Q: I have a Cisco 2950, which was always back and forth at work, so I saved. I try tog et on my home network setup and I am surprised. It is a 12-port switch.
My setup is Cable Modem-Router SMC u003e (handling DHCP)-2950-Cisco u003e u003e PCs
Problem is, at any time of the Cisco switch is turned on and connected, it just kills the rest my network and everything goes to crap. At work we just have a cable plugged into the wall jack to port 1 on the switch and a PC connected to a different port and everything was fine. No idea why it is not any more.
I him work reset the settings manually and is not necessary to actually program something because I just want it to work like any ordinary old hub / switch would.
I tried a crossover cable and regular cable and no work. Then I have a PC directly connected to the SMC router, it still gets crap for the internet and the Cisco switch is connected. Once I pull the plug, start everything works fine. Seems odd to the me.
Also shouoldnt be hardware related as the switch was hardly ever used and is basically brand new.
Any ideas?
Thanks!
Thanks.
Re:IIRC, the serial cable I purchased everytime I needed a network console cable was actually a DB9 mouse extension cable for a couple bucks. They were always cheaper because they didn't have the network name on them.
Re:heh, thanks.
I've never touched a 2950. I just "assumed" all their switches do L3 nowadays.
Re:2950's don't do L3
reset the config. If you can't get enabled mode, then reset from bootup (hold the buttom, flash_init, del flash:\config.txt, blah blah blah)
Re:If the switch was reset to factory then it will pick up a DHCP address (although I dont' know how you cleared the configruation if you don't know how to console into it…you need a console or telnet to do it), just check the DHCP table and match up the MAC address of the switch. From there you can telnet into the switch.
If you want to truly reset the configuration…
write erase
reload
The only thing of if you plug the switch in and you lose communication, that makes me thing of a loop somewhere. make sure you have no loops.
Also, you can't really just take a cisco switch and not do any configuration. There are certain things that need to be done. Mainly spanning-tree related.
Are you saying that if you just plug the 2950 with a single connection only you have communication problems? I don't know if the 2950 does layer3 switching, but it could be proxy arping for your clients if you have any routing enabled on it. post the configuration of the switch by telneting into it. Or on the off shoot it has the same address as your router.
Re:Hmm. Don't think I have the cable needed to console in I guess. I'll have to see if someone has one at work. And yes, this woudl be in the basement so the loud fan and such wouldn't be any big deal. This was more of just a thing to do for the coolness factor so I'll probably just put it on the back burner.
But thanks for all the info.
Re:For the console port you need a rolled cable going from the serial port of your PC to the console port of the switch.
No extra software is needed besides hyper terminal or any other software you use of telnet/serial connections.
Usually you want to hardcode uplink ports on both sides to be sure everything matches w/o duplex or speed mismatch.
The switch is loud and I wouldn't want it in my home (unless you set it up in your basement or lab purpose.)
Re:Originally posted by: guy
console in, check the counters (reset and track) on your uplink. I would guess a duplex mismatch on your uplink port. Keep you console connected and it will usually tell you the problem.
Duplex mismatches may be said on the console, but you can look for errors on the counters for the interface (show int fa0/1)
I've never actually consoled into a switch before. Do I need their software for that? And do I just plug a normal Cat5 cable from my laptop's jack to the COnsole jack and that's it?
Re:console in, check the counters (reset and track) on your uplink. I would guess a duplex mismatch on your uplink port. Keep you console connected and it will usually tell you the problem.
Duplex mismatches may be said on the console, but you can look for errors on the counters for the interface (show int fa0/1)
Re:Here is a link to the deployment guide from Cisco for how to set up the switch:
http://www.cisco.com/en/US/products/sw/…ser_guide_chapter09186a008015b87b.html (http://www.cisco.com/en/US/products/sw/netmgtsw/ps4975/products_user_guide_chapter09186a008015b87b.html)
Re:I ran the Quick Setup thing and gave it an IP on my normal range and put in the gateway of my main router. That's all it asked for. Plugged it in and everything just went to crap. I slapped in my 9port Netgear Hub and that's working just fine. I guess I'll just play with this thing whenever I find some freetime. heh.
Re:Does the switch have an IP? Could it have the gateway IP for the management interface?
That right there would bork the internet bad.
Maybe it has some different subnet for the management interface, and that is somehow causing the problem.
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