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Cat 2950 with no ip address

I have a switch at a remote location that has been in place for sometime that for some reason was never assigned an ip address. CDP is enabled, it is directly connected to a router. Here's the show cdp nei detail output...

------------------------- Device ID: M-Sub-Switch Entry address(es): Platform: cisco WS-C2950C-24, Capabilities: Switch IGMP Interface: FastEthernet0/0, Port ID (outgoing port): FastEthernet0/25 Holdtime : 178 sec

Version : Cisco Internetwork Operating System Software IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(9)EA1, RELEASE SOFTWARE ( fc1) Copyright (c) 1986-2002 by cisco Systems, Inc. Compiled Wed 24-Apr-02 06:57 by antonino

advertisement version: 2 Protocol Hello: OUI=0x00000C, Protocol ID=0x0112; payload len=27, value=0000000

0FFFFFFFF010221FF000000000000000AB72F7C80FF0000 VTP Management Domain: '' Duplex: full

-------------------------

So it looks like it has been assigned a hostname, so someone has been in the switch at least once.

Is there a way to assign this switch an address via the router it is connected to?

Reply to
rfield
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It may not be possible, but you can try the following:

On the router that is connected to it, look at the router's ARP cache for a Cisco MAC Address, then on the same router use the ARP command to add a static entry for the switch using a spare valid IP for that subnet, i.e.

conf t arp 192.168.1.100 000e.84af.5b77

now you can try to ping it from the router, if that works try a telnet. if that doesn't work try both HTTP and SNMP from a PC in case they are enabled.

Good luck,

Martin

Reply to
Martin Kayes

On 02.08.2005 23:20 Martin Kayes wrote

That doesn't work. You have to assign an IP address to the remote device to make an IP connection work.

If your "trick" would work it would be very easy to break into any computer I know an MAC address of.

Arnold

Reply to
Arnold Nipper

How do you figure? Authentication/authorization is different than IP access. Just cause you could establish a connection, doesn't mean that you can log in. Actually, there are devices that use this technology to help you get an ip without having a console cable - one example that comes to mind is Lantronix terminal servers.

Having this "trick" does nothing to help you break into a machine that you know the mac address of. Most of them have an ip address anyway. There, you don't even need the mac - just hack away. You still need authentication/authorization.

This may not work with Cisco routers/switches, but it is something that other vendors may use.

Jim

Reply to
Scooby

Just another idea:

If you can make someone else to connect a console cable between the aux port of the router and the console port of the switch, you can jump to the switch from the router doing a reverse telnet to the tcp port associated to the Aux port in the router.

I have done this in the past when a 2950 has turned down their management vlan.

Regards, A friend from Santiago, Chile

Reply to
kar_uso

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