Proxy problem: "imap-login: Error: proxy(USERNAME): connect(10.x.x.178, 993) failed: Cannot assign requested address (after 0 secs, local=10.x.x.104)"

[Timo Sirainen]

On 16 Oct 2014, at 06:26, Ralf Hildebrandt <r at sys4.de> wrote:

> After fixing the "duplicate compression" problem, we're now
> encountering 
> 
> "imap-login: Error: proxy(USERNAME): connect(10.x.x.178, 993) failed: Cannot assign requested address (after 0 secs, local=10.x.x.100)"
> 
> in the logs. We already tried raising the ulimit, the max number of
> open files. Once we reach about 25k connections, we're getting the
> error above... for all local addresses. It seems as if the system
> cannot create any more outgoing connections.

I'd guess you're running out of TCP ports.

> We're using multiple local addresses when proxying to the backends

How are you doing the multiple local addresses? In v2.2.14 there's login_source_ips setting intended to solve this problem. http://wiki2.dovecot.org/PasswordDatabase/ExtraFields/Proxy