rickert@mp.cs.niu.edu (Neil Rickert) (02/22/91)
In article <1991Feb21.181945.3595@rusmv1.rus.uni-stuttgart.de> wolf@grasp2.univ-lyon1.fr (Christophe Wolfhugel) writes: >My current sendmail.cf uses MX records (OK ALL in fact). Through tries, >I've seen that MX resolution is done on the really last statement, the >$#tcp at the end of rule 0 (in some cases it's done before, but that >does not interest me).. > >Due to the really heavy traffic I general, I wish not to use the MX >records for certain category of hosts: our local systems. > >Is there any mean for temporarily disabling MX usage? (if in my domain >then do not resolve). Bad idea. The MX records are there to say where mail should go. Not using them is likely to cause misdirected mail. The only time you should not be using them is when you have specifically arranged some other way of getting the mail to that host, such as by UUCP. In that case you would need special treatment in 'sendmail.cf'. If you are worried about the time for reading nameserver records, just make sure you have your own nameserver running, and make in an unofficial secondary server for your own domain. It will download the data for your domain from a primary server, and have it readily available for fast lookups when needed. -- =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*= Neil W. Rickert, Computer Science <rickert@cs.niu.edu> Northern Illinois Univ. DeKalb, IL 60115 +1-815-753-6940
wolf@grasp2.univ-lyon1.fr (Christophe Wolfhugel) (02/22/91)
My current sendmail.cf uses MX records (OK ALL in fact). Through tries, I've seen that MX resolution is done on the really last statement, the $#tcp at the end of rule 0 (in some cases it's done before, but that does not interest me).. Due to the really heavy traffic I general, I wish not to use the MX records for certain category of hosts: our local systems. Is there any mean for temporarily disabling MX usage? (if in my domain then do not resolve). Please respond directly by mail, I'll summarize for the net. Thanx -- Christophe Wolfhugel (on irc: Zolf) | Email: wolf@grasp1.univ-lyon1.fr INSA Lyon - Departement Informatique | IRC'admin at node grasp1.univ-lyon1.fr 69621 Villeurbanne Cedex, France | Fax: (+33) 72 44 08 00
wolf@grasp2.univ-lyon1.fr (Christophe Wolfhugel) (02/27/91)
Well, I got the solution to this problem. Here it is, hoping it might help other users. The idea is not to disable temprarily the MX record, but to use 2 (or more) MX records per host. Each of the local hosts at our domain currently has one 'MX 10' record pointing to our MX. So when my listserv sends mail locally it goes through the MX, what I don't want. By adding a second MX record for each local host pointing to the host itself (at MX 0 record) the new scheme is: - first try to deliver to MX 0 (the host itself) - if it fails deliver to the next MX (in this case MX 10). Another solution that I've been suggested is to setup a second DNS that can be only accessed locally and with each host being it's own MX. Thanks to Neil Rickert and Mark D. Baushke for their precious help. -- Christophe Wolfhugel (on irc: Zolf) | Email: wolf@grasp1.univ-lyon1.fr INSA Lyon - Departement Informatique | IRC'admin at node grasp1.univ-lyon1.fr 69621 Villeurbanne Cedex, France | Fax: (+33) 72 44 08 00