Forward request through IPTables

Posted by Jeremy on Server Fault See other posts from Server Fault or by Jeremy
Published on 2012-10-31T20:18:07Z Indexed on 2012/10/31 23:03 UTC
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iptables

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nat

I have a server running CentOS with 50 IP addresses on it. I was looking to use it as a proxy server (not just HTTP), but can't find any examples on how to set up the IP Tables.

I want to proxy into IP-X and have my request look like its coming from IP-X.

I currently do this on squid, but we need to proxy more than just HTTP traffic. Here is an example of the squid config:

acl users src 255.255.255.255 #Locked down IP address
acl all src 0.0.0.0/0.0.0.0

# http access rules
http_access deny !users
http_access allow users
http_reply_access deny !users
http_reply_access allow users
icp_access deny all

#ip_addresses
acl ip3 myip 10.1.1.3
tcp_outgoing_address 10.1.1.3 ip3

Do to IP restrictions I need access to IMAP, POP and SMTP through a proxy. I want to use the server I already pay for that has 50 IPs on it as the proxy server.

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