When I added an extra SCSI card to my ESX 3.5 test system I could not get it to reconnect again with VirtualCenter. After a close inspection I noticed that vmnic0 did not exist anymore(esxcfg-nics -l), it got renamed to vmnic1. Because of that my vSwitch0 did not have a NIC linked to it anymore. I linked the new vmnic1 to my vSwitch0(esxcfg-vswitch vSwitch0 -L vmnic1) and everything was up and running again. I’m glad this didn’t happen in a production environment with several vSwitches and portgroups, than again it is possible to rename them again by manually editing the /etc/vmware/esx.conf file. There’s a knowledge base article on this behavior on the VMware support site, I noticed it a couple of weeks ago an now I witnessed it. Definitely not the first place I would normally look. I hope VMware can fix this glitch, although I can fully understand why this happens.
3.0.x
Service Console redundancy
The last couple of weeks more blogs and topics appeared around the warning VirtualCenter gives when there’s no service console redundancy. Several people posted about a workaround to clear this warning. The workaround is very easy: temporarily assign an additional nic to the service console vSwitch and reconfigure your HA. Notice that I used ” workaround” cause I definitely don’t see this as a solution for the problem. With the current technology there’s not much reason not to have a redundant service console in my opinion, especially when you are using HA. I know a nic hardly ever breaks but in this case probably more than 8 VM’s rely on this nic, the physical switch and the network cable it’s attached to. [Read more…] about Service Console redundancy
Migration will cause the virtual machine’s configuration to be modified
When live migrating from ESX 3.0.2 to ESX 3.5 VMware gives an error:”Migration will cause the virtual machine’s configuration to be modified, to preserve the CPU feature requirements for its guest OS.” This error indicates that the .vmx file is about to be changed.
[Read more…] about Migration will cause the virtual machine’s configuration to be modified
New version of the High Availability best practices and advanced features PDF
VMware updated the PDF about High Availability with extra advanced options for ESX 3.5/VC 2.5. They’ve also added recommendations for additional Service Console redundancy. Until now I’ve always worked with a two nic based Service Console instead of a second Service Console on the VMKernel network, will test with the second Service Console to see if it works like expected… cause according to the VMware recommendations it saves up till 40 seconds in recovery time.
[Read more…] about New version of the High Availability best practices and advanced features PDF
Port range and esxcfg-firewall
An often made mistake when trying to open up or close a port range with the ESX(3.0.2 and 3.5) firewall is using the dash(-) as a divider. Using the dash unfortunately does not always result in an error. To open up or close a port range you should use a collon(:) as a divider:
esxcfg-firewall –openport 6000:6010,tcp,in,test