[ClusterLabs] Fencing with a 3-node (1 for quorum only) cluster

[Digimer]

On 04/08/16 11:44 PM, Andrei Borzenkov wrote:
> 05.08.2016 02:33, Digimer пишет:
>> On 04/08/16 07:21 PM, Dan Swartzendruber wrote:
>>> On 2016-08-04 19:03, Digimer wrote:
>>>> On 04/08/16 06:56 PM, Dan Swartzendruber wrote:
>>>>> I'm setting up an HA NFS server to serve up storage to a couple of
>>>>> vsphere hosts.  I have a virtual IP, and it depends on a ZFS resource
>>>>> agent which imports or exports a pool.
> 
> ...
> 
>>
>> Note; If you lose power to the mainboard (which we've seen, failed
>> mainboard voltage regulator did this once), you lose the IPMI (DRAC)
>> BMC. This scenario will leave your cluster blocked without an external
>> secondary fence method, like switched PDUs.
>>
> 
> As in this case there is shared storage (at least, so I understood),
> using persistent SCSI reservations or SBD as secondary channel can be
> considered.

Yup. That would be fabric fencing though, or are you talking about using
it under watchdog timers? If fabric, then my worry is always a panic'ed
admin clearing it without properly verifying the state of the lost node.
With watchdog, it's fine, just slow.

-- 
Digimer
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