Re: [cobalt-users] (RaQ2) No reverse lookup.

[jk@xxxxxxxxxxxx (Jens Kristian Søgaard)]

Ariel Manzur <punto@xxxxxxxxxxxx> writes:

> I have some users that connect to internet using this ISP, and the DNS
> server of the ISP is down, so there is no reverse lookup for theis IP
> addresses. For ex., a gut uses "209.13.244.13", but when I do "nslookup
> 209.13.244.13" I get "server failed".

> Because of this, they can't use FTP, POP3 and SMTP.

> So, is there any way to disable the reverse lookup of the guests for this
> services?

Yeah, ofcourse. I suppose all the services you are having trouble with
are all using inetd (they are, if you're using the standard
setup). Then you have two options: either completely disable reverse
lookups, or adjust the timeout to be very short.

To disable reverse lookups, you'll have to recompile
programs. Probably not what you want.

To adjust the timeout, edit the file /etc/hosts.allow, and find the
lines corresponding to the service you with to setup.

Eg:

in.ftpd: ALL 

And add this option:

in.ftpd: ALL : rfc931 1

This should give a 1 second timeout; you could try setting it to zero
too, but I don't know what effect you'll get.


-- 
Jens Kristian Søgaard,
jk@xxxxxxxxxxxx -- http://www.jksoegaard.dk/
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