two instances of dccm

Juergen Georgi
Mon Jul 5 07:47:14 UTC 2004

On Thu 2004-07-01 (08:12), Vernon Schryver wrote:
> > From: "Juergen Georgi" <>
> > I need to run two instances of dccm on the same host.
> > Using sendmail's new InputMailFiltersList key in
> > DaemonPortOptions, the first sendmail daemon listens to
> > ip1 and talks to a greylisting dccm, the second daemon
> > on ip2 talks to another dccm without greylisting. 
> Could you acheive the same or better effects by using per-user
> whiteclnt files, some containing "option greylist-off" and others
> containing "option greylist-on" ?
Our machines do not have user accounts, they act as relays only.
We also do not have complete knowlegde of all valid destination
email adresses, so we cannot configure userdirs. We would
need something like "domaindirs", which allow for per-domain 
whiteclnt files. But dccm doesn't offer such feature (yet?).
Anyhow, I still have my doubts about the userdir concept.
What happens if a message has more than one destination
address with conflicting greylist settings? sendmail
can only reject or accept the whole message.

> > With different "-l" and "-R" options I can easily start 
> > two instances of dccm. My concern is the map file and
> > the whiteclnt.dccw hash table. Can they be shared
> > by two dccm processes?  
> Those files can be shared, but if your system is busy, should not be.
> The mail file must be changed with new versions of the round trip
> times (RTTs) to the DCC servers.  The whiteclnt.dccw file must be rebuilt
> if the whiteclnt file changes.  Locking resolves conflicts among
> DCC clients, usually dccproc with other instances of dccproc or
> dccproc with dccm or dccifd. 
> However, I'd try to avoid overheating those locks by giving the
> two dccm processes separate DCC home directories.  I would build
> them with two different values for `./configure --homedir=XXX`.
> This would also simplify starting the two dccm daemons, since
> symbolic links to the two rcDCC files could be put wherever your
> flavor of UNIX wants them, each using the distinct dcc_conf file needed
> to turn greylisting on or off.

Hmm, I'd rather avoid to install two different binaries. I'll probably
make a another init script which just starts dccm with "-h XXX". 


-Juergen Georgi

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