Write error, len = 69696/260844, errno = Success

[Tollef Fog Heen]

]] Václav Bílek 

| Is there anyone who can point us where to look to find the problem?

As you are getting a write error and not a timeout, I would take a look
at any load balancers or similar that are configured to kill connections
that take more than 5s.  It doesn't look like anything Varnish is doing.

-- 
Tollef Fog Heen 
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