Set System Parameters for Volume Shadowing
(New Installations Only; Optional)
If you plan to form a shadow set, you must add system parameters
to the SYS$SYSTEM:MODPARAMS.DAT file. Add the following lines to
the bottom of the MODPARAMS.DAT file:
SHADOWING=2
!Enable volume shadowing SHADOW_SYS_DISK=4097
!Enable shadowing of the system disk and allow for mini-merge SHADOW_SYS_UNIT=n !Optional: default is 0, which creates DSA0 SHADOW_MAX_COPY=4
!Allow up to 4 shadow copies to be going on at the
same time SHADOW_MAX_UNIT=500 !Allow up to 500 shadow
sets (includes dismounted and unused) ALLOCLASS=x !This number must be unique per node in
the cluster; !sets up $x$DSAn
In an OpenVMS Cluster, specify a unique ALLOCLASS value for
each node. For more information about these and other system parameters
you can set for volume shadowing, refer to the HP Volume Shadowing for OpenVMS guide.
For more information about setting ALLOCLASS for clusters, refer
to the HP OpenVMS Cluster Systems manual.
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