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[RESOLVED] Trunk mode for incoming fiber from ISP for Catalyst 3560?

I had come into my work tonight so that I could do a password recovery on a Catalyst 3560G that I inherited when I took this position. I didn't have the login info for it. We wanted to replace it so I really needed to see the config but when I tried to do password recovery the syst LED went solid green and the Catalyst is unresponsive no matter what I try, I've got a terminal window open via the console port, but am getting nothing

Unfortunately this switch is primarily used to convert the incoming fiber from our ISP, then pass it along to a couple other switches. We do have a spare 3650G which I am trying to get online

I don't have a lot of experience with Cisco switches (I'm primarily a database admin) and I'm wondering if anybody can tell me do I need to configure the port as a trunk? This is a single-fiber module going into one of the 4 sfp ports. Also wondering if possibly I need to assign it our external IP address/subnet

Thanks for any assistance. I have tried to research this myself but am working on a pretty tight deadline as people will start coming into work in three hours, eek!

7 Replies 7



 - You should coordinate this question with your ISP as they must/should be able to provide correct settings for your 'local settings'.


-- ' 'Good body every evening' ' this sentence was once spotted on a logo at the entrance of a Weight Watchers Club !



who is your ISP, and what country are you in ?

You say that the problem switch connects to a couple other switches. Perhaps you can figure out part of the config of the problem switch from information from the other switches. On those switches how is the interface configured that connects to the problem switch? (trunk port/access port ?) On those switches is there a single vlan or multiple vlans? You mention an address. Is that address referenced on the other switches? If not it suggests that it was configured on the problem switch.




You have two situations. The 1º you need to do a password recovery and was unsuccessful?
The second is to get the  link interface settings from your ISP.
The first I would say that you would have to perform outside of business hours. The other solution is to obtain Link interface configurations from your ISP.


3750g you need to de-press the mode button for at least 30 seconds until it start flashing then console on to the switch 



rename flash:config.text flash:config.textold


once switch has rebooted -

copy startup-config running-config

change password



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Kind Regards

It turns out the unlabeled dead switch was the property of our provider, they had to bring another preconfigured switch out to us, and we are back up and running

They made sure to put plenty of labels on the new Catalyst 3650CX

Thanks for the update. Glad to know that it turns out that the switch was the property of the ISP and replacement was provided. 


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