Date:  10/26/2007 09:51:51 AM Msg ID:  003545
From:  David Hempy Thread:  003545
Subject:  \"No Channels Active\" every other hit
We've been running FoxWeb for about ten years now.  We're still running v2.6, with 1.x compatibility turned on.  We've bought a license to upgrade to v4, but haven't installed it yet.
 
I've made some updates to our code recently on our development server.  I've now got a problem where exactly every other hit instantly returns "No Channels Active".  Between these "even" error pages, all the "odd" hits return just fine. 
 
I've restarted and rebooted, with no change.  When I run as an application instead of a service, the behavior goes away.  When I change back to a service, it runs fine for a while (minutes or ?maybe? an hour) before going into the even-odd mode again. 
 
I find no entries in the error log or in fwstart.log.
 
I added a sendmail as the first line of fw_enter.prg and the last line of fw_exit.prg.  For succesful hits, I get both the Starting and Ending emails.  For the No Channels hits, I get no emails.  I've never gotten a Starting email without its partner Ending email.

I have changed the number of channels, with no effect. 

I notice only channel 1 is being used.  Even with several simultaneous hits from separate browsers, they queue up for Channel 1, while 2-4 sit Waiting.

Possibly related, the code I was updating was testing a race condition for two channels inserting values into a table at the same time.  In those tests (before I started getting the No Channels errors), I could never get the race condition to occur.  Even when I put a "wait timeout 5" delay in the critical code, I could not recreate the race condition on the development server.  Instead of having two simultaneous hits go to channel 1 and 2 to duke it out, they both were serviced by channel 1.  So the second hit didn't return to the browser until 10 seconds had passed.  Again, I'm not sure if this is related, as this was occurring consistently before I ever saw my first No Channels error.


So now I'm not sure where to go.  These are the options I can think of, in the order I'm likely to try:

  1. Roll back my code edits from the last week.
  2. Reinstall our present version of FoxWeb (v2.6). 
  3. Upgrade FoxWeb to v4.
  4. Upgrade Visual FoxPro from v8 to v9. 
FWIW, we are planning both upgrades at this time, but I'm hesitant to make changes to a system that is already not stable.  I've got a hunch the problem is from my code updates, just based on timing, but most of the clues indicate it is something with the FoxWeb Broker.
 
None of these recent updates have been published to our production server, and we are not seeing any of our issues there.
 
Any suggestions?  Has anyone seen this even-odd behavior before?

Thanks in advance,
-dave

ps.  I'll follow up, whatever the solution ends up being.



--
David Hempy
Internet Database Administrator
Kentucky Educational Television
(859)258-7164 - (800)333-9764
 
--
David Hempy
Internet Database Administrator
Kentucky Educational Television
(859)258-7164 - (800)333-9764