Re: Switch Int Shows Up When Router Int Shut

Thanks bryan , is that on your 3550 and 3560s ?
"He not busy being born is busy dying" -- Dylan

-----Original Message-----
From: Bryan Bartik <bbartik_at_ipexpert.com>

Date: Thu, 7 May 2009 18:51:30
To: CCIE Groupstudy<ccielab_at_groupstudy.com>
Subject: Re: Switch Int Shows Up When Router Int Shut

Joe,

My rack has the same behavior. I never noticed it but maybe this is
normal...never really looked at it...

R4#sho cdp ne
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater

Device ID Local Intrfce Holdtme Capability Platform Port ID
SW4 Eth 0/1 179 S I WS-C3550-2Fas 0/4
SW2 Eth 0/0 172 S I WS-C3560-2Fas 0/4
R4#

Here I shut both ports:

R4(config)#int e0/0
R4(config-if)#shut
R4(config-if)#int e0/1
R4(config-if)#shut

Now I check the status of SW4 and SW2 ports f0/4:

SW2#sho int f0/4 | inc prot
FastEthernet0/4 is up, line protocol is up (connected)
SW2#

SW4#sho int f0/4 | inc proto
FastEthernet0/4 is up, line protocol is up (connected)
SW4#

The lights are still on both sides, I pull the cable from R4 e0/0 and get
this:

SW2#
00:19:59: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/4,
changed state to down
00:20:00: %LINK-3-UPDOWN: Interface FastEthernet0/4, changed state to down
SW2#

This is different from the behavior you get when you shut the switch ports,
then you see the router port go down. Anyways, hopefully it doesn't drive
you crazy anymore.

Bryan Bartik
CCIE #23707, CCNP
Sr. Support Engineer - IPexpert, Inc.
URL: http://www.IPexpert.com

Blogs and organic groups at http://www.ccie.net
Received on Fri May 08 2009 - 03:37:24 ART