Requirements for Maintenance Mode

[kresejg85]

Hi,

I wanted to understand when maintenance mode is required prior to shutdown. I have a simple setup with one host running about a dozen vms. Is it necessary for me to put the server into maintenance mode every time I shut the server down? Or is it really only required with a multi-host setup where you are migrating VMs, etc? I'm having a hard time finding info for a single host.

Thanks!

[daphnissov]

You should always use maintenance mode when you want to reboot or shutdown a host.

[NathanosBlightc]

1. It's not a required action to put the ESXi host in maintenance mode always in each situation, before the shutdown operation, however it's recommended. you should know this important point: Sometimes you cannot shut-down the host for any possible reason, like hardware issues. For example, you saw a warning in the SD memory (ESXi is installed in there) while you need to replace another hardware device in the physical server, So you don't want to accept the risk of boot failure after a reboot/shutdown operation. Then you can put the ESXi host in the maintenance mode, instead of shut-down. (Of course, until you replace that SD memory and then do the shutdown actually )

2. For some other management actions, you always need to put the ESXi host in the maintenance mode, regardless of requiring to reboot or not. Like installing a hardware driver (vib file), related to a hardware device and then you need to reboot it! or uninstalling that vib and there may be no requirement for reboot action. So you should always care about when and in which situations you really need to activate the maintenance mode.

[kresejg85]

Thank you! That's kind of what I had gathered online, but I couldn't find any actual solid information about it.

[IRIX201110141]

As already told from the others.... MM is not a requirement. The MM would prevent the start of VMs.. thats it.

• If you have a single host and would like to use the VM Autostart feature
• If you would like to see a host perform an reboot and becomes active in an HA cluster again

These are all actions where no MM is needed/allowed or usefull.

Regards,
Joerg

[kresejg85 · Accepted solution]

Thanks Everyone, putting both responses here that have been helpful and marking this as correct:

1. It's not a required action to put the ESXi host in maintenance mode always in each situation, before the shutdown operation, however it's recommended. you should know this important point: Sometimes you cannot shut-down the host for any possible reason, like hardware issues. For example, you saw a warning in the SD memory (ESXi is installed in there) while you need to replace another hardware device in the physical server, So you don't want to accept the risk of boot failure after a reboot/shutdown operation. Then you can put the ESXi host in the maintenance mode, instead of shut-down. (Of course, until you replace that SD memory and then do the shutdown actually )

2. For some other management actions, you always need to put the ESXi host in the maintenance mode, regardless of requiring to reboot or not. Like installing a hardware driver (vib file), related to a hardware device and then you need to reboot it! or uninstalling that vib and there may be no requirement for reboot action. So you should always care about when and in which situations you really need to activate the maintenance mode.

As already told from the others.... MM is not a requirement. The MM would prevent the start of VMs.. thats it.

• If you have a single host and would like to use the VM Autostart feature
• If you would like to see a host perform an reboot and becomes active in an HA cluster again

These are all actions where no MM is needed/allowed or usefull.

[NathanosBlightc]

Still remember you cannot mention maintenance mode is not useful, It's absolutely not correct! You should know in which situation you should activate it and when it's required ... Actually you shall not compare it with the reboot operation ...