Cyrus trying to resolve lan ip

Thu Oct 24 11:36:20 EDT 2002

Running a name server seems a bit drastic to get rid of this 
problem..... And a hosts file entry for all workstations is also not an 
option.....
Is there a way to have Cyrus not do those lookups?? or is it not done by 
Cyrus??

If there is no other way I will install named...... :-(

Russell Packer wrote:

>You are correct, the problem is with DNS.
>
>My personal favourite for this one is to run DNS on the machine with empty records for your networks (or real ones, if you like!).
>
>The other option is to use the hosts file.
>
>Finally, you can configure each application (eg. sendmail) not to perform the DNS check.
>
>-----Original Message-----
>From: J.A.J. van Belkum [mailto:aukjan at gfo.nl]
>Sent: 24 October 2002 14:46
>To: info-cyrus at lists.andrew.cmu.edu
>Subject: Cyrus trying to resolve lan ip
>
>
>Hi y'all,
>
>I am running cyrus on a RH7.1 box icw Postfix and MySQL.  All of a 
>sudden two of my servers, at different sites started showing  slow 
>reaction times (exacly 20 seconds).  They are both connected through the 
>same provider.... So I grabbed my tcpdump and started searching.... now 
>I got the following dump:
>
>15:14:04.754162 eth1 < 192.168.0.50.1445 > 192.168.0.254.imap: S 18257605:18257605(0) win 8192 <mss 1460,nop,nop,sackOK> (DF)
>15:14:04.754288 eth1 > 192.168.0.254.imap > 192.168.0.50.1445: S 3874304414:3874304414(0) ack 18257606 win 5840 <mss 1460,nop,nop,sackOK> (DF)
>15:14:04.754692 eth1 < 192.168.0.50.1445 > 192.168.0.254.imap: . 1:1(0) ack 1 win 8760 (DF)
>15:14:04.769740 eth0 > 62.177.161.90.2908 > 213.197.28.3.domain: 50561+ PTR? 50.0.168.192.in-addr.arpa. (43) (DF) [tos 0x8] 
>15:14:09.775391 eth0 > 62.177.161.90.2910 > 213.197.30.28.domain: 50561+ PTR? 50.0.168.192.in-addr.arpa. (43) (DF) [tos 0x8] 
>15:14:12.295410 eth0 > 62.177.161.90.2911 > 213.197.30.28.domain: 7750+ PTR? 50.0.168.192.in-addr.arpa. (43) (DF) [tos 0x8] 
>15:14:14.785303 eth0 > 62.177.161.90.2908 > 213.197.28.3.domain: 50561+ PTR? 50.0.168.192.in-addr.arpa. (43) (DF) [tos 0x8] 
>15:14:17.305325 eth0 > 62.177.161.90.2909 > 213.197.28.3.domain: 7750+ PTR? 50.0.168.192.in-addr.arpa. (43) (DF) [tos 0x8] 
>15:14:19.795301 eth0 > 62.177.161.90.2910 > 213.197.30.28.domain: 50561+ PTR? 50.0.168.192.in-addr.arpa. (43) (DF) [tos 0x8] 
>15:14:22.315379 eth0 > 62.177.161.90.2911 > 213.197.30.28.domain: 7750+ PTR? 50.0.168.192.in-addr.arpa. (43) (DF) [tos 0x8]
>15:14:24.806469 eth1 > 192.168.0.254.imap > 192.168.0.50.1445: P 1:55(54) ack 1 win 5840 (DF)
>15:14:24.807308 eth1 < 192.168.0.50.1445 > 192.168.0.254.imap: P 1:18(17) ack 55 win 8706 (DF)
>15:14:24.807411 eth1 > 192.168.0.254.imap > 192.168.0.50.1445: . 55:55(0) ack 18 win 5840 (DF)
>15:14:24.807611 eth1 > 192.168.0.254.imap > 192.168.0.50.1445: P 55:243(188) ack 18 win 5840 (DF)
>15:14:24.809131 eth1 < 192.168.0.50.1445 > 192.168.0.254.imap: P 18:46(28) ack 243 win 8518 (DF)
>15:14:24.813409 eth1 > 192.168.0.254.imap > 192.168.0.50.1445: P 243:267(24) ack 46 win 5840 (DF)
>15:14:24.815208 eth1 < 192.168.0.50.1445 > 192.168.0.254.imap: P 46:57(11) ack 267 win 8494 (DF)
>15:14:24.815498 eth1 > 192.168.0.254.imap > 192.168.0.50.1445: P 267:279(12) ack 57 win 5840 (DF)
>15:14:24.816289 eth1 < 192.168.0.50.1445 > 192.168.0.254.imap: P 57:63(6) ack 279 win 8482 (DF)
>15:14:24.816460 eth1 > 192.168.0.254.imap > 192.168.0.50.1445: P 279:298(19) ack 63 win 5840 (DF)
>15:14:24.817207 eth1 < 192.168.0.50.1445 > 192.168.0.254.imap: P 63:84(21) ack 298 win 8463 (DF)
>
>
>
>It looks like cyrus is trying to resolve the internal IP address... 
>which it shouldn't do.  This probabely points to a change in the Network 
>of the provider, now that they both take 20 seconds to get answers... 
> Before yesterday they were running just fine, but now I do not want the 
>servers to check the DNS records.... How can I do this, or might this be 
>some other problem???
>
>
>bash$ route   
>Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
>62.177.161.88   0.0.0.0         255.255.255.252 U     0      0        0 eth0
>192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
>127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
>0.0.0.0         62.177.161.89   0.0.0.0         UG    0      0        0 eth0
>
>
>Any suggestions are Welcome!!
>
>Thanks,
>
>    Aukjan van Belkum
>
>
>
>
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>  
>