04-25-2013 01:41 PM - edited 03-07-2019 01:02 PM
Hello all,
I've run into an issue with this type switch, and hoping that you can provide some guidance/advice.
I've a 2611xm router connected to a C2924-XL switch ((C2900XL-C3H2S-M), Version 12.0(5)WC17)
Basically i configured the router as a RoTS with two sub interfaces setup with encapsulation dot1q as per below:
interface FastEthernet0/0
description TO MODEM
ip address <external IP and mask removed>
ip nat outside
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 192.168.31.254 255.255.255.0
ip nat inside
ip tcp adjust-mss 1452
duplex auto
speed auto
!
interface FastEthernet0/1.10
encapsulation dot1q 10
ip address 192.168.10.254 255.255.255.0
ip access-group WCS_USER in
no ip redirects
ip nat inside
ip tcp adjust-mss 1452
!
interface FastEthernet0/1.20
encapsulation dot1q 20
ip address 192.168.20.254 255.255.255.0
ip access-group GUEST_USER in
no ip redirects
ip nat inside
ip tcp adjust-mss 1452
!
-----------------
on the switch, i issued the following command on port fa0/4 (connected to router)
switchport mode trunk
and as soon as i pressed enter, the switch became unresponsive, as in, it wont return pings, or acknowledge telnet access and keeps timing out. it does show up on the router when show cdp neighbor command is issued.
unfortunately, i cannot access the switch directly, as its a remote switch.
pleaes note that prior to all this, the switch was working perfectly OK.
any tips are highly appreciated.
\regards
Solved! Go to Solution.
04-25-2013 02:42 PM
switchport mode trunk
Is this the only command? Did you also include "switchport trunk encapsulation dot1q"?
04-25-2013 02:04 PM
May I know on what port on router the switch is connected to ? On the router can you see that port is UP ?
Sent from Cisco Technical Support iPhone App
04-25-2013 02:20 PM
Yes, sorry for missing that critical piece.
The switch is connected to router's port fa0/1 port, and
The router is connected to switch's port fa0/4
All are up and up
Router#sh ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0
FastEthernet0/1 192.168.31.254 YES NVRAM up up
FastEthernet0/1.10 192.168.10.254 YES NVRAM up up
FastEthernet0/1.20 192.168.20.254 YES NVRAM up up
NVI0 unassigned NO unset up up
04-25-2013 02:42 PM
switchport mode trunk
Is this the only command? Did you also include "switchport trunk encapsulation dot1q"?
04-25-2013 02:46 PM
Unfortunately, I did NOT issue that command, prior to the command "switchport mode trunk".
and i think that is the cause of this issue.
i think one possible way of solving this would be to ask the local person there to just plug the router into another open port on the switch, then access the switch and issue the command "switchport trunk encapsulation dot1q" on the original port fa0/4, and then reconnect, the router back to that port fa0/4.
04-25-2013 03:03 PM
I'm not sure if this'll work, but change the router's trunk to "ISL" instead of "dot1q".
04-25-2013 03:50 PM
Leolaohoo, i tried changing the encapsulation to ISL, but that didnt work either. Its probably that other missed command on the switch.
04-26-2013 03:29 AM
Just a quick update. The issue was resolved after inserting the 'switchport trunk encapsulation dot1q' command on port fa0/4 (connected to router).
I basically their local user at the remote end, to switch the cable from port fa0/4 to any other open port on the switch (in this case it turned out to be fa0/7). Once that was done, i was able to access the switch, update the switchport setting. connect the router back to port fa0/4. and all is well.
thanks everyone that responded.
best regards.
04-28-2013 03:26 PM
May I request if you can mark this thread as "Answered"?
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