In RA 9.0, interfaces are getting automatically set to disabled after manually enabling them. The Auto-Enable new interfaces option in the RA Application Settings may also automatically set to false, even after manually setting it to True.
RA will automatically set the auto-enable to false as well as disable all interfaces which are not licensed yet in RA when it encounters an exception pumping data.
This normally is one of these problems:
Invalid License (InvalidLicenseException)
Not enough room on the DSA (DataStorageApplianceAllocationException)
Not enough interface licenses (InterfaceLicenseLimitException)
Some issue causing an error with the data pump
There is also a general exception, when we fail to create an agent for some unknown reason.
(See this KB as a possible cause: Duplicate Interface error in PumpLog/New Interfaces auto disabled)
In each of these cases the exception is indicating that no matter what we won't be able to create any new agents, until the data problem is resolved. Since trying to create an agent and failing is very expensive when processing data, we temporarily disable interfaces not licensed and set the auto-enable to false. After 15 minutes we will attempt to create agents again and see if it works, though there is nothing that will set the auto-enable setting back to true (which we should probably fix).
Finally, with the RA 9.0 upgrade there is a defect (24930, fixed in SP1) that can cause this behavior. It can occur shortly after migration when we attempt to create an agent for a broadcast interface which does not have a router. Deleting the routers / interfaces from the harvester that the router is reporting to should resolve this problem.
Investigate the pump logs and look for some sort of error message.
Due to errors, disabling all existing interfaces that don't have agents.
Then resolve the problem with pumping data.
If it's a license problem give them a correct license.
If it's the broadcast interface problem then delete from harvester.routers & harvester.interfaces tables. Restart harvester service. This is resolved in 9.0.161, so alternatively you could just upgrade.
After fixing the issue and waiting 15 minutes, you should be able to change the Auto-Enable interaces setting back to true and have it stay true. Interfaces you enable in the enable interfaces page should also remain enabled.