Here at Contegix we use a wide range of EqualLogic storage arrays, from standalone PS4000 series units for small scale deployments, to large clustered groups of PS6000 and PS6500 series “sumo” arrays for our cloud infrastructure.  After a lengthy investigation of storage arrays prior to launching our cloud platform in 2009 we ultimately settled on EqualLogic as our preferred cloud storage vendor for many reasons including performance, scalability, feature set, and product roadmap.

While much of the administration of these units can be done via their rather full featured GUI, there will ultimately come a time when an administrator will need to dig a bit deeper.  Certainly one clear case is for large scale deployments where point and click setup and configuration is no longer scalable.  Even for the small environment (or just the curious administrator) there are a few good reasons for digging under the covers to the deep dark world of the CLI.

The EqualLogic CLI can be easily and securely accessed via SSH using the same administrator level credentials used for the GUI.  Once in, you will find a pretty typical CLI feel.  Full latest documentation can be accessed from your Dell EqualLogic support login, or you can still access an older version of the docs without a login at http://psonlinehelp.equallogic.com/V3.3/prcli_intro.htm.  If at any point you get lost, you can always use the “help” and “tree” commands for a list of available commands.  Another useful approach to learning the CLI is to use the “save-config” command and transfer your configuration off to see what commands will yield a configuration like your array is currently running.  As you can see, this approach for configuration can be a life saver when large scale deployment and repeatability is a requirement.

Now for the fun part.  Insert your favorite “proceed at your own risk” disclaimer here.  While the following can be quite useful and powerful, EqualLogic will obviously tell you that you should not do this unless directed by their technical support personnel.  Well, consider yourself warned and read on… if you dare.

As with all CLI environments, there is always a way to dig a bit deeper under the covers than the standard CLI.

ccc-dc01-g01> support exec bash
You are running a support command, which is normally restricted to PS Series Tec
hnical Support personnel. Do not use a support command without instruction from
Technical Support.
cli-child-3.2#

As with so many other devices on the market today, we have found our way down to the juicy NetBSD core.

cli-child-3.2# uname -a
NetBSD ccc-dc01-g01-m01 1.6.2 NetBSD 1.6.2 (EQL.PSS) #0: Sun Sep 19 14:43:14 EDT 2010     build@m58:/buildarea/V5.0.2__Sun_Sep_19_2010_14_30_05_EDT/bin/destdir.sbmips.release/EQL.PSS xlrmips

While there is little that can really be done here by the average administrator other than obviously satisfying some urges of curiosity, the one quite useful command (of which the output has been curiously omitted from the GUI) is “raidtool”.

cli-child-3.2# raidtool
Driver Status: Ok
RAID LUN 0 Ok.
14 Drives (0,2,4,6,8,1,3,5,7,9,10,11,12,13)
RAID 50 (64KB sectPerSU)
Capacity 11,942,405,603,328 bytes
RAID LUN 1 Ok.
14 Drives (14,15,46,17,18,19,20,21,22,23,24,25,26,27)
RAID 50 (64KB sectPerSU)
Capacity 11,942,405,603,328 bytes
RAID LUN 2 Ok.
14 Drives (28,29,30,31,32,33,34,35,36,37,38,39,47,41)
RAID 50 (64KB sectPerSU)
Capacity 11,942,405,603,328 bytes
RAID LUN 3 Ok.
04 Drives (42,43,44,45)
RAID 5 (64KB sectPerSU)
Capacity 2,985,601,400,832 bytes
Available Drives List: 16,40

While the output above may not seem overly interesting in its current state, it is however quite useful when the array is rebuilding one of its RAID LUNs with a hot spare.  In that case, the output will report the completion percentage of that rebuild.  The above example shows running it from the bash prompt, but it could also be run directly from the standard CLI prompt using “support exec raidtool”.

Another other hidden CLI command which can be quite useful in the right circumstances is one for tuning the TCP window size for replication traffic.  While LAN level replication has always worked perfectly right out of the box for us, there are certain scenarios where WAN replication may require a bit of TCP stack tuning.  This is certainly one of those “don’t do this unless instructed by EqualLogic support” sort of changes since it can negatively impact your performance if not done under the right circumstances, but if you want to give it a shot in a non-production environment of course, then have at it.

ccc-dc01-g01> support repl-window-size
You are running a support command, which is normally restricted to PS Series Tec
hnical Support personnel. Do not use a support command without instruction from
Technical Support.
Repl-Window-Size ::72KB
ccc-dc01-g01> support repl-window-size 1024
You are running a support command, which is normally restricted to PS Series Tec
hnical Support personnel. Do not use a support command without instruction from
Technical Support.
ccc-dc01-g01> support repl-window-size
You are running a support command, which is normally restricted to PS Series Tec
hnical Support personnel. Do not use a support command without instruction from
Technical Support.
Repl-Window-Size ::1024KB

Be sure to restart any replication transfers in progress after making the change on the receiving end to realize the change.