Catalyst 500 Express Port Issue

[hutton]

Hi there,

We have inherited a small network, 2 x 24 port Catalyst 500 Express switches with most ports utilised.

One of the ports has been shared for some time using a small switch in the office, two PCs connect to the local switch which then connects down to the main one.  Problem is the PCs are disconnecting continously and we do not know the details of the switch to login to manage it.  On the switch itself we can see the port flashes green for a second then flashes amber.  All other network connectivity is ok.

We have tried the following:

- Changed auto negotiate on PC NICS to 100Mbps/full and 10Mbps/full

- Tried other ports

- Tried a splitter

- To eliminate cabling issue tried the same setup in the computer room, attaching switch directly to the port, same issue

With the last test in mind, it makes sense to login to the switch to see what it can see.  I assume settings need to be changed to allow more than one MAC used or something along those lines?  Or maybe another problem.

The issue is we do not know the management IP address of the switches.  We have tried the two default (10.0.0.1 and 169.254.0.1) and used the Cisco Network Assistant to scan the subnet without success.  Also tried 192.168.1.0 subnet just in case.

Is there any way of obtaining these details? I realise we don't have login IDs either.  Unfortunately there is no way of dicussing the switch with previous IT support company.

Would we need to go as far as resettting the switch to factory defaults (disconnecting the cables and possible after-effects are something we'd like to avoid if possible).

Any help will be much appreciated.

Hutton.

[sarbjeet-dhillon]

Hi,

Do the PC's obtain a dhcp address from the switch?

SD

[hutton]

Hi SD,

No, they used to obtain DHCP address from a server.

I forgot to mention we configured static IP addresses on the PCs during troubleshooting, which they still have...

Regards,

Hutton.

[sarbjeet-dhillon · Accepted solution]

OK, with the limited information, the LED condition sounds to me like the link is faulty.

I suggest you replace the cables, making sure you use a crossover between the switches.

SD

[hutton]

Hi, thank you.

If it helps build a better picture - a single device on a port it works, if >1 then the amber flashing and disconnections occur.

Also new cabdling was tried, directly attached to the switch and the same issue occured.

Hence we thought the next step would be to connect to the management/config to see what's happening.  Would this make sense?  Is it possible to determine the management IP address without resetting to factory defaults?  Regards.

[hutton]

Hi SD,

You're spot on - I just retried and new cables directly connected are working.  We'd seen amber lights when connecting previously as the client connects.  Thank you.

Will update when the cables are replaced to confirm.

[hutton]

The link was ok, the issue was the power unit for the switch in the back office.  Thanks and regards.