To ensure the best performance with the Everpure FlashArray, please use this guide for the configuration and implementation of Linux hosts in your environment. These recommendations apply to the versions of Linux that we have certified as per our FlashArray Compatibility Matrix.
Important:
Due to a change in path priority detection in versions between 0.6.2 and 0.9.7 of multipath-tools (or device-mapper-multipath), customers not upgrading to at least 6.5.5 or 6.6.4 must add the statement detect_prio "no" into their multipath.conf. The default configuration otherwise will try to override the 'alua' prioritizer and replace it with 'sysfs' despite 'alua' being specified in multipath.conf. Failure to do so will result in half of the paths remaining in the ALUA state of Active/Non-optimized after the upgrade is completed.
To find the <Dev_name> you can use multipath -ll to see what it is on each path. In the following example the first part of the name starts with "sd". for example sdf, sdx, sdl, and sdr.
[root@host ~]# multipath -ll
3624a9370ffa9a01386b3410600011036 dm-6 PURE,FlashArray
size=35G features='0' hwhandler='0' wp=rw
`-+- policy='queue-length 0' prio=1 status=active
|- 1:0:0:9 sdf 8:80 active ready running
|- 0:0:1:9 sdx 65:112 active ready running
|- 1:0:1:9 sdl 8:176 active ready running
`- 0:0:0:9 sdr 65:16 active ready runningThe following command also supplies the <Dev_name>.
[robm@robm-rhel7 ~]$ grep PURE /sys/block/sd*/device/vendor
/sys/block/sdb/device/vendor:PURE
/sys/block/sdc/device/vendor:PURE
/sys/block/sdd/device/vendor:PURE
/sys/block/sde/device/vendor:PURE