Configuring or modifying alarm notifications on vCenter can be time consuming because there are more than 80 pre-defined alarms (in vCenter 5.5) which need to be modified; and the point is that it’s not possible to apply a single change to all of them or a group of them at once. Via GUI (web client or native) alarms should be modified one by one. So, imagine that you want to add an email as recipient of some alarms, let’s say the ones which send email notification when status is changed from Yellow to Red and Yellow to Green. It’s difficult to go through all the alarms, find them and apply your changes. This kind of change is very common when a new administrator is added to the team or someone leaves.
It is one of the situations where using PowerCLI is really beneficial. You can customize and group the alarms as you want, change the variables whenever needed and run the script using PowerCLI. I found this template by Lauren Malhoit very useful but it was not compatible with vSphere 5.5. I modified the script for vSphere vCenter 5.5 and you can download it here. Using this script is easy by modifying email addresses and you can also change the groups (I mean for example adding to YRYG alarms) as you desired.