accesslist help

Posted on 2009-02-11
Last Modified: 2012-05-06

permit tcp any eq 110 any

i have applied the above to the outbound of an interface, what does the permit statment does?

with that rule my internal server is able to connect to extermal email server

im wonderin which "any" means the external mail server

Question by:ammadeyy2020
    LVL 43

    Accepted Solution

    Is it outbound towards the email server (outbound on the VLAN interface of the mail server) or is it outbound towards the external server?

    If outbound towards the internal email server, it allows the return traffic from the external mail server.  The first any is the source, in this case the external mail server.  The second any is the destination, in this case your mail server.

    If outbound towards the external mail server, it has no effect (well, it allows source ports of 110 to any destination) this would be required for connections to your mail server on 110 (inbound connections).

    Author Comment

    its outbound towards internal mail server

    so tthat means if x.x.x.x is externail mail server
    permit tcp x.x.x.x eq 110 host

    that means recieves mail from x.x.x.x
    LVL 43

    Expert Comment

    The internal mail server makes a connection to x.x.x.x on port 110 so the access-list rule allows the return traffic where x.x.x.x has a source port of 110 and the destination is  This is needed because it is outbound toward the internal mail server.

    Featured Post

    Free Trending Threat Insights Every Day

    Enhance your security with threat intelligence from the web. Get trending threat insights on hackers, exploits, and suspicious IP addresses delivered to your inbox with our free Cyber Daily.

    Join & Write a Comment

    So, you're experiencing issues on your network and you've decided that you need to perform some tests to determine whether your cabling is good.  You're likely thinking that you may need to spend money which you probably don't have on hiring/purchas…
    The Cisco RV042 router is a popular small network interfacing device that is often used as an internet gateway. Network administrators need to get at the management interface to make settings, change passwords, etc. This access is generally done usi…
    Here's a very brief overview of the methods PRTG Network Monitor ( offers for monitoring bandwidth, to help you decide which methods you´d like to investigate in more detail.  The methods are covered in more detail in o…
    In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor ( If you're interested in additional methods for monitoring bandwidt…

    729 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    23 Experts available now in Live!

    Get 1:1 Help Now