LinuxQuestions.org
Help answer threads with 0 replies.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
Reload this Page Iptables problem sending mails
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices


Reply
  Search this Thread
Old 02-11-2006, 02:19 PM   #1
Tekorei
LQ Newbie
 
Registered: Feb 2006
Posts: 2

Rep: Reputation: 0
Iptables problem sending mails

Hi there

I got this problem for sending mails outgoing mi LAN:

mail log output:
Code:
Feb 11 17:53:50 e2kserver postfix/smtp[5034]: 506D5A803B: to=<recipient@gmail.com>, relay=none, delay=3786, status=deferred (Host or domain name not found. Name service error for name=gmail.com type=MX: Host not found, try again)
I think my /etc/resolv.conf is ok, it looks like this:

Code:
search e2k.com.py
nameserver 200.85.32.2 (ISP DNS Server)
nameserver 200.85.32.3 (ISP DNS Server)
nameserver 127.0.0.1
Something I noticed is when I stop the iptables service the mails are sent, but when I start the iptables service again it doesnt work..

this is my iptables -L output:

Code:
Chain INPUT (policy DROP)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere
valid-src  all  --  anywhere             anywhere
ACCEPT     tcp  --  anywhere             anywhere            tcp spts:1024:65535 dpt:ssh state NEW
ACCEPT     tcp  --  anywhere             anywhere            tcp spts:1024:65535 dpt:http state NEW
ACCEPT     tcp  --  anywhere             anywhere            state RELATED,ESTABLISHED
ACCEPT     all  --  192.168.0.0/24       anywhere
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:domain
ACCEPT     udp  --  anywhere             anywhere            udp dpt:domain
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:pop3
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:ftp
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:ftp-data

Chain FORWARD (policy DROP)
target     prot opt source               destination
valid-src  all  --  anywhere             anywhere
valid-dst  all  --  anywhere             anywhere
ACCEPT     all  --  anywhere             anywhere            state NEW,RELATED,ESTABLISHED
ACCEPT     all  --  anywhere             anywhere            state RELATED,ESTABLISHED

Chain OUTPUT (policy DROP)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere
valid-dst  all  --  anywhere             anywhere
ACCEPT     all  --  anywhere             anywhere            state RELATED,ESTABLISHED
ACCEPT     tcp  --  anywhere             anywhere            state NEW,RELATED,ESTABLISHED
ACCEPT     all  --  anywhere             192.168.0.0/24
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:domain
ACCEPT     udp  --  anywhere             anywhere            udp dpt:domain
ACCEPT     tcp  --  anywhere             anywhere            tcp spt:domain
ACCEPT     udp  --  anywhere             anywhere            udp spt:domain
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:pop3
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:smtp

Chain valid-dst (2 references)
target     prot opt source               destination
DROP       all  --  anywhere             16.0.0.0/4

Chain valid-src (2 references)
target     prot opt source               destination
DROP       all  --  0.0.0.0/8            anywhere
DROP       all  --  ip-72-16-0-0.valornet.com/12  anywhere
DROP       all  --  92.168.0.0/16        anywhere
DROP       all  --  16.0.0.0/4           anywhere
DROP       all  --  40.0.0.0/5           anywhere
DROP       all  --  27.0.0.0/8           anywhere
DROP       all  --  0.0.0.0/8            anywhere
DROP       all  --  anywhere             255.255.255.255
DROP       all  --  169.254.0.0/16       anywhere
what could be wrong?
 
Old 02-11-2006, 02:29 PM   #2
gilead
Senior Member
 
Registered: Dec 2005
Location: Brisbane, Australia
Distribution: Slackware64 14.0
Posts: 4,141

Rep: Reputation: 168Reputation: 168
Can you try running it without the valid-src or valid-dst chains? Since your policy is set to DROP for the INPUT, FORWARD and OUTPUT chains, anything that you haven't ACCEPTed will be dropped anyway.
 
Old 02-16-2006, 07:56 PM   #3
Tekorei
LQ Newbie
 
Registered: Feb 2006
Posts: 2

Original Poster
Rep: Reputation: 0
I changed the firewall rules following some general indications from tldp.org

the server now does send outgoing mails, but I cant access any external host on port 25 or 110 through my LAN.. or the server himself on port 25/110

is there any PREROUTING or POSTROUTING rule that I should add to my iptables to allowing my LAN for sending outgoing mails?

this is my current iptables -L:

Code:
Chain INPUT (policy DROP)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp spt:smtp
ACCEPT     udp  --  anywhere             host33-10.wireless.com.py udp dpt:domain
ACCEPT     udp  --  host33-10.wireless.com.py  host33-10.wireless.com.py udp spt:domain
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp spt:domain
ACCEPT     tcp  --  192.168.0.0/24       anywhere            tcp dpt:ssh
ACCEPT     tcp  --  192.168.0.0/24       anywhere            tcp spt:ssh
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py tcp dpt:smtp
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py tcp spt:smtp
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py tcp dpt:pop3
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py tcp dpt:http
ACCEPT     udp  --  anywhere             host33-10.wireless.com.py udp dpt:domain
ACCEPT     udp  --  host33-10.wireless.com.py  host33-10.wireless.com.py udp spt:domain
ACCEPT     udp  --  inet2.telecel.com.py  host33-10.wireless.com.py udp spt:domain
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp spt:domain
ACCEPT     tcp  --  inet2.telecel.com.py  host33-10.wireless.com.py tcp spt:domain
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp spt:pop3
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py tcp spt:smtp
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py tcp spt:ftp
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py tcp spt:ftp-data
ACCEPT     tcp  --  anywhere             host33-10.wireless.com.py
ACCEPT     all  --  192.168.0.0/24       anywhere

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy DROP)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp dpt:smtp
ACCEPT     udp  --  host33-10.wireless.com.py  anywhere            udp spt:domain
ACCEPT     udp  --  host33-10.wireless.com.py  host33-10.wireless.com.py udp dpt:domain
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp dpt:domain
ACCEPT     tcp  --  anywhere             192.168.0.0/24      tcp dpt:ssh
ACCEPT     tcp  --  anywhere             192.168.0.0/24      tcp spt:ssh
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere            tcp spt:smtp
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere            tcp dpt:smtp
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere            tcp spt:pop3
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere            tcp spt:http
ACCEPT     udp  --  host33-10.wireless.com.py  anywhere            udp spt:domain
ACCEPT     udp  --  host33-10.wireless.com.py  host33-10.wireless.com.py udp dpt:domain
ACCEPT     udp  --  host33-10.wireless.com.py  inet2.telecel.com.py udp dpt:domain
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp dpt:domain
ACCEPT     tcp  --  host33-10.wireless.com.py  inet2.telecel.com.py tcp dpt:domain
ACCEPT     tcp  --  host33-10.wireless.com.py  host33-10.wireless.com.py tcp dpt:pop3
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere            tcp dpt:smtp
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere            tcp dpt:ftp
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere            tcp dpt:ftp-data
ACCEPT     tcp  --  host33-10.wireless.com.py  anywhere
ACCEPT     all  --  anywhere             192.168.0.0/24
host33-10.wireless.com.py = my servers host (given by the ISP)
inet2.telecel.com.py = ISP DNS host
 
  


Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem sending nonlocal mails in sendmail s1mpl1c1ty Linux - Newbie 4 08-29-2005 02:57 AM
Sending e-mails via a C++ program The_Nerd Programming 6 12-05-2004 09:56 PM
Sending mails using port 25 rabeea Linux - Security 10 08-16-2004 11:53 PM
qmail not sending mails spank Linux - Software 0 05-21-2004 12:08 PM
Sending mails with eXtremail Ivanhoe Linux - Networking 2 12-31-2002 09:34 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 04:24 AM.

Contact Us - Advertising Info - Rules - Privacy - LQ Merchandise - Donations - Contributing Member - LQ Sitemap -
Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration