Why is Novell Groupwise broken?

Stephen Carter stephen@retnet.co.uk
Mon Dec 5 09:38:18 UTC 2005


>>> Vernon Schryver <vjs@calcite.rhyolite.com> 12/04/05 9:50 PM >>>
>> From: Gary Mills 
>
>> One site that failed to retry delivery claims to be running GroupWise
>> 6.5 SP5.  Either Novell broke it in SP5, or the site has it badly
>> configured.  I'm guessing that it is a configuration error.  The admin
>> said ``The issue is with the embedded initial retry in GWise GWIA
>> (SMTP) of 20 minutes which is too long for most greylist solutions.''
>> I don't know how he configured it.  Twenty minutes seems reasonable
>> to me.  The SMTP standard recommends 30 minutes.
>
>Something is askew in what that administrator seems to be be saying,
>and not only that section 4.5.4.1 of RFC 2821 says
>
>]  The sender MUST delay retrying a particular destination after one
>]  attempt has failed.  In general, the retry interval SHOULD be at
>]  least 30 minutes; however, more sophisticated and variable strategies
>
>Isn't the problem with these particular SMTP clients that they fail to
>retransmit at all instead of waiting 20 minutes to retransmit?  Contrary
>to the administrator's words about "most greylist solutions," I think
>the most common greylist embargoes are far longer than 20 minutes.
>
>How would a 20 minute or any retry be "too long" for any greylist
>filter?  The retry delay should be longer than the filter's embargo,
>but not "too long."  However, the only plausible notion of "too long"
>I can see involves not computer but only human user impatience.
>
>The default dccm/dccifd greylist embargo is 4.5 minutes, because my
>measurements of spammers that did retransmit (esp. some spamware
>popular among 419 spammers) found very few that persist for 5 minutes.
>On the other hand, sendmail in major commercial UNIX releases has been
>configured to retransmit after 15 minutes, I've seen many SMTP clients
>configured to retransmit after 5 minutes, and then there are the sendmail
>and other installations that use some crazy ("backup server"?) schemes
>to retransmit after less than 1 second.
>
>Vernon Schryver    vjs@rhyolite.com

Although the GW admin sounds like they are properly aware of this issue,
I agree with Vernon that something doesn't sound right.

GroupWise isn't as configurable as most Unix style systems for simplicity,
and the only setting I know of (which is to say there may be others) that
relate to deferred message retries is the option 'Maximum number of
hours to retry a deferred message' which by default is set to 96 hours.

It is possible to customise the status messages for undeliverable e-mail,
which is documented in the GroupWise online documentation.

Although they have upgraded to GW 6.5 SP5, it is also possible that the
GWIA (GroupWise Internet Agent) component hasn't been updated.

Gary, I'm happy to setup a test box running GW 6.5 w/ SP5 but at the
moment that box is a test bed for the latest Maia Mailguard SVN which
I will be finished with in a couple of days. After I'm done I'll set it up
with GW 6.5 SP5 on NetWare and let you know then test again as I
already have done with my 6.5 SP4 setup.

SteveC




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