Very recently Microsoft added Azure diagnostic extension for Linux VM in Azure. Working with Operational Insight in OMS you will probably want to have that data there. How to do it? First of all, enable diagnostics for Linux virtual machine you have in Azure.
After that login to your Azure portal and add Storage account like data in Operational Insights
After some time you should see syslog data in your search and added 1 storage account in settings pane in OMC. Cheers