Delete devices to create unprotected BCVs

Question

Issue: I need enough unprotected (or mirrored) BCVs so that we have the ability to perform meta expansions on our sym, a DMX-4 running 5772.85.

Configuration: All drives in the array are configured as RAID5 (3+1). A standard hyper size is used on all drives for building metas: 31.6GB. The remaining space on the drives is filled with 5.0GB hypers. There are 160 146GB drives for production, 64 300GB drives for BCVs and clones, and 68 500GB drives for clones. These three different drive types correspond to three different disk groups and the hypers are spread across all the drive in each disk group.

Problem: Since all of the drives are configured as RAID5 (3+1) and hypers are created on every drive I need to delete devices and break the RAID configuration on enough drives to create the free space necessary to allow us to perform meta expansions. My concern is that I will need to delete some existing metas in use to free up enough drives required for meta expansion BCVs.

Any thoughts on the best way to approach this?

xe2sdc · Accepted Answer

You already answered your own question ..

Since symconfigure can't leverage RAID5-BCVs while expanding your metas or converting them, you have to choose between Unprotected and 2-Way-Mir BCVs.

In my experience I never had issues with unprotected BCVs, however it's always possible that a drive fails during a meta expansion, leaving you without either the original or the BCV copy of your beloved data.

What do you think I'd suggest you ??

Please note that EMC always suggests to make a backup of your beloved metavolume before expanding/converting it via symconfigure. If you are brave enough, you can try without a backup and with unprotected BCV. And if something does not work as expected, remember that you (as any other storage administrator) always have an open ticket for a flight to Caracas in your pocket

xe2sdc · Answer

Any thoughts on the best way to approach this?

I see options ...

1) buy drives and configure BCV on them

2) use your favourite spreadsheet and throw in "symdisk -sid xxx -v -hypers -gaps list" output.. Now try to find "adjacent" hypers that you may delete .... And knock wood

dynamox · Answer

would you use unprotected BCV's or 2-way mirror BCVs ..so during expansion you don't lose data in case disk containing your unprotected BCV fails ?

AranH1 · Answer

Heh heh

, yeah option 1 was the first thing I thought of as it sounded really simple and easy.

Option 2 was what I was afraid of... it makes my head hurt just imagining the digging I will have to do to find the 'adjacent' hypers.

dynamox · Answer

cool ...now get your bean counter to cut you a PO to get some disks

AranH1 · Answer

We don't use SRDF, just RecoverPoint, so there are mirror positions available.

AranH1 · Answer

Ideally I would use mirrored BCVs to protect data during expansion.

dynamox · Answer

that's what i was thinking ...i remember i had one situation where i could not do that because i ran out of mirror positions, so i think i had to either split my SRDF link or my R1-BCV ...don't remember exactly, but something check.

AranH1 · Answer

I was trying to avoid that, they are still reeling from purchasing the DMX last year .Maybe I can slip it in with our next coffee purchase.... we drink a lot of coffee out at the datacenter...

xe2sdc · Answer

I think this is still option 1

.. Reduce coffee to buy disks .. a good tradeoff

However in case you wonder, I'm a great beancounter !! And I count for free... Given that you pay the flight and the hotel

-s-

AranH1 · Answer

Please note that EMC always suggests to make a backup
of your beloved metavolume before
expanding/converting it via symconfigure. If you are
brave enough, you can try without a backup and with
unprotected BCV. And if something does not work as
expected, remember that you (as any other storage
administrator) always have an open ticket for a
flight to Caracas in your pocket

LOL... man, you get the correct points for that comment

But shame on you for suggesting we lower the coffee budget. You're Italian! You of all people should appreciate the need for good coffee.

dynamox · Answer

Blue Mountain coffee from Jamaica ...that's what i am talking about ..Ya mon

xe2sdc · Answer

Ehehehe AranH I was simply riding your original idea

.. I can't live without coffee .. Italian coffee I mean !!

When I've been outside Italy for the very first time I've been in Sweden .. I had "coffee" for 4 days but on Thursday I had to drink a real coffee .. So I went to an "Italian Restourant" with a big "Espresso Lavazza" brand on the sign. Lavazza is a well known italian coffee brand.

I had all my lunch with only one thing in my mind .. a cup of REAL coffee ...

At the very end of the lunch the girl asked me "Do you want an EXPRESSO" ??

And I answered "YES!"...

She come back after a few minutes (walking from behind my shoulders) ... And served me a JAR of water that looked like coffee ..

That's how I learned that italian coffee is quite different from coffee almost everywhere in the world. I learned the hard way

AranH1 · Answer

Blue Mountain coffee from Jamaica ...that's what i am
talking about ..Ya mon

That is good stuff, but not worth the price in my opinion. Supply and demand I guess. Give me Celebes Kolossi or Tanzania Peaberry.

AranH1 · Answer

I live in the Northwest of America which is famous for the plethora of espresso stands everywhere and the birth of the biggest espresso chains in the country (which have since switched to crappy automatic machines and now the espresso sucks). I live on the stuff!

When I was at EMCWorld a few weeks ago I was in line at Starbucks behind a guy from Italy and he asked for "Italian" coffee. So they gave him a double espresso and as he walked away he tasted it and made a sour face and looked very disappointed. I felt like running up to him and apologizing on behalf of America for that. Starbucks makes the worst espresso. Poor guy....

Before working in IT I was a cook in a Greek restaurant run by a family of immigrants. We served Greek (Turkish) coffee there. That was awesome! That stuff will put hair on your back!

Symmetrix

Delete devices to create unprotected BCVs

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