CGI upstream problem

[Philip Rhoades]

People,

I have a number of Ruby test?.cgi scripts that work fine but this one 
shows an error:fb_chatbot4.cg

2017/06/07 21:32:22 [debug] 15522#0: *32 http upstream check client, 
write event:1, "/cgi-bin/fb_chatbot4.cgi"
2017/06/07 21:32:22 [debug] 15522#0: *32 http upstream recv(): -1 (11: 
Resource temporarily unavailable)

Of course it is more complicated than the little test scripts but it has 
been working fine for a while and then stopped a few days ago without me 
noticing - I can't think what I might have done that has changed the 
situation . .  The chatbot is running and listening on the right port 
and can be talked to via local and remote shell scripts OK . .  If I run 
the fb_chatbot4.cgi script with test data it also works OK (instead of 
trying to connect from Facebook Messenger -> nginx).

Anyone got suggestions about how to debug further?

System:

   Fedora 25 x86_64
   nginx-1.10.2-1.fc25.x86_64
   fcgi-2.4.0-29.fc24.x86_64
   fcgiwrap-1.1.0-4.20150530git99c942c.fc25.x86_64

Thanks,

Phil.
-- 
Philip Rhoades

PO Box 896
Cowra  NSW  2794
Australia
E-mail:  phil at pricom.com.au