Tag Archives: VNX - Page 3

How to start copy to hotspare manually

Posted by on November 11, 2014 5 comments
Hard Drive

I recently had to manually invoke a hot spare in a VNX 5200, but in Unisphere the option was greyed out.

Unisphere_No-CopyToHotSpare

On the CLI the command wasn’t supported. Now what?

CopyToHotSpare_fail

According to https://support.emc.com/kb/184890 the proper command is now

naviseccli -h [ip of one SP] copytodisk [source-disk] [hot spare]

CopyToDisk_Success

Using the “getdisk” command will show you the actual rebuild has started.

Bare in mind that the way to address disks is in the format “Bus_Enclosure_Disk”, so for example 1_2_3 means disk 3 (the 4th disk) in enclosure 2 on bus 1.

In Unisphere you can actually see the progress of the rebuild:

Disk Rebuild in Unisphere

Increased response times on VNX when using Windows 2012

Posted by on July 1, 2014 1 comment

Windows 2012 can cause higher response times on VNX

When Windows 2012 issues Trim or Unmap commands to thin LUNs on a VNX, the Storage Processor response times can increase or may initiate a bugcheck.

As part of disk operations to reclaim free space from thin LUNs, Windows 2012 Server can issue large numbers of the SCSI command 0x9E/0x12 (Service Action/Get LBA Status). This SCSI command results in what is called a “DESCRIBE_EXTENTS” I/O on the VNX Storage Processor (SP.) These commands are used as part of the Trim/Unmap process to see if each logical block address (LBA) that has been freed up on the host’s file system is allocated on the VNX thin LUN. The host would then issue Unmap SCSI commands to shrink the allocated space in the thin LUN, thus freeing up blocks that were no longer in use in the file system. RecoverPoint also issues these same SCSI commands when the Thin LUN Extender mechanism is enabled, which can cause similar performance issues. See knowledge base article KB174052 for more information about the RecoverPoint variation of this issue and how to prevent it.

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How to change the VNX weekly heartbeat date and time

Posted by on May 23, 2014 No comments

Changing the time for the weekly heartbeat

People with Clariion or VNX systems installed on site know that these arrays will email “home” (that’s EMC/you) once a week on a seemingly random date/time. Ok, once the day of the week and the time are set, each week the “I’m still alive” email will go out at that time. But what if you don’t want to have that email sent out at Thursday at 2:47AM and you want all of your arrays to send out that email on Saturday at noon sharp? You will need to adjust the parameters. I didn’t find a way to change the weekday, so I’m changing the time less than a day before it needs to run. So if I want it to run on Saturday at noon, I could run this script on Friday after noon. It will pick the next available day automatically.

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EMC World 2014: short week and too much to do

Posted by on May 2, 2014 No comments
EMC World 2014

It’s that time of the year again: EMC World

15 Thousand nerds gathering in Las Vegas for the yearly week of EMC propaganda. That’s what a lot of people might think it is anyway. It’s the 2014th edition… that doesn’t sound right. Ehm, oh well, you get my drift. Well, maybe it is nerd-week, but hey: every vendor who thinks they’re the best in something is doing this sort of events and besides that, it’s a great event to meet people you haven’t seen in a year or so.

Social networking in real life

Social networking, gathering knowledge of things to come, looking for solutions to challenges you already have in your normal day jobs, looking for insights in things on your wish list. Bacon, unicorns, hardware and a loooot of “software”, since that’s the trend since a few years. No matter how you explain it:

IT is in Las Vegas, baby!

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Which Hot Spare will be used for a failed drive? – part 2

Posted by on January 30, 2014 4 comments
Hard Drive

A while ago I talked about Hot Spares and how they are picked when a rebuild is necessary. It was almost 2 years ago and you can read it here.

Since then the rebuild / equalize technology has changed! Well, not for existing systems, but the new VNX family aka VNX2 does things a bit differently.

In the old days when a drive failed, a suitable Hot spare would kick in and the unprotected LUNs (regarding the failed drive) would be rebuild onto the Hot Spare. After a while, when the rebuild was done and the failed drive was replaced by a replacement drive, the data on the Hot spare would need to be copied to that new drive. This was called equalizing.

In the VNX2 (with MCx) this last step doesn’t exist anymore. So that means the Hot spare that was used to contain the rebuilt data is not longer a Hot Spare! It has become a regular drive! And that replacement drive will now be a new Hot Spare. When configuring a new VNX2 you’d see rules about Hot Spares and you simply don’t even need to configure Hot Spares anymore. Just make sure you have some unconfigured drives and you’re good. Your VNX2 will make sure they’re used as Hot Spares from then on.

If I remember correctly the DMX4 had a similar feature back in 2008, but it now flowed to the midrange platform as well.