LinuxQuestions.org - squid proxy + pop3/smtp + iptables

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squid proxy + pop3/smtp + iptables

Hi there,

I'm a newbie, trying to configure squid proxy server, I'm able to share web but at my client site which has windows xp is not able to receive emails, the same I was doing on windows 2k3 server using ISA and getting all emails in outlook.

We have a broadband whose LAN IP is 192.168.1.5 which is connected to external interface of gw 192.168.1.1 Internal interface ip of gw is 10.11.0.1.

I've explored a lot got some iptables rules but not able to solve the issue. still struggling. please help me out.

can you post your current iptables rule set?

there are no rules in iptables, I'm not using firewall (disable)...

What does squid have to do with POP3 ?

Maybe you can pick just (1) problem, and ask that question, or pose that problem here. You are asking too much, with too little detail.

Are you sure iptables isn't running - I seem to recall seeing a thread recently where the poster had disabled the firewall through the GUI, but it was still causing problems.

i think the problem is your squid is the only way to internet and since pop and smtp does not use squid you can get mails.

in that case you have to masquerade using iptables and have to use your linux box as the default gateway for your internal pcs.

This problem can be solved by configuring squid as transparent proxy mode.
Search LQ forums and you will find it how to do it.

Hi thanks for you support, I've configured it as transparent proxy but still not able to resolve, please suggest me the iptables masquearding rules..

This will help you to set up transparent squid:

http://www.cyberciti.biz/tips/linux-...uid-howto.html

Quote:

Originally Posted by shahsaifi (Post 3206699)

i m facing the same problem
only windows 2003 server n windows 98 users can access the emails in outlook but windows xp users are not able to access outlook emails

wat can i do pls help to solve de problem

i hv already done dis

1 > /proc/sys/net/ipv4/ip_forward

iptables -t nat -A PREROUTING -p TCP --dport 80 -j REDIRECT --to-port 3128
iptables -t nat -A POSTROUTING -p TCP --dport 110 -j MASQUERADE
iptables -t nat -A POSTROUTING -p TCP --dport 25 -j MASQUERADE

also for https
iptables -t nat -A POSTROUTING -p TCP --dport 443 -j MASQUERADE
iptables -t nat -A POSTROUTING -p TCP --dport 563 -j MASQUERADE

service iptables save

service iptables restart

there is no firewall running linux machine
n
on xp i hv also checked by disabling antivirus n firewall

but still i m unable to solve my problme

pls help me to solve de prob

Hi there,
try these rules:-

clients-------switch----eth1--linux--eth0--------internet

& rules for masquerading:
iptables -F
service iptables save
iptables -A POSTROUTING -t nat -s 192.168.200.0/24 -j MASQUERADE
iptables --append FORWARD --in-interface eth1 -j ACCEPT
service iptables save
echo 1 > /proc/sys/net/ipv4/ip_forward