Arcgis 11.2 Layers disappear from the service

[Dvirus]

New Arcgis 11.2 Enterprise Deployed on one machine with:
Portal for arcgis
Arcgis server
Web adaptor for portal
Web adaptor for arcgis
Db on sperate AWS-RDS instance.
It's not builder installation.

Sometimes Some layers that published under the same service simply disappear.
All layers in the service are from the same data source
Turning the service off and on usually returns it to normal.

Any suggestions?

[TimoT]

Anything in your server logs? Perhaps something along the lines of 'Failed to construct instance of service' or something about DynamicMappingHost?

I've seen a similar behavior when the shared instance pool is overloaded or a complex service does not have enough dedicated instances allocated to it. You could theoretically be experiencing the opposite where you have overloaded your server machine with too many instances and your system can not fire up any new instances.

Either way, I'd start by checking the ArcGIS Server logs that your AWS-RDS is registered to.

If it is instance related, here are some informational resources you can look at:

• Configure service instance settings—ArcGIS Server | Documentation for ArcGIS Enterprise
• Introducing shared instances in ArcGIS Server (esri.com)

Timo