Hi,
You can configure Etherchannel to bundle the ports.
It is possible to create a port-channel on 2921 to bundle the interfaces on motherboard, here are few points which should be considered :
1. Negotiation protocols like PAgP and LACP are not supported on onboard ports. You have to set it up manually with "mode ON"
2. Etherchannel could not be formed with the mix of On board Gig, ES3/2 or HWIC ports in ISR G2
For the Other End if you are using a Stack Switch, it is possible to bundle the ports cross stack. You could check the following URL’s :
http://www.cisco.com/en/US/products/hw/switches/ps5023/products_configuration_example09186a00806cb982.shtml
https://supportforums.cisco.com/docs/DOC-1901
Following is the sample configuration example which tested few days back for one of my customers on 2911 which is also an ISRG2 router and 3560 switch and was able to ping end to end from both the devices.
<2911>
BGL.I.01-2900-1#sh run int po1
Building configuration...
Current configuration : 68 bytes
!
interface Port-channel1
ip address 10.10.10.2 255.255.255.0
end
BGL.I.01-2900-1#sh run int gi0/2
Building configuration...
Current configuration : 93 bytes
!
interface GigabitEthernet0/2
no ip address
duplex auto
speed auto
channel-group 1
end
<3560>
BGL.I.08-3500-6#sh run int po1
Building configuration...
Current configuration : 83 bytes
!
interface Port-channel1
no switchport
ip address 10.10.10.1 255.255.255.0
end
BGL.I.08-3500-6#sh run int fa0/1
Building configuration...
Current configuration : 88 bytes
!
interface FastEthernet0/1
no switchport
no ip address
channel-group 1 mode on
end
<>
Also on Router/Multilayer SW's an ip from the same subnet cannot be assigned on the multiple interfaces, so if you need to have redundant connections - then etherchannel is the best option.
- HTH
Rahul
