nomenclature of new lun

[RiclyLeRoy]

In service guard, when I add new Lun and I present It to all hosts of my cluster, I ask if HP-UX should have to create the same device special file for every hosts  e.g. /dev/disk/disk30. In this way the same volume group, regardless of host where It's active, reference always the same logic disk (in example /dev/disk/disk30)

This one is not occurring in my environment, the numeration of new disk is different for every disk e.g. /dev/disk/disk32 /dev/disk/disk36 What's happening ?

[georgek_1 · Accepted solution]

Hello RiclyLeRoy,

This is the expected behavior, where the lun shared across SG nodes would have different disk dsfs (device special files).
Installation/availability of Service guard alone wouldn't make same disk dsfs for luns across the nodes , unless you configured Cluster-Wide Device Special Files (cDSFs).
Configuration of cDSFs ensure that each storage devices used by the cluster has unique device file name across the nodes .

For example, the lun may be /dev/disk/disk30 at one node while it would be /dev/disk/disk25 at the other , but with cDSF enables, it would be /dev/cdisk/disk1 across both nodes .

You may refer Service guard Admin guide from URL: https://support.hpe.com/hpesc/public/docDisplay?docLocale=en_US&docId=a00062147en_us
Please go through the sections mentioned below along with # man cmsetdsfgroupto get familiar with cDSFs, and how to configure them .
About Cluster-Wide Device Special Files (cDSFs)
Creating Cluster Wide Device Special Files
# man cmsetdsfgroup 
 
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