Friday, 20 April 2012

ESXi 5 EqualLogic best practices.

If you are using Raw Device Mapped (RDM) disks in your VM's, make sure the pathing for that is changed to RR and IOPs 3 as well.  (MEM would also set this connections up properly as well)
Other common tweaks are disable DelayedACK  (its in the iSCSI initiator properties) and disable Large Receive Offload (LRO)
Within VMware, the following command will query the current LRO value.

# esxcfg-advcfg -g /Net/TcpipDefLROEnabled
To set the LRO value to zero (disabled):

# esxcfg-advcfg -s 0 /Net/TcpipDefLROEnabled
NOTE: a server reboot is required.

Info on changing LRO in the Guest network.

ESXI v5.0 should also have the Login Timeout changed to 60 seconds.  (default is 5).  However, you have to be at build 514841 or better.  
See VMware KB 2007680

One more common enhancement that gets missed often is creating a virtualized SCSI adapter for each VMDK (or RDM) in each VM.  (Up to 4x controllers)     If you look in the VM settings, each VMDK/RDM shows a "Virtual node"  
It will say 0:0, for first drive, then 0:1, 0:2, etc...   Shutdown the VM, change the other VMDK/RDMs from 0:1 to 1:0, then 0:2 to 2:0 and so on.   This will tell ESX to create new SCSI controllers for each disk.  Really helps with Exchange/SQL/Sharepoint.   Things that have databases and logs or fileservers that have multiple VMDKs/RDMs
*** Script to change EQL volumes to RR and set the IOPs to 3 in ESXi v5.0. ****
This is a script you can run to set all EQL volumes to Round Robin and set the IOPs value to 3.  (Datastores and RDMs)

#esxcli storage nmp satp set --default-psp=VMW_PSP_RR --satp=VMW_SATP_EQL ; for i in `esxcli storage nmp device list | grep EQLOGIC|awk '{print $7}'|sed 's/(//g'|sed 's/)//g'` ; do esxcli storage nmp device set -d $i --psp=VMW_PSP_RR ; esxcli storage nmp psp roundrobin deviceconfig set -d $i -I 3 -t iops ; done
After you run the script you should verify that the changes took effect.

#esxcli storage nmp device list

Thursday, 12 April 2012

Equallogic ASM/ME - Replication partner Not Available

ASM/ME reports Replication Partner Not Available. Even though manual replication works.

Issue was caused by the inability to access the VSS-CONTROL LUN on the replication partner. In my case the vssadmin username and password where correctly specified but the iSCSI initiator refused the login to the VSS LUN. The workaround is to set the VSS access at the group level to unrestricted while Dell investigate.

UPDATE. - Workaround from Dell PS.

Highlight the VSS-Control Volume and click connect you get an Advance button, Click it and you will get a pop up window and you should see your chap credentials there.
Enter you chap Credentials on both the hosts and that should resolve the issue.

Wednesday, 4 April 2012

Optimal iSCSI NIC settings

This can help eliminate TCP retransmits between EQL and the host.Find the 2x iSCSI NICs in the registry, only change this for NICs connecting to iSCSI storage.


Create two new DWORDS

TcpAckFrequency = 1
TcpDelAckTicks = 0

Restart the server.

Tuesday, 3 April 2012

Dell Life cycle controller crashes with Hardware Exeception

When you press F10 to access the Dell Life Cycle controller it crashes with this error.

!!!! x64 exception type - 00000000000000000000000D !!!!

This happened to me after using the life cycle controller to update all the firmware within the server.

The solution