Modify VMware vCenter 5.5 Alarm Notifications using PowerCLI

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.

vCloud Director Resources Allocation

In vCloud Director (vCD) 5.x, you may have seen this error or heard a complaint from customer that when a new VM deployed, powering it on caused this error:

“The operation could not be performed, because there are insufficient memory resources” also “The available Memory resources in the parent resource pool are insufficient for the operation.”

This error might seem natural and you might suspect to the allocations of VDC but if the organization VDC is created using Allocation Pool model, the story is different. You sum up the memory assigned to all VMs and the total amount might be less than allocated amount in VDC. Most likely, it is because of the amount set in “Memory resources guaranteed” field of VDC. In fact, by default this is set to 20% and this value is the minimum number you can set. Since VMware reserves this amount of Memory, you should add it to the total amount (sum of all VMs) of RAM calculated before and then compare it to “Memory allocation”  that should be less or you will encounter the mentioned error message.


So, to prevent this error, you must be more generous in assigning “Memory allocated” value of VDC because reducing “Memory resources guaranteed” less than 20% is not possible!

Quick Stats on Host not up-to-date

In VMware vSphere client (native and web client), sometimes you get this message in Summary tab of a host: “Configuration Issues: Quick stats on Host ‘xyz’ is not up-to-date”
Most of the times this message disappears after a while but sometimes it bothers for a long time. In those cases, a quick ‘Reconfigure for vSphere HA’ may clear the message.

VMware vSphere ESXi 5.5 and Heartbleed

Well, bad news for those who upgraded to version 5.5 is that: apparently VMware ESXi 5.5 is one of few VMware products that is being affected by heartbleed vulnerability! because of using OpenSSL 1.0.1. As VMware confirmed here, they are working on it to give out a patch; although because ESXi’s are usually deployed in a private, protected environment; the effects of this vulnerability is mitigated. Still, we should monitor VMware website for latest patches.

Upgrade Distributed vSwitch from 5.1 to 5.5

When you upgrade your VMware environment to version 5.5. remember to upgrade your distributed vSwitch as well; it will not be done automatically. In this way, you can utilize new features in dvSwitch 5.5, including:

The upgrade process is fairly easy and the good thing is that according to VMware documentation, it is non-disruptive which means there is no outage and no host and VM will get down or experience issues. Find your distributed vSwitch either in vSphere Client or Web client, right click and do upgrade.