nat port 389 on a cisco 1841 router

Posted on 2011-10-10
Last Modified: 2012-06-21
I have a cisco 1841 router on my network that also acts as our firewall. I'm trying to allow port 389 (ldap) and forward it to an internal server so my external website can query active directory.

I set up following rule as #1 in my access-list (with xx.xx.xx.xx as my public IP address)

9 permit tcp any host  eq 389

And I set up the following for NAT
Pro Inside global      Inside local       Outside local      Outside global
tcp xx.xx.xx.xx:389      ---                ---

However when I cannot bind to my ldap server from the internet and when I run nmap on the router I get this

80/tcp    open   http
443/tcp   closed https
49157/tcp closed unknown

No port 389? Can someone help?

Question by:steiner470
    LVL 5

    Expert Comment

    by:Prashant Shrivastava
    You need to define static rule here:

    ip nat inside source static tcp <insert-internal-ip-address-here> 389 interface <external-interface> 389


    Author Comment

    @Prash - yes I did that already (thats why you can see that NAT entry in my table above).
    LVL 15

    Accepted Solution

    firewall rules
    ip inspect
    could be on both extenal interface or internal.
    the nat command should not require a reboot.


    Author Closing Comment

    It was the firewall preventing it, thanks

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