mainesysadmin.com

This vague message turned into a nightmare for myself this past Sunday.  I was able to get the problem fixed with minimal downtime as the issue only came up during a Sunday maint. window (ironic).

I had patched my ESX hosts to Update2 (patched version) and started receiving the error “VMware HA Agent has an error” in my virtual infrastructure client.  First step is to make sure you’re running a compliant version of Virtual Center with your ESX.  Ok, Check.

Next check your host files in each esx host located here:  /etc/hosts

You should see the default line of 127.0.0.1 for localhost, below there needs to be at least one linewith the host your working on.

192.168.1.103     esx9.yourdomain.com     esx9

Over the past 3 years I’ve seen conflicting guidance over the configuration of the host files .  In 3.0.2 I was required to enter all my hosts in each host file, but now that seems to be resolved and only requires the local details of the host you’re working with.  In short make sure that you can ping your hosts from each host with the FQDN and/or friendly name and you should be all good there.

The next steps were found on some vmtn.net postings, and I lost the URL amongst all my troubleshooting but I saved the resolution.  For myself I found the following steps helpful in resolving the problem….

The problem in my situation was specifically around the Virtual Center agents and conflicting versions.

• Check the vpxa version on your host:  rpm -qa |grep vpxa
• That will give you the current version of vpxa that you’re running. eg:  VMware-vpxa-2.5.0-104215
• Stop the VMware mgmt service:  service vmware-mgmt stop
• Stop the vpx agent:  /etc/init.d/vmware-vpxa stop
• The vpx agent error can be ignored (warning: /etc/vmware/vpxa.cfg saved as /etc/vmware/vpxa.cfg.rpmsave)
• Remember your vpx version from the first step and use it here to remove the vpx agent.
• rpm -e VMware-vpxa-2.5.0-104215
• Switch over to your Virtual Center client and remove the host you just modified (guest vms will remain)
• Reboot the host (vm’s will go down)
• After boot reconnect the host to VC and the latest vpx agent will be intstalled.
• Enable HA and the error should disappear.

Luckily my event occurred on a Sunday.  This was the first time that the guest vm’s experienced unplanned downtime without being able to vmotion in 3 years.  Be careful with those VMware patches!

Scott featured a nice write up comparison of ESX nic utilization and vSwitch configuration the other day.  The article is specifically around the Guest VM vSwitch and compares the differences between Link Aggregation and the opposite.  It’s a useful reminder of the load balancing characterists of the different settings in the vSwitch.

This was a two part series on his webpage:

Part 2: http://blog.scottlowe.org/2008/10/08/more-on-vmware-esx-nic-utilization/

Part 1: http://blog.scottlowe.org/2008/07/16/understanding-nic-utilization-in-vmware-esx/

In the last year we had a physical server’s O/S have a severe blue screen error which required the server to be rebuilt.  This server was a critical server for our operation and the downtime was not easy.  In order to prevent that from happening in the future we decided that server would be a better fit in the virtual infrastructure because of the High Availability offered by Vmotion.  The only problem is this server requires a USB license dongle.  Everyone knows that you don’t have a USB port to plug into when running VI3, so what do you do?

Keyspan USB server (USB over IP)

This specific USB server allows you to choose which USB port(s) you want to dedicate to each server.  Some USB servers do not allow you to dedicate each port to a different server.

What a breeze to setup as well.  After you mount the device, give it power and ethernet…Just install the Keyspan software.  The software client will find the USB server automatically.  Than you need to edit the config to dedicate the USB device to that VM and you’re ready for action.

Now you can reboot and vmotion to your heart’s desire and not lose connectivity to your USB license dongle.  Great little trick if you’re as dedicated to virtualization as we are!

I landed in San Francisco yesterday at around 1:3o pm. Another excellent experience with United; 6 hours and on time from Boston. I rented a car and found my way to the hotel pretty easily. Most of the roads feel pretty difficult to maneuver. The Marriot I’m staying at is around the corner from the Moscone center which is great.

Today I was able to register for the event which included a free laptop bag and t-shirt. I started my day with an 8am lab dealing with DR and multiple sites. The lab felt slightly unorganized but it was the first one of the day and also first of the conference. There were multiple typos in the lab manual. If someone had never used Virtual Center before I can see it useful. I followed this lab with one on Security and Hardening ESX. I actually took this lab last year as well and I’ve found that this lab might not have changed at all and if it did is was probably slightly. I’m not sure if that was good or bad. I thought the lab would have been slightly more updated.

As promised I remembered to dig into my virtual center event logs to pull out the error message that I received after upgrading my 3 esx servers.  “An error occurred during configuration of the HA Agent on the host.” “hostmisconfigured : failed to resolve hostname/ip using short hostname yourdomain.”Simply add your hostnames and ip’s to /etc/hosts

update the following file on your new esx server with the hostname of the new server

/etc/hosts

restart the following service:

service mgmt-vmware restart