Dell Equallogic PS5500e iSCSI SAN

The PS5500e provides 24TB of RAID 50 storage.

In this implementation, the PS5500 is providing storage for a cluster of nine Vmware ESX servers.

The ESX server cluster consists of nine Dell blades with dual quad-core CPU’s and 32Gig of RAM.

PS-5500e chassis - ready for drives

PS-5500e loaded with 48 1TB drives

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After the chassis is installed in the rack, the drives load from the top of the unit.

It takes a few minutes to unpack 48 drives and install them in the chassis.

It’s pretty impressive looking once all of the drives installed.

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ESX boot hangs at “restoring S/W iscsi volumes”

I ran into this problem last week after installing two new ESX hosts connected to via iSCSI to a Dell/Equallogic SAN.

After loading ESX and performing the iSCSI target configuration, I rebooted one of the hosts.  The boot process hung at “restoring S/W iscsi volumes”.  Eventually I became impatient and hit the power button only to have the same thing happen again after the hard reset.

This time I waited.  After about ten minutes the host continued the boot process and everything was normal.  Since I could see my iSCSI targets,  I continued with the cluster configuration in VCenter, converted a physical machine to a virtual guest and encountered no other issues.  Another reboot of one of the hosts revealed the problem still existed.

After parsing through /var/logs/vmware/vmkernel I found the following:

Feb 26 07:48:56 esx1 vmkernel: 0:00:04:54.761 cpu15:1089)<3>iSCSI: session 0xc203f90 login failed to authenticate with target iqn.2001-05.com.equallogic:6-8a0900-867555003-26300002be349a59-vss-control

During setup of the Equallogic, it will prompt for chap authentication credentials for the iSCSI targets.  Normally, I limit access to the targets by ip address.  However, the CHAP credentials are used for the vss-control iSCSI target.

If you have Windows hosts directly accessing the SAN, you need the vss-control target.  In my case, ESX doesn’t require vss-control because all of my volumes are VMFS.  Since VMware sees vss-control as a target it tries to connect to it.

There is a process you can go through to tell VMware not to attempt a connection to vss-control.  The simpler method is to use the VI client to add CHAP credentials to the iSCSI software adapter.  Click on Properties>Chap Authentication and enter the same CHAP user name and password that you input during the Equallogic setup process.  After that change, the ESX boot process now takes about two minutes.

iSCSI Software Adapter Properties