You just can't beat free monitoring tools, particularly when the tools are useful. One such tool, the SolarWinds VM Monitor, watches an ESX server and visually alerts you in the event of a problem. Even when there isn't a problem, you still get a visual status. Scott Lowe provides information about this tool.
It used to be that a picture was worth a thousand words; however, when it comes to the free SolarWinds VM Monitor tool, the picture that is provided is worth a whole lot more. Although this teaser product is limited to monitoring a single ESX server, the output is incredibly useful and provides true at-a-glance status information about the health of your ESX server.
The product installation couldn't be easier. Simply install SolarWinds VM Monitor, provide the IP address or name of your ESX server as well as that server's read-only SNMP string, and output like you see below is generated.
In this capture from one of our live ESX servers, you can see that this machine has nine of 10 installed virtual machines powered on with one VM in a critical state due to CPU running at full-throttle. You'll notice that it's only the virtual machine's CPU that's running at 100% though. The ESX server CPU is still running at only 16% capacity. You also get to see how much RAM is actually being used by both individual virtual machines and by the ESX server (and all running VMs) in total. With the RAM in FILER_VM running at only 27% utilized, it might be possible to reduce the amount of RAM dedicated to this virtual machine. A tool such as SolarWinds VM Monitor aggregates information in a way that is useful in decision making regarding resource utilization. (Just for the record, I do know why the FILER_VM virtual machine has a pegged CPU, and it's normal for the time of day and the week that I took this screenshot and is not user-impacting.)
I said earlier that this is a teaser product because, while useful, it has some very obvious limitations. Most notably, the product monitors only a single ESX server. For each virtual machine, only a very few high-level performance statistics are monitored. This is one of the "gateway tools" that SolarWinds gives away for free to entice you to buy its Orion full-fledged monitoring product.
To install and use SolarWinds VM Monitor, follow these steps:
- Using a tool such as PuTTY, SSH to your ESX server and log in as the root user.
- Allow SNMP traffic to traverse the firewall: esxcfg-firewall -e snmpd.
- Enable ESX's SNMP service: service snmpd start.
- Download the SolarWinds VM Monitor.
- Extract the contents of the downloaded ZIP file.
- Double-click SolarWinds-VM-Monitor-v1.0.exe.
- Run through the installation.
- When prompted, provide the name or IP address of your ESX server along with the public SNMP string from your ESX server. The default string is public. If your public string is different, you can find it on your ESX server in the /etc/snmp/snmpd.conf file on the line that starts with rocommunity.