[comp.os.vms] LAT Allocation Problem

OAKLEY@BATTELLE.ARPA (Mark Oakley) (10/17/87)

We plan to provide our users the ability to make
outbound calls from any node in our cluster. To
better "pool" our resources, we plan to connect
the modems to a DECserver and let users allocate
a LAT port. There is a problem in that it is possible
to allocate the same port from different nodes
in the cluster. Does anyone have any ideas about
how to avoid this problem of multiple allocation?

So far I have tried setting the "cluster-available"
bit in the secondary-device-characteristics field
of the LAT ucb. This causes lock manager to take out
a system-wide lock on the resource. Unfortunately,
the resource name includes the node name (unless
the node is in an allocation class), so the locking 
does not work. If all of the nodes were in the same
allocation class, then I think the scheme would work.
Does anyone know what the consequences are of putting
all of the nodes (7 at our site) of a cluster in the
same allocation class?


Mark Oakley
Battelle Memorial Institute
505 King Ave.
Columbus, OH     43201-2693

(614) 424-7154

ARPAnet: oakley@battelle.arpa