Installation manual

Adding a Managed Volume
Dividing the Import into Multiple Scans
CLI Storage-Management Guide 9-7
A multi-scan import is appropriate for an installation with a short cut-in window.
From gbl-ns-vol mode, use the
import multi-scan command to separate the file scan
from the directory scan:
import multi-scan
This does not have any affect on an import that is currently underway; it applies to
future imports only.
For example, this command sequence prepares the “medarcv~/lab_equipment”
volume for a multi-scan import:
bstnA6k(gbl)# namespace medarcv
bstnA6k(gbl-ns[medarcv])# volume /lab_equipment
bstnA6k(gbl-ns-vol[medarcv~/lab_equipment])# import multi-scan
bstnA6k(gbl-ns-vol[medarcv~/lab_equipment])# ...
Protecting Metadata During Import
A fully-imported volume protects its metadata by recording all metadata transactions
in battery-backed, Non-Volatile RAM (NVRAM). After an unexpected reboot or
failover, the volume can retrieve these transaction records from NVRAM and use
them to recover all in-flight metadata changes. By default, the volume speeds up its
import by skipping these metadata-protection measures until the import is complete.
An unexpected reboot or failover during import therefore causes the import to restart.
NFS clients who may have been connected during the import would have to re-mount
the volume because the re-import changes all NFS filehandles. CIFS clients would
not have a noticeable interruption in service.
You can set the volume to protect its metadata during its next import. This guards
against the unlikely event of a reboot, but at the cost of a slower import. From
gbl-ns-vol mode, use the
import protection command to protect volume metadata
during import:
import protection
As with the
import multi-scan command, this does not affect a currently-running
import.
For example, this command sequence protects the metadata in the “wwmed~/acct”
volume during import: