Are you using FileMaker Pro or FileMaker Server Advanced to host your database?
Could it be, if using FileMaker Pro, that there are already 5 web users logged on? (5 is the maximum number permitted for IWP.)
Oops, using FMS 12. Edited original posting. Also added statement about our backup schedule (hourly, on the hour).
Have you noticed any correlation between the back up schedule and the times the DB shows as unavailable?
Does your hourly backup schedule verify the backup copy?
Well, that is why I mentioned it: it does seem to coincide pretty closely with the backup schedule. Except that it sticks in my mind I have seen the 'unavailable' error at the mid-hour mark as well, and we don't have a backup running at that time. But I am not 100% sure.
Yes, our backup does a verify.
I strongly recommend against enabling verify for hourly backups. This can put an excessive load on fileMaker server that can affect server performance.
What we do, is schedule backups every two hours that are unverified. Then a separate schedule does a verified back up one each day late at night when no one (in our case) is accessing the database.
Thanks for the heads up on that. I will pass the idea around and see about putting that into place.
I found a reference to a possible bug in FMS12. It was in a comment from 'Mark' on www.briandunning.com. I found it in the comments attached to the detail page for the FileMaker "Error 802" (down at the bottom, 5/22). Ah heck, simpler just to post what he said:
This is also a bug in the version 12 of FIleMaker Server. If the database is currently being accessed by an IWP user and you try and hit it with a CWP request you will be locked out. The same happens in reverse.
I am not experienced enough (yet) to know where the line between CWP and IWP is. We do have a wide variety of processes accessing the system: some XML, some IWP, mostly clients of course.
We have SeedCode's Zulu Calendaring running and I am wondering if that is a contributor. There is one aspect of that that runs every 30 minutes, plus various users that can connect whenever their client is set to update (e.g. iCal subscription). I know that their system needs IWP running, but the log files seem to indicate that it is all XML connections.
I finally noted the direct correlation between the "Error 802" lines in the pe_application_log.txt file and user log in attempts in the wpc_access.txt file. Now I can at least narrow down exact timestamps and compare to yet OTHER logs to see what is happening in other places at those times.
FMI issued a bunch of bad activation codes when FMSA 12 was first released that caused this issue. You should contact support to get your activation reissued accordingly.
Sorry to be late to respond; busy few weeks.
I talked with FM Tech Support about this while at DevCon and they were saying that the problem with activation codes was restricted to a bug where CWP and IWP would COMPLETELY hose each other. I.e. nothing would work. This case, where it only intermittently doesn't work, didn't fit that model, obviously. So at least they were aware of the activation code problem...