VM-Aware

I recently came across a problem whereby a Rescan SAN was taking an absolute age, like 15 minutes from the VI Client. Now I love the VI Client, but sometimes it just doesn’t give you enough information when it is doing things. To be fair most of the time the verbose information is simply not needed, but when things go wrong it is a god send.

In comes the Service Console command line, more specifically the esxcfg-rescan and esxcfg-mpath commands. (more…)

I don’t know if you are like me and feel initially a little bit nervous about messages that contain phrases like “there may be some interruption to I/O”.  This is the type of message that you get when you make any changes in the Zoning Admin area of a Brocade switch when you’ve made changes to an effective config.

I recently added a lot of new zones to a customer fabric as they were implementing DataCore.  With this brought lots of new WorldWide Names and some of which needed to be kept completely separate from the ESX hosts.  I went ahead and created all my zones and saved the config using the Save Config Only option.  Nothing happens at this point as it isn’t actually updating the live config just saving the changes.

If you want to apply the changes to make them live then you’ll need to use the Enable Config option and with that brings the dialog to choose the config to apply.  Choose the correct config and then you are warned of the possible interruption to I/O.  This is where I was slightly perturbed.

I can confirm that VMware ESX 3.0.2 & 3.5 does handle any interruption (which appeared to be either minimal or non-existent) seamlessly.

That said, if you can get your customer to agree to do it out of hours this is obviously preferable, however the customer I was at is a 24/7 operation.  One other thing I can’t vouch for as yet is how well Windows nodes handle the config update so progress with care here.

Anybody using Brocade Fibre Switches on a regular basis will notice that sometimes the web interface can sometimes be, shall we say funky!

It sometimes show defragmented fabric in the web browser, but there is no reason for it etc.

Here’s an overview of some useful commands that you can execute from the Telnet command line: (more…)