3** uuid=<Pool_UUID>
Thank you
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Hello @fred974
Did you find your answer ?
I don't understand clearly how a 4 nodes pool can tolerate 4 nodes dead.
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Think of it like this:
If you have 4 hosts, each host maximum usage will be 25% of the total - How much of that % do you want to reserve in case of a failed host?
Personally, I'd like to have the number set to 1 host (25%) because that means im able to use 3 hosts and the 4th hosts resources would be reserved in case of a failure. -
Hello, @nikade
Yeah i think like this already, but i'm surprised by the result of the calcul.
I should i have either: 3 nodes which can die, or "1", but i should not have the same number right ?
in my case, i run the command in a 3 hosts cluster and it return me
3
as value. which disturb me.Best regards,