Routers – 2500 – CertSkills.com

Overview: 2500 Series Routers

These routers have been a popular option for home labs for many years, due to low used prices and a large supply in the used market. Many different models exist. The 2501 (2 serial, 1 Ethernet) is very popular, and two models in particular, the 2509 and 2511, can be useful as an access server to connect to consoles of other Cisco devices. The relatively old IOS versions make these models less popular today, but they still have many uses as platforms from which to drive traffic for testing, and as Frame Relay switches.

Feature	Fact
Popularly sold as new in years:	1993 – 1997
End-of-Sale (EOS) years:	1997 – 2007
End-of-sale for (popular) 2501	2003
Most recent mainline IOS supported	12.3
Most Recent T-train IOS supported	12.2T
Max onboard flash	16M
Max RAM	16M

All Features and Versions

Cisco Feature Navigator:
Find IOS files by Version, feature set, and platform

2500 Feature Sets Mentioned Here

IP
IP Plus
Enterprise Plus
IP/FW Plus IPSec 56

2500 Series Hardware

The 2500 series contains many different models, and several of those are useful for Cisco exam prep. Some have Ethernet interfaces, mostly with AUI connectors, which require an external transceiver. Others have Token Ring interfaces. Mostl have some number of built-in higher speed synchronous serial interfaces, and some have additional built-in slower speed (up to 128 Kbps) sync/async interfaces as well. Some of the models with sync/async ports have more port density, making these appealing as Frame Relay switch devices. Some have async serial interfaces, making these models useful as dial-up access servers: connecting these routers to the console ports of other routers and switches lets the user easily switch between the consoles of the devices.

Popular models for certification labs:

Device	Built-in sync serial	Slow speed serial	Built in LAN	Other built-in	WIC/NM slots
2501	2 (DB-60)		1 Ethernet (AUI)	None	None
2503	2 (DB-60)		1 Ethernet (AUI)	ISDN BRI	None
2509	2 (DB-60)		1 Ethernet (AUI)	8 Async (using octal cables)	None
2511	2 (DB-60)		1 Ethernet (AUI)	16 Async (using octal cables)	None
2514	2 (DB-60)		2 Ethernet (AUI)	None	None
2520	2 (DB-60)	2	1 Ethernet (AUI)	ISDN BRI	None
2522	2 (DB-60)	8	1 Ethernet (AUI)	ISDN BRI	None

Notes and Advice

The Ethernet AUI interfaces require an external transmitter/receiver (transceiver), which can cost more than the very inexpensive used 2500 router.
The serial cables need to have DB-60 connectors, which differ from the connector on the popular WIC-2T card used on other models of routers. If using 2500 series routers as well as routers with WIC-2Ts, plan to use serial crossover cables (also called back to back cables). However, you may want some with both ends as DB-60 (to connect 2500’s), some with both ends as smart serial (to connect WIC-2T’s), and some with DB-60 and smart serial on opposite ends, to connect a 2500 to a router that uses a WIC-2T.
You can use 2500’s without external transceivers to save money. When configuring, issue the no keepalivecommand under the Ethernet interface, and the router Ethernet interface will be able to come up. You cannot connect other devices to the interface, but the router will treat the interface as up/up, advertising about any connected subnets and responding to pings of the IP address on that interface.