two instances of dccm

Vernon Schryver
Thu Jul 1 14:12:10 UTC 2004

> 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" ?

> 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.

Vernon Schryver

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