Connect Switch-Router using Auxiliary Port (Aux Port)

Connect Switch/Router using Auxiliary Port (Aux Port)

Routers and Switches are the Networking devices that are used to create a wide variety of Networks. To utilize the functionalities they provide, these Networking Devices (Routers and Switches) needs to be configured according to the requirements and situations of Auxiliary Port. To configure the device, you need to connect to it first. There are several methods of Connecting to the Router, with each having its advantages and limitations. To know more about how to Connect Switch/Router using Auxiliary Port (Aux Port), keep reading this article till the end.

While for day to day to configuration and management activities of  Router and Switch connecting to them over Network using telnet, SSH or web-based methods are no doubt the one we would be going for, But in the life of Network Administrators often comes the situations when the target device loses its network connectivity due to various reasons, such as network media fault or even when the administrators lock himself inside the device due to configuration mistakes. In such situations, you would need to near the device and connect to the Console port of the Router/ Switch to resolve the issue.

It works most of the time, but the situation becomes more severe when the real Administrator of the Network Device is quite far and reaching the location of Network devices in each such condition may not be efficient in terms of both the time and money.

Here is what the Aux port comes to rescue, yes it could be configured in such a way so that, one would be able to get the Console Connection to the Device over the Network, In this way Aux port can be used to troubleshoot the connectivity-related or other Router/ Switch issues.

We would be now discussing how to enable and use this port for Connecting to a Router/ Switch sing Auxiliary Port

Similar to the console port, the auxiliary port is having RJ-45 interface. To provide remote connectivity to this Router/ Switch,  this Aux Port needs to be connected to the modem, we can use standard Rollover cable for this connectivity.

At the remote end, we need a similar type of modem which would be connected to a computer at the remote modem, Both theses modems can be connected using a Telephone line.

Once all parameters are configured properly, one can initiate a dial-up connection from the remote computer too this Router/ Switch, and the user would be able to get the console connection to this device.

Configuration involves setting up loopback and loopback IP address, and mapping of ports on the modem to the router interfaces. Mainly ports 2000, and  2001 are used for this purpose. Once everything has been configured, a user at the remote location can issue the below command on the Terminal to get the console Access to the Router/ Switch if you are on a Linux Computer

telnet w.x.y.z 2000

where w.x.y.z is IP Address assigned on the Router/ Switch. Usually, it is a loopback IP Address.

If you are on a Windows machine you could either Putty Software which is available as freeware and could be downloaded from ( Alternatively if you on Pershelll on your Windows Computer you could use issue the same command as mentioned above from PowerSheel.

Here you just dialed a remote router and got attached to its auxiliary port even if the router is down (router down means its interfaces are down while the router is Switched on but it lost physical connectivity of some of its interfaces, router would be seen as down from the remote end of the interfaces which lost physical activity). Once you are done with your work you must run the command  ‘ clear line 0’ (assuming connection on line 0), to drop the console connection.

In this way, we have discussed a way to get Console Connection to the Router using Aux Port on the Router. Although this method comes to rescue in several conditions, still due to some of its limitations it is recommended as a backup option when you fail to normally connect to your Router/ Switch instead of making it default practice.

Also, read…

Download Connecting to the Switch/Router using Auxiliary Port in pdf – Click here