Today I had a situation where after a hardware crash my GlassFish Server did not work correctly. Specially the timer service did no longer work. The server log shows a lot of errors about
...EJB Timer Service not available
In the easiest case the reason why the timer service did not start are old db.lck files.
You can check this by stopping the server and then look for any lock files in the domain folder
../lib/databases/ejbtimer/
After removing the files
dbex.lck db.lck
you can restart the server and every thing should work again.
See also the following thread if this did not work for you: