The basic configuration for a Cisco 2511 access server is shown in Figure E-1. A similar configuration will work for other Cisco access servers. Cisco has excellent documentation at its web site; start by finding the correct Configuration guide.
A current maintenance contract with Cisco or a reseller is required to download software updates. This contract also includes the provision of ROMs required for flash memory upgrades. In most jurisdictions Cisco software licenses are not transferrable, so if you purcashed the access server on the second-hand market you will need to purchase a software license from Cisco or a reseller.
Figure E-1. Basic configuration for Cisco 2511 terminal server to Linux PC
interface Async1 description To Linux computer ip unnumbered Loopback0 async mode interactive no peer default ip address line 1 location To Linux PC session-timeout 30 no exec login modem InOut terminal-type vt100 special-character-bits 8 transport preferred none transport input telnet telnet break-on-ip telnet ip-on-break stopbits 1 flowcontrol hardware line vty 0 4 location Network password PASSWORD login local terminal-type vt100 transport preferred none transport output telnet
There is a port of Linux to the Cisco 2500 series of routers. At the time of writing it did did not support the asycnhronous ports on the Cisco 2511. The attractiveness of running Linux instead of running Cisco's IOS is that Linux can support SSH. At the time of writing Cisco were yet to release SSH on the Cisco 2500 series of routers, although a unofficial beta version has been seen.