some of Azure virtual machine custom performance counters are not being collected in log analytics

1
votes

we want to collect some of the performance counters from the VMs and then query them in the Azure Logs. The basic Performance Counters are enabled but some of them were missing, so we used the custom Performance counters to add the rest. Most important is the \LogicalDisk(*)\% Used Space, regarding: https://docs.microsoft.com/en-us/azure/azure-monitor/platform/data-sources-performance-counters

The Perf were added in the advanced Settings of the WorkSpace and in the Diagnostic settings of the VMs, but the new perfs (here % Used Space) is not being collected.

It's been 3 days since I added it but still when I query the current collected counters it gives me only:

Free Megabytes
Avg. Disk sec/Write Disk Writes/sec Disk Bytes/sec
Avg. Disk sec/Transfer
Disk Reads/sec
Disk Write Bytes/sec
Avg. Disk sec/Read
Disk Transfers/sec
Disk Read Bytes/sec % Free Space

1
azureazure-log-analyticsazure-performancecounters

1 Answers

1
votes

Usually after you configure the perf counter you should see the data flowing in 30 minutes.

Few Clarifications needed ..

1) Is your VM Windows or Linux ?

If i know properly \LogicalDisk(*)\% Used Space is the Linux performance counter. Windows does not have the perf counter by the name in the Logical Disk. If it is a Linux machine then you should be able to see that counter under Linux Performance Counter tab in Log Analytics.

2) If it is correctly configured for appropriate machine OS ?

Check if the machine is showing a HeartBeat in Log analytics and agent is healthy. If not healthy if not follow these steps for troubleshooting.

https://docs.microsoft.com/en-us/azure/azure-monitor/platform/agent-windows-troubleshoot

3) Also ensure that is is properly saved. Usually the Azure portal save option is usually deceiving once you select the counters and hit okay. You need to hit the save option in the Log analytics data sources tab of the portal.