HP OpenVMS Systems Documentation

Content starts here Evaluating Condition Values Returned by $DISMOU and $MOUNT
HP Volume Shadowing for OpenVMS: OpenVMS Version 8.4 > Chapter 5 Creating and Managing Shadow Sets with System Services

Evaluating Condition Values Returned by $DISMOU and $MOUNT

This section discusses the condition values returned by the $DISMOU and $MOUNT system services that pertain to mounting and using shadow sets. For a complete list of the condition values returned by these services, see the HP OpenVMS System Services Reference Manual.

If $MOUNT returns the condition value SS$_BADPARAM, your item list probably contains one of the following errors:

  • The virtual unit specified in one of your MNT$_SHANAM item descriptors contains a name other than DSAn:.

  • A MNT$_SHAMEM item descriptor appears in the item list before any MNT$_SHANAM item descriptor.

  • Your item list contains a MNT$_SHANAM item descriptor, but it is not followed by the item descriptor MNT$_SHAMEM.

  • A MNT$_DEVNAM item descriptor appears in the item list in the middle of a series of item descriptors that specify a single shadow set. You can construct a volume set that contains one or more nonshadowed disks, as well as one or more shadow sets. However, when you use the MNT$_DEVNAM item descriptor to specify the nonshadowed disk, it must not appear between the MNT$_SHANAM item descriptor that specifies a virtual unit and the item descriptors that specify the members of the shadow set that the virtual unit represents.

  • The following list contains possible status messages that $MOUNT can return when mounting and using shadow sets:

    • SS$_VOLINV (label mismatched)

    • SS$_SHACHASTA (shadow state change occurred during a mount operation)

    • SS$_MEDOFL (physical unit not accessible)

    • SS$_INCSHAMEM (physical disk incompatible for shadow set)

See also Appendix A for shadowing-related status messages.