One or more DSAs does not start and reports 'inconsistent,' or 'Error 13: The data is invalid', for example:
There may be PID files left over from a previous run that still exist after an unexpected server restart.
Go to this location on the Directory Server...
...and delete all the files you see in there.
Attempt to start your DSAs. This should solve the problem and create a new PID files..
Normally, when a DSA shuts down it removes the PID files and creates a new one upon start up.
If you are using CA Directory r12.0.18 or higher, you can resolve the issue by running the following command, from within the dxhome location ($DXHOME or %DXHOME%): dxserver forcestart <dsaname>
You can verify the CA Directory version by running the following command: dxserver version