This thread discusses making the change for Windows vCenter server.
Customize email alarm subject lines in vCenter Server 5.1.0?
The change on Windows vCenter is easy, just modify this file - ProgramData\VMware\vCenterServer\cfg\vmware-vpx\locale\en\stask.vmsg
I would like to know how/where to make the change on the vCenter appliance (using 6.5, but might need to install a 6.0 appliance also)
Desired subject - [VMware vCenter - server.contoso.local] alarm.HostMemoryUsageAlarm changed status from Yellow to Green
Current emails:
Subject:
[VMware vCenter - Alarm alarm.HostMemoryUsageAlarm] alarm.HostMemoryUsageAlarm changed status from Yellow to Green
Body:
Target: server.contoso.local
Previous Status: Yellow
New Status: Green
Alarm Definition:
([Yellow metric Is above 90%; Red metric Is above 95%])
Current values for metric/state:
Metric Memory Usage = 91%
Description:
Alarm 'Host memory usage' on server.contoso.local changed from Yellow to Green
