09-26-2012 04:24 PM - edited 03-07-2019 09:08 AM
Hey!
I was attempting to implement etherchannel on my device. When I configured the two trunk interfaces into the channel group I lost connectivity. this is the last thing I saw:
RowA-Rack8-en1-slot8#conf t
Enter configuration commands, one per line. End with CNTL/Z.
RowA-Rack8-en1-slot8(config)#int po1
RowA-Rack8-en1-slot8(config-if)#descrip PO36 3750_RowA
RowA-Rack8-en1-slot8(config-if)#$trunk allowed vlan 152,160,424,426,439,508
RowA-Rack8-en1-slot8(config-if)#switchport mode trunk
RowA-Rack8-en1-slot8(config-if)#switch no
RowA-Rack8-en1-slot8(config-if)#exit
RowA-Rack8-en1-slot8(config)#int ran g0/21 - 22
RowA-Rack8-en1-slot8(config-if-range)#channel-group 1 mode active
Connection to host lost.
The two interfaces were already configured and I was just adding the channel-group statement.
The trunks appear okay from the perspective of the uplink:
Gi4/0/24 172.16.201.233 Row connected trunk a-full a-1000 10/100/1000BaseTX
Gi1/0/8 172.16.201.233 Row connected trunk a-full a-1000 10/100/1000BaseTX
Gi1/0/8 152,160,424,426,439,508
Gi4/0/24 152,160,424,426,439,508
interface Port-channel36
description port 1/0/8 and 4/0/24 -- RowA-Rack8-en1-slot8
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 152,160,424,426,439,508
switchport mode trunk interface Port-channel36
end
Is this down or have I just lost connectivity.
What the heck did I do.
Kat
09-26-2012 04:32 PM
Kat
Firstly with L2 etherchannel you should not configure po1. When you add the channel-group 1 mode active to the interfaces po1 should be automatically created for you. You then can add config lines under po1.
That said, how are the ports on the other switch configured ?
Can you also post "sh etherchannel summary" off the switch.
Jon
09-26-2012 04:40 PM
Well I have lost the device and cannot get back into it.
This is how other devices are configured and working:
interface Port-channel1
description etherchannel to 3750_RowA
switchport trunk allowed vlan 152,423,424,456,508
switchport mode trunk
switchport nonegotiate
!
interface GigabitEthernet0/21
description connection to 3750_ROWA
switchport trunk allowed vlan 152,423,424,456,508
switchport mode trunk
switchport nonegotiate
channel-group 1 mode active
!
interface GigabitEthernet0/22
description connection to 3750_ROWA
switchport trunk allowed vlan 152,423,424,456,508
switchport mode trunk
switchport nonegotiate
channel-group 1 mode active
!
This is the show etherchannel summary from the other side
36 Po36(SD) LACP Gi1/0/8(I) Gi4/0/24(I)
09-26-2012 04:44 PM
It is showing it down. Perhaps you could try reverting to a single trunk link on both sides then compare configs to make sure they are exactly the same on both switches and then try bringing back up.
Jon
09-26-2012 04:48 PM
Something is wrong with the config
the summary shows po36 while the config shows po1
09-26-2012 04:50 PM
Reza
I think po36 is from the other end of the connection.
Jon
09-26-2012 07:18 PM
Hi Jon,
How is everything going?
So, one side is po36 and the other side is 1?
Reza
09-26-2012 07:35 PM
Hi Reza
Not bad, answering a few more questions recently. Hope everythings good with you ?
Yes i think Kat has lost connectivity to the actual switch with po1 on it and po36 is the other end.
Jon
09-26-2012 07:45 PM
Everything is going good Jon. Had a chance lately to work with Nexus series switches. Nice devices, and I like the Nexus OS much more then native IOS.
Reza
09-27-2012 07:22 AM
Thank you for all these lovely emails! omg you're killing me.
I had to have the device rebooted because it is remote to me. I did lose server connectivity not just management.
The discrepancy was in the vlan allowances.
Thanks Jon for the tip on not having to build out the Po interface.
Kat
CORRECT ANSWER
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