Re: Linux Cluster using shared scsi

[Doug Ledford <dledford@redhat.com>]

Mike Anderson wrote:
> 
> Doug,
> 
> A question on clarification.
> 
> Is the configuration you are testing have both FC adapters going to the same
> port of the storage device (mutli-path) or to different ports of the storage
> device (mulit-port)?
> 
> The reason I ask is that I thought if you are using SCSI-2 reserves that the
> reserve was on a per initiator basis. How does one know which path has the
> reserve?

Reservations are global in nature in that a reservation with a device will
block access to that device from all other initiators, including across
different ports on multiport devices (or else they are broken and need a
firmware update).

> On a side note. I thought the GFS project had up leveled there locking / fencing
> into a API called a locking harness to support different kinds of fencing
> methods. Any thoughts if this capability could be plugged into this service so
> that users could reduce recoding depending on which fencing support they
> selected.

I wouldn't know about that.

-- 

 Doug Ledford <dledford@redhat.com>  http://people.redhat.com/dledford
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