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Cisco Catalyst 5509, 3500XL and Cisco 1720 router

OK to make a long story short here is my situation.  We had an external ISP/IT Support contract with a company that went BK.  I am unable to get in touch with any of their technical support staff (they all left the company).  I am not at all familiar with Cisco equipment but i have quite a bit of experience with NT and general networking.  Here is what i would like to do:

1 - I would like to be able to configure 1 10/100 port on the cisco Catalyst 5509 for network monitering (i.e. i would like it to be able to see all the packets going to and from any single port i designate on the switch).

2 - I would like to be able to configure 1 10/100 port on the cisco Catalyst 3500 XL for network monitering (i.e. i would like it to be able to see all the packets going to and from any single port i designate on the switch).

3 - We currently have 2 Cisco 1720 routers, One is from our old and now bankrupt ISP, and one is for our new ISP.  I would like to be able to download the configuration of the new ISP's 1720 and load it into the old ISP's 1720 for use as a back up.

Unfortunately i do not have passwords for any of the Cisco equipment except for the 1720 router for our new ISP.  I am not even sure if the Catalysts even have a password as i have not even attempted getting into them yet.

Thanks, Kal
1 Solution

I guess in order to do that, u need to do few things:-

To configure 1 port for Network Monitoring for Cat 5509/3500 switch,u need to make sure that ur currrent IOS software supporting a features called port mirroring. This is because in a switched environmnet, u cannot see all the traffic in the box like a hub/shared environment. What this port-mirroring do is to mirror all port in that particular switch to a management port.

I think..if i'm not mistaken , IOS 12.0 shud support that features.

3. Do u have any backup configuration from the old ISP router with u? in hardcopy or softcopy? As far as i know, we can reset the passwd in cisco router, but it will be back to factory default..and all the current config will be lost..probably other people will have a  better idea.

Hopes help
This link will provide you step-by-step password recovery for each model product. Piece of cake..


Akhmal is correct, you need to set one port on both the 5509 and the 3500 as a mirror port (SPAN port), then identify all the other ports that you want to monitor..

Try these for guidance:



For 3500:
port monitor
Use the port monitor interface configuration command to enable Switch Port Analyzer (SPAN) port monitoring on a port. Use the no form of this command to return the port to its default value.

port monitor [interface | vlan vlan-id]

no port monitor [interface | vlan vlan-id]

Syntax Description  interface
 (Optional) Module type, slot, and port number for the SPAN to be enabled. The interface specified is the port to be monitored.
vlan vlan-id
 (Optional) ID of the VLAN to be monitored. Valid IDs are from 1 to 1000; do not enter leading zeroes. A monitor port must be a member of the same VLAN as the port monitored.


Port does not monitor any other ports.

KallikAuthor Commented:
thanks, the password recovery procedures were invaluable

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