Installation manual

Shadowing a Volume
Adding a Shadow Volume (Target Switch)
CLI Storage-Management Guide 15-5
Allowing Modifications
The shadow-copy rule will be modifying the metadata in the target volume, so the
target volume must permit metadata modifications. This does not affect clients, who
will have read-only access to the volume. It only applies to the shadow-copy rule
itself. Use the
modify command to enable file modifications by the rule. (The modify
command was discussed in an earlier chapter; recall “Allowing the Volume to Modify
on Import” on page 9-9.)
For example, the following command sequence permits modifications in the
/acctShdw volume:
prtlndA1k(gbl)# namespace nemed
prtlndA1k(gbl-ns[nemed])# volume /acctShdw
prtlndA1k(gbl-ns-vol[nemed~/acctShdw])# modify
Automatically re-enable volume modify mode during NSCK rebuild? [yes/no] yes
prtlndA1k(gbl-ns-vol[nemed~/acctShdw])# ...
Adding a Share
A share in a shadow volume is configured the same way as any other
managed-volume share, but it is used differently. The shadow-copy rule will replace
all files on a shadow-volume share when it first runs; a share in a shadow volume is
used exclusively for file replicas from the source volume. To guard against a single
point of failure, we strongly recommend that you use shares from filers other than
those used for the source volume. For maximum protection, use shares from filers at
another ARX in the RON.
For example, the following command sequence adds two shares to the /acctShdw
volume:
prtlndA1k(gbl)# namespace nemed
prtlndA1k(gbl-ns[nemed])# volume /acctShdw
prtlndA1k(gbl-ns-vol[nemed~/acctShdw])# share back1
prtlndA1k(gbl-ns-vol-shr[nemed~/acctShdw~back1])# filer das-p1 path /lhome/exports/BU
prtlndA1k(gbl-ns-vol-shr[nemed~/acctShdw~back1])# enable
prtlndA1k(gbl-ns-vol-shr[nemed~/acctShdw~back1])# exit
prtlndA1k(gbl-ns-vol[nemed~/acctShdw])# share back2
prtlndA1k(gbl-ns-vol-shr[nemed~/acctShdw~back2])# filer das-p2 path /export/home/bkup
prtlndA1k(gbl-ns-vol-shr[nemed~/acctShdw~back2])# enable