nat port 389 on a cisco 1841 router

Posted on 2011-10-10
Medium Priority
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
  • 2

Expert Comment

by:Prashant Shrivastava
ID: 36945107
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

ID: 36945662
@Prash - yes I did that already (thats why you can see that NAT entry in my table above).
LVL 15

Accepted Solution

greg ward earned 2000 total points
ID: 36948362
firewall rules
ip inspect
could be on both extenal interface or internal.
the nat command should not require a reboot.


Author Closing Comment

ID: 36952537
It was the firewall preventing it, thanks

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