Technical data

System Management Release Notes

5.18 Volume Shadowing for OpenVMS

The following release notes pertain to Volume Shadowing for OpenVMS.

5.18.1 Minicopy Version Required on All Nodes

7.3

OpenVMS Alpha Version 7.3 introduces minicopy support in Compaq Volume

Shadowing for OpenVMS.

To use this new feature of volume shadowing in an OpenVMS Cluster system,

OpenVMS Version 7.3, or an upgrade to OpenVMS Version 7.2–xx that will

contain this support, must be installed on every node. This restriction also

pertains to all storage controllers, such as the HS121, that use OpenVMS to serve

disks.

The upgrade to OpenVMS Version 7.2–xx that will include minicopy support is

expected to be available soon after the release of OpenVMS Version 7.3.

5.18.2 Multipath HSG/HSZ Disk Partitions and Volume Shadowing Restriction

V7.3

A partition of a multipath disk on an HSG80, HSG60, HSZ80, or HSZ70 controller

can be used as a member of a host-based volume shadow set (HBVS) if and only

if that disk is used exclusively for that partition. Speciﬁcally, the remaining space

on the partitioned disk cannot be used for another logical unit that is accessed

concurrently with the partition that is an HBVS member.

Failure to adhere to this restriction can result in:

• Problems mounting the shadow set

• Reduced data availability due to the unexpected removal of shadow set

members

Compaq expects to remove this restriction in the future.

5.18.3 Dismount of Client Using /MINICOPY; First Dismount Might Fail

V7.3

In an OpenVMS Cluster conﬁguration, when a member of a shadow set

is dismounted on a client and the minicopy qualiﬁer is speciﬁed, the ﬁrst

DISMOUNT command might fail.

Workaround

If the ﬁrst DISMOUNT command fails, repeat the command, as shown in the

following example:

$SHOW DEVICE DSA5555

Device Device Error Volume Free Trans Mnt

Name Status Count Label Blocks Count Cnt

DSA5555: Mounted 0 $80$DKA107: 7994646 1 18

$80$DKA107: (WILD3) ShadowSetMember 0 (member of DSA5555:)

$80$DKA302: (WILD3) ShadowSetMember 0 (member of DSA5555:)

$80$DKA303: (WILD3) ShadowSetMember 0 (member of DSA5555:)

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