Re: [cobalt-users] [Qube 3] Mail Sending Problem

["dr. mikey" <mikey@xxxxxxxxxxxxxxxxx>]

Andy Brown wrote:
> 
> Probably not the case, but have you checked the DNS records for the
> remote machines?? As typical time-outs like you're describing sound
> classic of failing DNS.
> Quick test is for the example above, getting onto the rack and doing an
> nslookup on their address and see if it can resolve the IP address to a
> host-name. If not, then that could be the heart of the problem here.

hi brian, here is another possibility along the lines of what andy
mentioned.

we also have a qube3 set up similarly to yours (minus the dns server), and
we also had no problem with pop but experienced extreme delays with smtp. 
well, after searching in the archives i found an article from rodolfo (where
has he been lately?) about dns timeouts.  his explanation was that the dns
times out because none of the internal clients are actually listed in the
dns, which contains address records for systems on the internet rather than
your intranet.  the solution was to add the internal dhcp assigned ip
addresses for each client on the lan to the "/etc/host" file (because the
hosts file is checked before dns).  this way, when the system checks the
hosts file it finds a record matching the client and never even needs to
look at the dns records.  the following syntax is used for adding ip's to
the hosts file:

192.168.0.1 <tab> ip-0-1.internal.net <tab> ip-0-1

  where "192.168.0.1" is the internal dhcp assigned ip address,
  "ip-0-1.internal.net" is the full name for the client,
  and "ip-0-1" is the hostname for the client.

as rodolfo explains in his post, and which i followed to great effect, use
excel to prepare the text to add to the hosts file because the autonumber
feature makes it very easy to generate all possible ip addresses that the
dhcp server might hand out.  the domain name and host names aren't that
important, since they are only used internally.  i followed his example,
substituting my domain name for "internal.net", but leaving the host name
the same (i.e., "ip-0-1", ip-0-2", etc.)

anyway, here is my recent post describing how this fixed our problems:
http://list.cobalt.com/pipermail/cobalt-users/2001-August/051334.html

and rodolfo's original article is here:
http://list.cobalt.com/pipermail/cobalt-users/2001-April/039736.html

perhaps this helps you, perhaps not.  good luck in any case,

mikey.

-- 
mike songster                  work1:           www.biosearchtech.com
mikey@xxxxxxxxxxxxxxxxx        work2:  www.chem.umn.edu/orgs/ampepsoc

an eye for an eye leaves the whole world blind
                                                 gandhi