USB serial adapter on Red Hat Enterprise Linux 5

Last modified: Mar. 6, 2008

1 - Summary
2 - Software installation
3 - Test USB serial adapter
4 - Connect to router

1 - Summary

This guide explains how to install a USB serial adapter in Red Hat Enterprise
Linux 5. It also explains how to connect to a device like a router over a
serial connection. As an example we will connect to a Cisco router.

2 - Software installation

We will be using cu to connect to the Cisco router so we need to make sure
that the uucp package is installed.

# rpm -qa | grep uucp

3 - Test USB serial adapter

After you reboot log in with a normal user account. Plug in the USB serial
adapter into the computer and check to make sure it was detetectd properly.

Run dmesg and you should a line similiar to this at the end.

# dmesg
usb 1-1: new full speed USB device using uhci_hcd and address 2
usb 1-1: configuration #1 chosen from 1 choice
usbcore: registered new driver usbserial
drivers/usb/serial/usb-serial.c: USB Serial support registered for generic
usbcore: registered new driver usbserial_generic
drivers/usb/serial/usb-serial.c: USB Serial Driver core
drivers/usb/serial/usb-serial.c: USB Serial support registered for pl2303
pl2303 1-1:1.0: pl2303 converter detected
usb 1-1: pl2303 converter now attached to ttyUSB0
usbcore: registered new driver pl2303
drivers/usb/serial/pl2303.c: Prolific PL2303 USB to serial adaptor driver

Find what the actual device is listed as.

# ls -l /dev/ttyUSB*
crw-rw---- 1 root uucp 188, 0 Mar  6 19:35 /dev/ttyUSB0

In our example it's listed as /dev/ttyUSB0

4 - Connect to router

Connect a serial cable from the USB serial adapter to the console port on
the back of the Cisco router. Switch users to become root, type the following
and press Enter to connect.

# cu -l /dev/ttyUSB0 -s 9600

User Access Verification

Username: xxx
Password: xxx
Welcome to!

When you are done type exit.


router con0 is now available
Press RETURN to get started.

Type '~.' to exit. Press 'Shift+~' then period.


Last modified: Thu Jan 1 00:00:00 1970 UTC
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