[stunnel-users] Connection rejected: too many clients (>=500)?

Ludolf Holzheid lholzheid at bihl-wiedemann.de
Tue Nov 18 21:27:28 CET 2008

On Tue, 2008-11-18 11:21:38 -0800, Chris Charman wrote:
> Hey folks --
> Can anyone tell me where the max number of clients is configured in 4.21?
> I'm running okay for a while, but then I end up with repeated messages as
> below in the logs:
> [..]
> ------------- Config below -----------------
> ulimit
> unlimited

Hi Chris,

At least for my bash, 'ulimit' without any options returns the limit
for the file size. To get the limit for the number of files, I have to
type 'ulimit -n' or 'ulimit -a' (and get 1024).

On our linux box, stunnel logs the following on startup:
> FD_SETSIZE=1024, file ulimit=1024 -> 500 clients allowed
which seems to match your observation.

I vaguely remember the limit for the number of open files on linux can
be adjusted somewhere in the /proc file system, but I don't really

In any case, the limit you are hitting is set by the operating system.



Ludolf Holzheid             Tel:    +49 621 339960
Bihl+Wiedemann GmbH         Fax:    +49 621 3392239
Floßwörthstraße 41          e-mail: lholzheid at bihl-wiedemann.de
D-68199 Mannheim, Germany

More information about the stunnel-users mailing list