Guest

Preview Tool

Cisco Bug: CSCtd16493 - port xx in use by system error while configuring NAT

Last Modified

Jan 24, 2017

Products (1)

  • Cisco IOS

Known Affected Releases

12.2(18)SXF17 12.2(33)SXH8

Description (partial)

Symptom:

Static PAT configuration command may fail with the message: "%Port 25 is being used by system".

Conditions:

This may happen when another similar command is present for the same port, but for the different outside IP address or interface. For example:

ip nat inside source static tcp 192.168.2.2 25 192.168.1.1 25 extendable
ip nat inside source static tcp 192.168.2.2 25 10.48.67.214 25 extendable 
%Port 25 is being used by system min25

This happens only if the outside (global) IP address belongs to the router or router interface is specified instead of IP:

ip nat inside source static tcp 192.168.2.2 25 int vl 98 25
ip nat inside source static tcp 192.168.2.2 25 int vl 1 25
%Port 25 is being used by system
Bug details contain sensitive information and therefore require a Cisco.com account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.