Tag Archives: CML

Dell Compellent – ESXi HBA Queue Length

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This is a quick post that is more for my reference than for anything else. When I had the Compellent installed, Dell passed on a copy of the “Dell Compellent Storage Center Best Practices with vSphere 5.x” document (Dell P/N 680-041-020). One of the interesting points I noted was around modifying the queue depth, and where that should be done. As with any best practice document, there are going to be factors that may influence the outcomes of these activities in a positive or negative fashion. In other words, YMMV, but I found it useful. As always, test it before launching into production.

Firstly, set the HBA queue depth to 255 via the HBA BIOS. The thinking here is that the VMkernel driver module ultimately controls the HBA’s queue depth. Now, set the queue depth on the driver module. I use QLogic HBAs in my environment.

To find the correct driver name for the loaded module, run the following command.

esxcli system module list |grep qla

The output should be something like qla2xxx

Now run the following command.

esxcli system module parameters set -m qla2xxx -p "ql2xmaxqdepth=255 ql2xloginretrycount=60 qlport_down_retry=60"

Note that you can also set it via Disk.SchedNumReqOutstanding (DNSRO), where the default value is 32. Keep in mind that this setting is only enforced when more than one VM is active on the datastore. This is a global setting too, so if you’ve set the DNSRO value to 64, for example and you have two datastores in place, one with 4 VMs and one with 6 VMs, each VM will get 64 as the queue depth value. VMware recommend that this value be set to the same as the VMkernel module driver value.

You can also modify the queue depth in the Windows guest OS my modifying the registry settings of the OS.

In any case, go check out the document. It’s one of the more useful white papers I’ve seen from a vendor in some time.

Dell Compellent – Storage provisioning with CompCU.jar

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I covered getting started with the CompCU.jar tool here. This post is a quick one that covers provisioning storage on the Compellent and then presenting it to hosts. In this example, I create a 400GB volume named Test_Volume1 and place it in the iLAB_Gold2 folder.

E:\CU060301_002A>java -jar CompCU.jar -defaultname saved_default.cli -c "volume create -name "Test_Volume1" -size 400g -folder iLAB_Gold2"
Compellent Command Utility (CompCU) 6.3.1.2
=================================================================================================
User Name: Admin
Host/IP Address: 192.168.0.10
Single Command: volume create -name Test_Volume1 -size 400g -folder iLAB_Gold2
=================================================================================================
Connecting to Storage Center: 192.168.0.10 with user: Admin
java.lang.IllegalStateException: TrustManagerFactoryImpl is not initialized
Running Command: volume create -name Test_Volume1 -size 400g -folder iLAB_Gold2
Creating Volume using StorageType 1: storagetype='Assigned-Redundant-4096', redundancy=Redundant, pagesize=4096, diskfolder=Assigned.
Successfully created Volume 'Test_Volume1'
Successfully finished running Compellent Command Utility (CompCU) application.

Here’s what it looks like now.

vol2

Notice that Test_Volume1 has been created but it inactive – it needs to be mapped to a server before it can be brought online.

E:\CU060301_002A>java -jar CompCU.jar -defaultname saved_default.cli -c "volume map -name 'Test_Volume1' -server 'iLAB_Gold2'"
Compellent Command Utility (CompCU) 6.3.1.2
=================================================================================================
User Name: Admin
Host/IP Address: 192.168.0.10
Single Command: volume map -name 'Test_Volume1' -server 'iLAB_Gold2'
=================================================================================================
Connecting to Storage Center: 192.168.0.10 with user: Admin
java.lang.IllegalStateException: TrustManagerFactoryImpl is not initialized
Running Command: volume map -name 'Test_Volume1' -server 'iLAB_Gold2'
Successfully mapped Volume 'Test_Volume1' to Server 'iLAB_Gold2'
Successfully finished running Compellent Command Utility (CompCU) application.

Wouldn’t it make more sense to create and map the volume at the same time? Yes, yes it would. Here’s another example where I present the volume to a folder of servers.

E:\CU060301_002A>java -jar CompCU.jar -defaultname saved_default.cli -c "volume create -name "Test_Volume2" -size 400g -folder iLAB_Gold2 -server iLAB_Gold2"
Compellent Command Utility (CompCU) 6.3.1.2
=================================================================================================
User Name: Admin
Host/IP Address: 192.168.0.10
Single Command: volume create -name Test_Volume2 -size 400g -folder iLAB_Gold2 -server iLAB_Gold2
=================================================================================================
Connecting to Storage Center: 192.168.0.10 with user: Admin
java.lang.IllegalStateException: TrustManagerFactoryImpl is not initialized
Running Command: volume create -name Test_Volume2 -size 400g -folder iLAB_Gold2 -server iLAB_Gold2
Creating Volume using StorageType 1: storagetype='Assigned-Redundant-4096', redundancy=Redundant, pagesize=4096, diskfolder=Assigned.
Successfully mapped Volume 'Test_Volume2' to Server 'iLAB_Gold2'
Successfully created Volume 'Test_Volume2', mapped it to Server 'iLAB_Gold2' on Controller 'SN 22641'
Successfully finished running Compellent Command Utility (CompCU) application.

Note that these commands don’t specify replays. If you want replays configured you should use the -replayprofile option or manually create replays with the replay create command.