Forum Discussion
Limit what data in Log Analytics to be passed on to Sentinel?
We have been using Sentinel in conjunction with Azure Log Analytics for quite some time to ingest selected security logs (AD, DNS, Windows Security etc.) from VM-agents in our server environment. Last week we upgraded the workspace to enable the newly released "Azure Monitor for VMs" and also installed the Service Map agents on our VMS. This resulted in a huge increase of data ingested into Sentinel (5x, see attached image) due to VM performance metrics and network traffic logs from the the Service Map now being ingested into Sentinel, that I have no interest in having there.
How can I choose/filter what logs from a Log Analytics Workspace that is forwarded to Azure Sentinel?
Magnus Tjerneld You cannot state which information stored in a Log Analytics workspace is available to Azure Sentinel. It is an all or nothing proposition.
You can control what data gets ingested from the VMs by clicking on the "Windows, Linux, and other sources" link on the Overview page and from there go to the "Data" section. This will show you what logs you are ingesting as well as severity for each log. You can go through the list and see if you can trim down some of the information being imported.
Ok; that's too bad. I dug a little deeper into the increased log volumes and realized that the bulk of the records/sources are not visible under Data Connections.
Previously; before we upgraded the Workspace to onboard "Azure Monitor for VM:s" I was manually pulling a number of selected perfmon counters (CPU, RAM and so on). I did this at a 5 min interval to give me an overview without causing too much data in OMS. But after enabling Azure Monitor for VM:s, a huge number of new counters has been enabled and the resolution is much higher. Over the last 24h I've recieved ~300k datapoints for the 4 VMs I'm monitoring:
Computer 11,499 LogicalDisk 205,315 Memory 5,744 Processor 5,744 Network 14,360
None of these namespaces are visible under Data Sources in Log Analytics.
It would be great to be able to lower the resolution/interval, but I can't seem to find anywhere to limit the interval on these logs?
I realize that this is now more of an "Azure Monitor for VM:s" question than a Sentinel question.Magnus Tjerneld Did you check under the "Windows Performance Counters" in the "Data" section?
