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EMC Power Path on Linux

To create devices	powermt config
To view devices	powermt display dev=all
Check/remove devices	powermt check
View paths	powermt display paths
Check/repair paths/trespassed disks	powermt restore
Set policy (ie CLARiiON)	powermt set policy=co dev=all
Rename device	emcpadm rename -s {source} -t {target}
View used devices	emcpadm getusedpseudos
Release old devices	powermt release

To make mappings consistent across servers in a cluster:

One one server	emcpadm export_mappings -f /tmp/mappings
On every other cluster node, first check what would be changed	emcpadm check_mappings -f /tmp/mappings
Then apply changes	emcpadm import_mappings -f /tmp/mappings
Double-check your work	emcpadm check_mappings -f /tmp/mappings

Fix Missing paths

First try:

powermt restore

If that fails:

/sbin/start_dev
/net/swdepot/software/scripts/rescan_luns.sh

Adding LUNs without a reboot:

Run this script:

/net/swdepot/software/scripts/rescan_luns.sh

The above shell script performs the following steps for you: Note: you do not need to perform the following steps if you ran the shell script above. This is just for your information.

First, you need to get the HBA’s to issue a LIP and then a re-scan

echo 1 > /sys/class/fc_host/{host#}/issue_lip 
echo "- - -" > /sys/class/scsi_host/{host#}/scan

Do this for every host path (usually just 'host0' and 'host1')

Now you just need to tell Power Path to go do its normal discovery

powermt config

If you do a display, you should see the new LUN.

powermt display dev=all