Installation manual

Shadowing a Volume
Configuring a Shadow-Copy Rule (Source Switch)
CLI Storage-Management Guide 15-23
For example, this command sequence limits transfers by the rule, “DRrule,” to five
million BPS:
bstnA6k(gbl)# namespace wwmed
bstnA6k(gbl-ns[wwmed])# volume /acct
bstnA6k(gbl-ns-vol[wwmed~/acct])# shadow-copy-rule DRrule
bstnA6k(gbl-ns-vol-shdwcp[wwmed~/acct~DRrule])# bandwidth-limit 5M
bstnA6k(gbl-ns-vol-shdwcp[wwmed~/acct~DRrule])# ...
Removing any Bandwidth Limit
Use the no bandwidth-limit command to allow the rule to use unlimited bandwidth for
its transfers:
no bandwidth-limit
For example, this command sequence removes any bandwidth limit from the
“insurDR” rule:
bstnA6k(gbl)# namespace insur
bstnA6k(gbl-ns[insur])# volume /claims
bstnA6k(gbl-ns-vol[insur~/claims])# shadow-copy-rule insurDR
bstnA6k(gbl-ns-vol-shdwcp[insur~/claims~insurDR])# no bandwidth-limit
bstnA6k(gbl-ns-vol-shdwcp[insur~/claims~insurDR])# ...
Changing the Threshold for Delta Transfers (optional)
The shadow-copy rule generally copies the delta for each file that changed. That is,
the source and shadow files are compared on a block-by-block basis, and only the
blocks that changed are sent to the shadow volume. For large files, this saves network
bandwidth. As files get smaller, the bandwidth savings can be offset by the cost of
computation time.
By default, the shadow-copy rule performs delta transfers for files 100 MegaBytes or
larger. Files smaller than 100 MegaBytes are transferred in their entirety. Note that
both versions of the file (source and shadow) must exceed the delta threshold for the
delta transfer to take place.