[Info-vax] Idiots Guide To Clustering

[Michael Moroney]

H Vlems <hvlems at freenet.de> writes:

>On 17 mrt, 17:36, moro... at world.std.spaamtrap.com (Michael Moroney)
>wrote:
>> H Vlems <hvl... at freenet.de> writes:
>> >Basically what happens is that a few parameters in sys
>> >$system:modparams.dat are set correctly.
>> >ALLOCLASS : each cluster member in a VAX NI cluster must have a unique
>> >and non-zero value
>>
>> ALLOCLASS does not need to be nonzero.  A zero ALLOCLASS will change
>> how a member's disks are named in the cluster.  They will be node$ddnu
>> rather than $m$ddnu.  It was the norm during the time when local area
>> vaxclusters with many nonvoting satellites to have the satellites use
>> alloclass 0.
>>
>> You want ALLOCLASS nonzero for any node serving shared storage, but I
>> don't remember if that's even necessary with port allocation classes
>> for shared SCSI.

>Correct, but one might be tempted to set up a shadowset across the LAN.

Yes, if the node is going to serve a disk to a shadowset, that disk must
have a nonzero alloclass. name$ddcu disks (zero alloclass) cannot be
shadowset members.  A node with a zero alloclass can still mount shadowsets.