[ClusterLabs] 2-Node Cluster Pointless?

[Digimer]

On 18/04/17 04:08 AM, Christine Caulfield wrote:
> 
>>
>> This isn't the first time this has come up, so I decided to elaborate on
>> this email by writing an article on the topic.
>>
>> It's a first-draft so there are likely spelling/grammar mistakes.
>> However, the body is done.
>>
>> https://www.alteeve.com/w/The_2-Node_Myth
>>
> 
> An excellent article. One small point I noticed though. "Fabric Fencing"
> more usually refers to SCSI reservation fencing (hence it does not
> isolate the node from the cluster, just shared storage) - often  over
> Fibre-channel (hence "fabric") though I believe iSCSI supports it too.
> 
> While this doesn't take the node out of the cluster it does prevent
> damage to shared storage and allows non-clustered applications to
> continue working if it's just the cluster network interconnect that has
> failed.
> 
> IMO SCSI fencing should never be used on a 2 node cluster for reasons
> you have already described very clearly.
> 
> Chrissie

I was fairly generic on that term because I've seen (and even wrote
one!) where snmp was used to drop the ethernet switch ports to a target.
It is worth clarifying though.

cheers

-- 
Digimer
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