How to find dead iSCSI/FC paths in vSphere ESX 4.x ?

Have you been receiving Storage Disconnects alarms from your vCenter quite often? Here are some quick commands to see if there are any dead paths.

esxcfg-mpath -l | grep -i dead

Following command does the same thing but lists extra information

esxcfg-mpath -b | grep -i dead

If resulting output contains dead paths and you want to be sure that it's not from some earlier known issues in your environment, you can run the following command to rescan all your targets

esxcfg-rescan vmhbaXX , where XX is the last two digits your HBA under Storage Adapters in vCenter.


Run esxcfg-mpath -l | grep -i dead or esxcfg-mpath -b | grep -i dead again and see if it results in any dead paths, if it does then there may be some serious connectivity or storage issues with your SAN. 

Use vmkernel ping to verify you can ping all your iSCSI targets.

vmkping 192.168.x.x, where 192.168.x.x is the IP of target IP of your SAN.

For Fiber Channel, make sure your SAN software sees all FC HBAs as registered and that are no zoning issues.

Free VMware Utilities

This site has some pretty cool VMware tools that come in very handy for daily VMware operations.

http://www.phdvirtual.com/utilities/

Check it out!

Daily Exchange Health Checklist

Here a few daily tasks that I perform each morning after a cup of coffee to ensure that my Exchange environment is running smoothly. This has proven very helpful in preventing many issues with my Exchange servers. I came up with the list while managing Exchange 2000/2003 environments but it still helps me with Exchange 2007 as well. Hope it will help others out there.

• Check event viewer for warnings/errors on all Exchange Servers
• Check for database fragmentation
• Check postmaster mailbox for NDRs
• Check exchange statistics
• Check bad mail folder for trends
• Check OS status on Exchange boxes
• Check if plenty of disk space is available on all BE & FE servers
• Check for cluster failover in cluster admin
• Check message load in the queue viewer
• Check OS/Exchange Services
• Check results of real-time performance monitoring for all servers
• Review event, performance vs. anti-virus logs
• Track message for security project
• Verify integrity of Exchange Store

Fiber Connector Types

Large portion of my datacenter infrastructure currently consist of clusters using fiber storage on EMC SANs and Brocade fiber switches. There are also uplinks to data switches from core routers and all these different fiber connections use many different types of fiber connectors that at times confuse the hell out me. I am no cabling expert so I thought it would be nice if I can put it all together on piece of paper as a reference. Finally, I found this image in a document and thought would be nice to share it with all. It explains all major types of fiber connector types used in today's datacenters.  Hope this will help someone else out there trying to go nuts between MT-RJ and LC-LC or ST-LC fiber connections.