[Linux-cluster] Starter Cluster / GFS

[Gordan Bobic]

Nicolas Ross wrote:
>>> With a quorum disk, you can in fact have one node left and still have
>>> quorum. This is because the quorum drive should have (node-1) votes,
>>> thus always giving the last node 50%+1 even with all other nodes 
>>> being dead.
>>
>> I've never tried testing that use-case extensively, but I suspect that 
>> it is only safe to do with SAN-side fencing. Otherwise two nodes could 
>> lose contact with each other and still both have access to the SAN and 
>> thus both be individually quorate.
> 
> I our case, a particular node will run a particular service from a 
> particular directory in the disk. So, even if 2 nodes looses contacts to 
> each other, they should not end up writing or reading from the same 
> files. Am I wrong ?

If two nodes lose contact to each other, one will fence each other and 
shut it down.

If you don't need concurrent access, then why do you need a cluster file 
system?

Gordan