Our pound balancer is serving quite some traffic and from time to time I 
see in the logs this line (10.1.20.21 is one of the backends, but it 
these lines appear for all backends, not just this one)

pound: response error read from 10.1.20.21:80: Success

I was wondering, what exactly does that mean? Using word "error" and 
"Success" in one line is a bit confusing to me :) Can anyone shed some 
light on what is actually happening? Does pound disable this backend in 
this occasion?

Thanks.
[...]