Failed to Add a Router - Unable to Connect


When you try to add a router in Switch Port Mapper, Rogue Detection, and MAC IP List tools or from Admin --> Routers by specifying the CLI Settings, you get an error as "Unable to Connect "


The following checks are performed when a router is added in OpUtils using the CLI Settings:

  1. Whether the supplied password and prompt are correct.
  2. After verifying this, OpUtils tries to establish a telnet connection with the router. This error message is shown, when the router do not accept the connection. One possible reason could be that the maximum concurrent connection limit of that router has reached.


You can resolve this in the following ways:

  1. By closing the existing connections to that router. You can use the TCP Reset Tool in OpUtils to get the details of the current connections and to terminate the connections.
  2. By increasing the concurrent connection limit.

Applies to: Rogue Detection, Switch Port Mapper, MAC IP List

Keywords: telnet router, cli, max. connection limit, increase limit.

24/5 Support

Support will be available 24hrs a day and five days a week (Monday through Friday), excluding USA & India public holidays.

Tel : +1-888-720-9500
Email :

Speak to us

  • Join the OpUtils Community, to get instant answers for your queries, register with our Forum.
  • Tweet the latest happenings in OpUtils, follow us at Twitter.