?
Solved

configuring etherchannel between switches

Posted on 2008-10-07
5
Medium Priority
?
1,394 Views
Last Modified: 2012-05-05
We have 2 floors at one of our locations.  The main floor is where the core 3750 switch with 48 GB ports is and the other floor has 4 3560s, each with 4 GBIC ports.  One of the 3560 is already set up for etherchannel to the 3750.  I need to configure the other 3 switches (which already have 1 connection to the 3750) to use the second GBIC port and enable etherchannel.  

I'm sure this is not that difficult to set up but since I have never done it before I figured I'd check with the experts.  


Here's the pertinent parts of the configs for the routers that are currently working (at least I think...let me know if you need more information)


3750 config (Core Switch)

vlan 7
 name Management

interface Port-channel5
 description Uplink to 3560-48-9th-floor-2
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk

interface GigabitEthernet1/0/39
 description Crossconnect to 9th floor Switch II GIG port I
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk
 mls qos trust cos
 channel-group 5 mode on


interface GigabitEthernet2/0/39
 description Crossconnect to 9th floor Switch II GIG port II
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk
 mls qos trust cos
 channel-group 5 mode on

interface Vlan7
 ip address 192.168.157.1 255.255.255.0

end



2560 wih etherchannel configured and working

vlan 7,10,20-21,40

interface Port-channel1
 description uplink to Core
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk

interface GigabitEthernet0/1
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk
 speed 1000
 duplex full
 mls qos trust cos
 channel-group 1 mode on
!
interface GigabitEthernet0/2
 description Crossconnect to 8th floor wwc-4948g port 39
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk
 speed 1000
 duplex full
 mls qos trust cos
 channel-group 1 mode on

interface Vlan7
 ip address 192.168.157.11 255.255.255.0

end


3560 not configured for etherchannel yet

interface GigabitEthernet0/1
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk
 priority-queue out
 mls qos trust cos
!
interface GigabitEthernet0/2
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk
 priority-queue out
 mls qos trust cos

end



so, there's nothing about port-channel in there...i assume i'm going to have to add the following

interface Port-channel1
 description uplink to Core
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 7
 switchport mode trunk


as well as this to each GBIC port

speed 1000
duplex full
channel-group 1 mode on


Is that it?  

Also, I haven't installed the GBICs yet.  Can that be done while the switch is in production?  Should I configure the ports first before plugging in the GBIC/the network cable?  I imagine if i plug in the cable before configuring Etherchannel I'm going to have some spanning-tree problems.  

I know this is long...thanks for your time and help in advance.
0
Comment
Question by:shanna1017
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
5 Comments
 
LVL 50

Expert Comment

by:Don Johnston
ID: 22664492
The port channel interface will be created automatically by the IOS when you issue the "channel-group" command on the physical interfaces.

Personally, when going between Cisco switches, I prefer "desirable" mode.


0
 

Author Comment

by:shanna1017
ID: 22664835
ok so i just need to add the channel-group commands to each interface and I should be good to go?  

what about this questions?

"Also, I haven't installed the GBICs yet.  Can that be done while the switch is in production?  Should I configure the ports first before plugging in the GBIC/the network cable?  I imagine if i plug in the cable before configuring Etherchannel I'm going to have some spanning-tree problems.  "

I know this is long...thanks for your time and help in advance.
0
 
LVL 50

Accepted Solution

by:
Don Johnston earned 2000 total points
ID: 22664898
Yes. The channel-group command is done on each physical interface.

I would install the GBICs, shutdown the interfaces, connect the cables, configure the interfaces and then "no shut" them.

And if it were me, I'd do it during a maintenance window. You know, anything that can go wrong... :-)
0
 

Author Comment

by:shanna1017
ID: 22664902
cool.  thanks a bunch donjohnston!

assuming everything works as explained I will award you the points.
0
 
LVL 12

Expert Comment

by:Pugglewuggle
ID: 22666192
One other thing to note - if you are trunking VLANs over the etherchannel - make sure you don't just allow a fre VLANs - allow them ALL if it is not a problem. This will prevent problems later if you need to add more.
Let me explain - when adding VLANs to a trunked etherchannel port, you MUST configure the VLANs on all physical ports AND in the etherchannel commands or the etherchannel will go down and you will have to make a trip to the device to manually add the configuration to the rest of the interfaces.
Save yourself the trouble and just trunk all VLANs now instead of possibly taking a whole segment of your network that connects through the etherchannel offline later. If this is a main switch, you (or a colleague) can take your whole company offline BY ACCIDENT for whatever time it takes you to get to the switch and fix it through the console cable.
Just a bit of advice learned the hard way. I hope this saves you the same trouble!
Cheers!
0

Featured Post

Get real performance insights from real users

Key features:
- Total Pages Views and Load times
- Top Pages Viewed and Load Times
- Real Time Site Page Build Performance
- Users’ Browser and Platform Performance
- Geographic User Breakdown
- And more

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This tutorial will go through the steps required to write a script that will back up the configuration settings of a HP-ProCurve switch. You will need to get the following things to follow this tutorial: Telnet Scripting Tool e.g. TST10.exe …
This article will show how Aten was able to supply easy management and control for Artear's video walls and wide range display configurations of their newsroom.
This is my first video review of Microsoft Bookings, I will be doing a part two with a bit more information, but wanted to get this out to you folks.
Have you created a query with information for a calendar? ... and then, abra-cadabra, the calendar is done?! I am going to show you how to make that happen. Visualize your data!  ... really see it To use the code to create a calendar from a q…

752 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question