Hot-Add MD1200 to MD3220i

I have been working with the MD storage arrays for a while now, specifically the MD3220 and MD1220 units... I can tell you for certain that you can hot-add the MD12XX without any issues... The only potential issues you'd run into would be if there's a hardware problem with the MD12xx unit... otherwise, once you connect it, the ESM modules will come online and the MD3220 will scan the array to inventory the drives and make them available for use.

Also... I'm assuming you're running redundant controllers in the MD3220, correct?  If so, you should be able to stagger rebooting the controllers without taking the array down.  You should log into the MD Storage Manager software and take the controllers offline one at a time.  Once you've taken one offline you can unplug, count to 30 and replug.  Once it fully boots, make sure to bring it online in the MD Storage Manager software then repeat the process on the second controller.

I've walked through that process many times without issues... Dell's storage support group are the ones who walked me through that method.

jpgobert,

Great stuff - thanks very much for this very helpful info.

Just a couple of further questions if you don't mind:

1. When you say " if there's a hardware problem with the MD12xx unit... " whats the worst that could happen? It's brand-new, so should be OK. However, if it did turn out to be defective (as per your experience), would that pose any threat to the MD3220i or it's current configuration?

2. I do have redundant RAID controllers so no problems. I have MPIO configured on my VMWare cluster to I should be able to loose one and fail-over right?

3. When you talk about unplugging, counting to 30 and re-plugging, do you mean something like the following?

a) Connect the powered-down MD1220 to the powered-up MD3220i as per documentation.
b) Power-up MD1220
c) Power-down controller A on the MD3220i, wait 30 secs then power up
d) Do the same with controller B once controller A is back online

Just a little confused about the "unplug, count to 30 and replug" part. Would I need to unplug the controller from the chassis?

Many thanks in advance,

Olly

1. When you say " if there's a hardware problem with the MD12xx unit... " whats the worst that could happen? It's brand-new, so should be OK. However, if it did turn out to be defective (as per your experience), would that pose any threat to the MD3220i or it's current configuration?

Nothing about your current configuration will change no matter what... Let's say that one of the EMM modules in the MD1220 is bad for some reason... when the MD3220 tries to bring the unit online it will test and inventory everything... if it finds a problem it will throw a flashing amber and you'll be able to see why in the MD Storage Manager software.  Even if something like that were to happen it won't affect your existing configuration... Dell will always tell you that best practice would be to make a backup of your config through the MD Storage Manager software before making any major changes (not a bad idea and it's a quick operation).

The worst case scenario would be that you'd need to unplug the MD1220 and contact support if you ran into a bad unit.

2. I do have redundant RAID controllers so no problems. I have MPIO configured on my VMWare cluster to I should be able to loose one and fail-over right?

Yes... just make sure to take the controller offline in the MD Storage Manager software so that it is a clean operation.  

3. When you talk about unplugging, counting to 30 and re-plugging, do you mean something like the following?

a) Connect the powered-down MD1220 to the powered-up MD3220i as per documentation.
b) Power-up MD1220
c) Power-down controller A on the MD3220i, wait 30 secs then power up
d) Do the same with controller B once controller A is back online

Just a little confused about the "unplug, count to 30 and replug" part. Would I need to unplug the controller from the chassis?

Sorry I should have been more clear on that... the process Dell has always had me follow is to connect the MD1220 while powered off to the MD3220.  Once connected and you double check your cabling you can power on the MD1220.  

If you're concerned and want to do it one controller at a time you can do the following though you really don't have to:

a)  Take controller 0 offline on the MD3220 and wait for that operation to complete.
b)  Unplug controller 0 from the MD3220
c)  Connect the SAS cable from the unplugged MD3220 controller 0 to EMM 0 on the MD1220.
d)  You can unplug EMM 1 from the MD1220 at this point so that only EMM 0 is plugged in.
e)  Power on the MD1220 and give it 30 seconds or so to settle.
f)  Plug controller 0 back into the MD3220 and bring it back online in the MD Storage Manager software.
g)  Once everything settles and you confirm that you see the MD1220 in the MD Storage Manager software and you have no amber lights, take controller 1 offline.
h)  Once controller 1 is offline, connect EMM 1 to controller 1.
i)  Plug EMM 1 into the MD1220
j)  Plug controller 1 back into the MD3220

Let everything settle and verify in MD Storage Manager that everything is online and happy with no amber lights.

Fantastic. I'll do this as soon as I am able.

Just one final question, if you don't mind (which arguably should be on a different thread...!)

Before I do this, I felt it would be best to upgrade the firmware in the MD3220i. Its currently on version 07.75.28.60, which is one version away from the latest (being version 07.80.41.60).

The FW upgrade process looks simple enough. Have you ever experienced any issues upgrading? I understand it performs the update on one controller, which then, once up and running with the new firmware, copies it over to the other.

I'm just worries about corrupting the controllers should the update go wrong. Am I being neurotic? :-)

Thanks again - and the point are yours this time!

Brilliant. Thanks again for everything - I'll let you know how it goes!