503 status code

[andan andan]

Hi all.

We have Varnish trunk rev2980 running in production.

All works fine except some errors logged by varnishncsa with the 503
status code. All these errors are associated to pass rules.

We have tried to increase .connectimeout without sucess.

Apparently, the backend (a load balancer in front of several
webservers), works fine, testing it, with stress tools, curl and
others.

Any ideas ?

Thank You very much.
Best regards.