Solved

POP Mail not Working with Cisco PIX 506 Firewall

Posted on 2004-10-22
363 Views
Last Modified: 2012-05-05
My outbound mail is working, but POP mail is not.  I can telnet to port 25, but it fails on port 110.  Do I need to open port 110 on my Cisco Firewall?  I have a NAT created and an Access Rule for POP3, but am still not able to conect to POP Server.  Any ideas?

Thanks
0
Question by:rmefford
    14 Comments
     
    LVL 79

    Expert Comment

    by:lrmoore
    the static nat and the access rule are generally all you need for any port.
    Can you post your config ? ( be sure to mask out an passwords and your public IP)
    0
     

    Author Comment

    by:rmefford
    Here is my config...thanks for the help...

    Result of firewall command: "show run"
     
    : Saved
    :
    PIX Version 6.3(3)
    interface ethernet0 auto
    interface ethernet1 auto
    nameif ethernet0 outside security0
    nameif ethernet1 inside security100
    enable password fYGjIZ.r.8FYvTjF encrypted
    passwd 2KFQnbNIdI.2KYOU encrypted
    hostname <deleted>
    domain-name <deleted>
    fixup protocol dns maximum-length 512
    fixup protocol ftp 21
    fixup protocol h323 h225 1720
    fixup protocol h323 ras 1718-1719
    no fixup protocol http 80
    fixup protocol rsh 514
    fixup protocol rtsp 554
    fixup protocol sip 5060
    fixup protocol sip udp 5060
    fixup protocol skinny 2000
    no fixup protocol smtp 25
    fixup protocol sqlnet 1521
    fixup protocol tftp 69
    names
    access-list inside_outbound_nat0_acl permit ip any 10.1.5.192 255.255.255.192
    access-list outside_access_in permit tcp any interface outside eq https
    access-list outside_access_in permit tcp any interface outside eq www
    access-list outside_access_in permit tcp any interface outside eq smtp
    access-list outside_access_in permit tcp any interface outside eq pop3
    access-list outside_access_in permit tcp any eq 81 interface outside eq 81
    access-list outside_access_in permit tcp any host <external IP> eq pop3
    access-list outside_cryptomap_dyn_20 permit ip any 10.10.5.192 255.255.255.192
    pager lines 24
    mtu outside 1500
    mtu inside 1500
    ip address outside <external IP> 255.255.255.240
    ip address inside 10.1.5.1 255.255.255.0
    ip audit info action alarm
    ip audit attack action alarm
    pdm location 10.1.5.20 255.255.255.255 inside
    pdm logging informational 100
    pdm history enable
    arp timeout 14400
    global (outside) 10 interface
    global (inside) 2004 10.1.5.51
    nat (inside) 10 0.0.0.0 0.0.0.0 0 0
    static (inside,outside) tcp interface www 10.1.5.20 www netmask 255.255.255.255 0 0
    static (inside,outside) tcp interface https 10.1.5.20 https netmask 255.255.255.255 0 0
    static (inside,outside) tcp interface smtp 10.1.5.20 smtp netmask 255.255.255.255 0 0
    static (inside,outside) tcp interface pop3 10.1.5.20 pop3 netmask 255.255.255.255 0 0
    static (inside,outside) tcp interface 81 10.1.5.20 81 netmask 255.255.255.255 0 0
    access-group outside_access_in in interface outside
    route outside 0.0.0.0 0.0.0.0 <external gateway ip> 1
    timeout xlate 0:05:00
    timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 rpc 0:10:00 h225 1:00:00
    timeout h323 0:05:00 mgcp 0:05:00 sip 0:30:00 sip_media 0:02:00
    timeout uauth 0:05:00 absolute
    aaa-server TACACS+ protocol tacacs+
    aaa-server RADIUS protocol radius
    aaa-server LOCAL protocol local
    http server enable
    http 10.1.5.0 255.255.255.0 inside
    no snmp-server location
    no snmp-server contact
    snmp-server community public
    no snmp-server enable traps
    floodguard enable
    telnet timeout 5
    ssh timeout 5
    console timeout 0
    dhcpd address 10.1.5.51-10.1.5.200 inside
    dhcpd dns <primary DNS> <secondary DNS>
    dhcpd lease 3600
    dhcpd ping_timeout 750
    dhcpd domain <domainname>
    dhcpd auto_config outside
    dhcpd enable inside
    username sctadmin password WeuL3s8PP7LAFX5X encrypted privilege 15
    username randym password t5Q1R3kVzz2m535A encrypted privilege 15
    terminal width 80
    Cryptochecksum:e7830a96a44a638f266bac00cad9de77
    : end



    0
     
    LVL 79

    Accepted Solution

    by:
    >access-list outside_access_in permit tcp any interface outside eq pop3
    >static (inside,outside) tcp interface pop3 10.1.5.20 pop3 netmask 255.255.255.255 0 0

    Those two entries should be all you need.
    Suggestions:
     1) try re-applying the acl to the interface:
          access-group outside_access_in in interface outside

     2) save your config, hard reboot the pix. Power off completely, wait 1 minute, power back up.

    Use output of "show access-list" and look for hitcounts for pop3
    0
     

    Author Comment

    by:rmefford
    Okay did that, and still POP fails.

    Show access-list shows no hits on POP3.

    I am curious...about the results of show access-list

    Result of firewall command: "show access-list"

    What is access-list outside_access_in line 6 permit tcp any host <external ip> eq pop3 (hitcnt=0)?  I notice the other access list don't have this associated with them.

    Randy


    access-list cached ACL log flows: total 0, denied 0 (deny-flow-max 1024)
                alert-interval 300
    access-list inside_outbound_nat0_acl; 1 elements
    access-list inside_outbound_nat0_acl line 1 permit ip any 10.1.5.192 255.255.255.192 (hitcnt=0)
    access-list outside_access_in; 6 elements
    access-list outside_access_in line 1 permit tcp any interface outside eq https (hitcnt=0)
    access-list outside_access_in line 2 permit tcp any interface outside eq www (hitcnt=10)
    access-list outside_access_in line 3 permit tcp any interface outside eq smtp (hitcnt=1)
    access-list outside_access_in line 4 permit tcp any interface outside eq pop3 (hitcnt=0)
    access-list outside_access_in line 5 permit tcp any eq 81 interface outside eq 81 (hitcnt=0)
    access-list outside_access_in line 6 permit tcp any host <external ip> eq pop3 (hitcnt=0)
    access-list outside_cryptomap_dyn_20; 1 elements
    access-list outside_cryptomap_dyn_20 line 1 permit ip any 10.10.5.192 255.255.255.192 (hitcnt=0)

    0
     
    LVL 79

    Expert Comment

    by:lrmoore
    >access-list outside_access_in line 6 permit tcp any host <external ip> eq pop3 (hitcnt=0)
    This line accepts pop3 from any, to the IP address, instead of using the keyword "interface"
    It is redundant to this line, and is not necessary
    >access-list outside_access_in line 4 permit tcp any interface outside eq pop3 (hitcnt=0)

    You are actually trying this from an external client, right?

    My  next suggestion would be to make sure the server's default gateway is set correctly, but since the web service works on that same server, it appears that would have to be correct....
    Can you confirm that pop3 is actually working on that server? Can you connect to it with it's private IP address OK?

    0
     

    Author Comment

    by:rmefford
    Yes, good question though.  It should also work internally b/c I have pop and smtp defined with "A" records in my DNS server.

    But from the outside everything works....except it can not log on to the POP server successfully.  And before you ask...I did verify my username and password ;)
    0
     
    LVL 79

    Expert Comment

    by:lrmoore
    Has this hitcount increased?
    access-list outside_access_in line 4 permit tcp any interface outside eq pop3 (hitcnt=0)
    You should get a hit every attempt, whether your login is accepted or not..
    You are using the Public IP address of the outside interface?

    You need to verify that you can open a POP3 client and connect to the server inside. Perhaps the pop3 service is not running?
    0
     

    Author Comment

    by:rmefford
    It has increased...so it is getting hit, why would the logon atempt fail?  Or is it something else?  yes the POP3 service is running.

    I am not sure what you mean by "you are using the public IP address of outside interface"?  I am accessing through pop.domain.com and smtp.domain.com

    Randy

    Result of firewall command: "show access-list"
     
    access-list cached ACL log flows: total 0, denied 0 (deny-flow-max 1024)
                alert-interval 300
    access-list inside_outbound_nat0_acl; 1 elements
    access-list inside_outbound_nat0_acl line 1 permit ip any 10.1.5.192 255.255.255.192 (hitcnt=0)
    access-list outside_access_in; 6 elements
    access-list outside_access_in line 1 permit tcp any interface outside eq https (hitcnt=0)
    access-list outside_access_in line 2 permit tcp any interface outside eq www (hitcnt=109)
    access-list outside_access_in line 3 permit tcp any interface outside eq smtp (hitcnt=31)
    access-list outside_access_in line 4 permit tcp any interface outside eq pop3 (hitcnt=45)
    access-list outside_access_in line 5 permit tcp any eq 81 interface outside eq 81 (hitcnt=0)
    access-list outside_access_in line 6 permit tcp any host <external ip> eq pop3 (hitcnt=0)
    access-list outside_cryptomap_dyn_20; 1 elements
    access-list outside_cryptomap_dyn_20 line 1 permit ip any 10.10.5.192 255.255.255.192 (hitcnt=0)

    0
     
    LVL 79

    Expert Comment

    by:lrmoore
    It is obvously hitting the correct IP address of the outside IP of the PIX because the hitcount is increasing.
    There is nothing in the config that could prevent the login once you connect.
    I would look at the pop3 server itself and make sure it is configured correctly.

    > yes the POP3 service is running
    But, can you actually use the POP3 client on the inside network and log in to the server?

    0
     

    Author Comment

    by:rmefford
    No, not using pop I can not connect inside.

    Curious...what could that mean?  or be?
    0
     

    Author Comment

    by:rmefford
    Okay...correction it is working from inside, when I use local IP for pop & smtp
    0
     

    Author Comment

    by:rmefford
    Okay...it is also working by external IP but not pop.domain.com, :)  Now what!
    0
     

    Author Comment

    by:rmefford
    Okay...I think I got it all working.  Thanks for your HELP!
    0
     
    LVL 79

    Expert Comment

    by:lrmoore
    Good work!

    0

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Course: JavaScript Coding - Massive 12-Part Bundle

    Regardless of your programming skill level, you'll go from basics to advanced concepts in a vast array of JavaScript subjects including Sammy.js, Agility.js, Ember.js, Node.js, jQuery, AJAX, Extjs, AngularJS, Knockout.js, and JSON.

    Hi All,  Recently I have installed and configured a Sonicwall NS220 in the network as a firewall and Internet access gateway. All was working fine until users started reporting that they cannot use the Cisco VPN client to connect to the customer'…
    If your business is like most, chances are you still need to maintain a fax infrastructure for your staff. It’s hard to believe that a communication technology that was thriving in the mid-80s could still be an essential part of your team’s modern I…
    After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
    After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…

    913 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

    17 Experts available now in Live!

    Get 1:1 Help Now