07-03-2009 05:18 AM - edited 03-04-2019 05:19 AM
Hi all
I have a 2800 router connected to a switch which is conifgured as a trunk port to carry 2 vlans. We want one of the vlans to be passed onto another switch through the router as we are only allowed a single connection on the first switch. The router has a 4 port etherswitch module which we have connected to the second switch. Vlan 115 is an internet Vlan that will terminate on a firewall.
Have I got the following correctly configured as I am not sure why I need "bridge irb" when effectively we only want to bridge but it doesn't seem to work with out it:
Bridge irb
Bridge 15 protocol ieee
Int g0/1
No ip address
No shutdown
Int g0/1.115
Encapsulation dot1q 115
Bridge-group 115
Int g0/1.2033
Encapsulation dot1q 2033
Ip address 10.250.254.254 255.255.255.252
Int g0/1.100
Encapsulation dot1q 100 native
No ip address
Vlan 115
No ip address
Bridge-group 115
Int fa0/0/0
Switchport access vlan 115
Solved! Go to Solution.
07-06-2009 06:34 AM
In my opinion - it's not the best way of doing things, but as long as it works!
;o)
07-03-2009 07:48 AM
Integrated Routing and Bridging, allows you to route a given protocol between routed interfaces and bridge groups within a single switch router
http://www.cisco.com/en/US/tech/tk389/tk815/technologies_tech_note09186a0080094663.shtml
HTH>
07-03-2009 08:43 AM
You have an EtherSwitch module which supports internal Vlan configuration and there is no need for subinterfaces.
The following URL will provide information on how to configure Vlans on the router:
Once the Vlans are configured, you can configure a switchport as trunk facing the switch carrying the multiple Vlans and as access facing the switch with Vlan 115.
If you want to have a Layer3 representation of any of the L2 Vlans, you can create a SVI.
Your configuration would look like this:
!Configure L2 Vlans
vlan database
vlan 115
vlan 2033
vlan 100
exit
!
!Configure Switchports
default interface g0/1
default interface f0/0/0
!
interface f0/0/0
switchport access vlan 115
interface f0/0/1
switchport encapsulation trunk dot1q
switchport mode trunk
!
!
no bridge irb
!
!
interface Vlan 2033
ip address 10.250.254.254 255.255.255.252
HTH,
__
Edison.
07-05-2009 03:54 PM
Hi Ed
Thanks for the response, however, I am using the onboard gig port to trunk as the etherswitch ports have limited QoS support and we need to do Traffic shaping.
So I am pretty sure I need to bridge.
07-05-2009 11:48 PM
You do not need to bridge to perform QoS.
07-06-2009 03:04 AM
I need to bridge becuase I have 2 vlans and one of those vlans I want to connect to a different device whilst the other will be routed.
07-06-2009 03:27 AM
If you have a switch that is vlan capable - then you do not need to place an interface of the router into a bridged port. You just connect the other device directly to the switch in the relevant vlan. There is no need for the router to be involved for un-routed traffic.
07-06-2009 03:54 AM
We only have a single connection available on the switch.
07-06-2009 04:03 AM
Then for this fudge - you need irb.
07-06-2009 06:23 AM
Thanks
Was my config ok then?
Things like having to create an SVI with no ip address etc?
07-06-2009 06:34 AM
In my opinion - it's not the best way of doing things, but as long as it works!
;o)
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