ISR4451 router configures bridge group under EI interface

[Translator]

The ISR4451 router is based on the XE system, and it is not possible to configure a bridge group under the interface in this system. I have found the configuration related to the bridge domain based on the XE system (only related to Ethernet interfaces). Currently, I have successfully configured the bridge domain under the Ethernet interface, but how do I add the corresponding bridge domain under the E1 interface? I really can't find the relevant commands. Seeking guidance from experts!!!

[Giuseppe Larosa]

Hello ,

you cannot bridge between an ethernet interface and a sync serial E1 interface.

it is possible to bridge between serial interfaces using the same encapsulation but not between LAN and serial

Between LAN and serial you need to route routable traffic like IPv4.

Hope to help

Giuseppe

[Translator · Accepted solution]

We used the previous model 2811 router is the IOS system platform, can be configured under the EI interface Bridge-Group group, but also can realize the function;

ISR4451 is based on IOS XE platform, can we downgrade the system to IOS system to achieve? Is that OK?

[Giuseppe Larosa]

Hello,

you cannot downgrade the ISR 4451 to use old IOS images, the router works only with IOS XE.

And yes the bridge-groups in IOS was different .

Now in IOS XE we have bridge domains and BDIs as Layer3 interfaces .

As an alternative to provide a L2 point to service transport service between two routers over an IP routed internetwork you can use L2TPv3

see the following chapter of configuration guide

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/wan_lserv/configuration/xe-16-5/wan-lserv-xe-16-5-book/wan-l2-tun-pro-v3-xe.html?dtid=osscdc000283

there are some licensing requirements for using the feature.

Smart licensing has been introduced in IOS XE 16.10 and later so your router may use smart licensing.

Hope to help

Giuseppe

[Translator]

Hello, here is the network topology diagram. The control devices and protection devices of our two stations communicate with each other, and do not interfere with each other. And they send and receive data to each other through UDP broadcast.

The internal interfaces of the two routers are divided into two bridge domains for the control device and the protection device respectively, and the external two EI interfaces adopt the L2TPV3 channel mode. Is this feasible?

If so, how do I correlate two bridge domains with two L2TPV3 channels one by one?

[Giuseppe Larosa]

Hello,

>> If so, how do I correlate two bridge domains with two L2TPV3 channels one by one?

yes you will use two different subinterfaces that use a different VLAN ID for each L2TPv3 xconnect

Hope to help

Giuseppe

[Translator]

Hello, I don't understand. Are the two different sub-interfaces that you're talking about: Serial0/0/0:0 and Serial0/1/0:0? Which scenario example of a link is used in this way? How are two L2TPV3 channels associated with two bridge domains, and is there a corresponding configuration script? Please!

[Translator]

Under each router two groups of interfaces are directly connected to the terminal equipment, the interfaces are all three-layer interfaces, does not support the division into two-layer interfaces;

And the bridge domain joined under each set of interfaces is encapsulation  untagged without VLAN Related Information; Configure L2TPV3 in the direction of both routers and, as you say, cannot encapsulation under both subinterfaces port-channel vlan ID, so it is impossible to distinguish whether two bridge domains are bound to two L2TPV3 channels;

How can I distinguish between two bridge domains bound to two L2TPV3 channels for this scenario?

[Giuseppe Larosa]

Hello ,

I'm referring to something like the following:

SUMMARY STEPS

1. enable
2. configure terminal
3. interface ge0/0.10
4. encapsulation dotq 10
5. xconnect peer-ip-address encapsulation l2tpv3 1010 pw-class pippo
   

  int gi0/0.20

enc dot1q 20

xconnect <peer-address> encapsulation l2tpv3 1020 pw-class pippo

1. end

and so on each subif will use a different VC ID like 1010 , 1020 and so on this allows to the remote peer to understand where to deliver received frames  ( because they travel untagged within the payload of L2TPv3 packet)

see

https://www.cisco.com/c/en/us/td/docs/routers/ios/config/17-x/lan-wan/b-lan-wan/m_wan-l2-tun-pro-v3-xe.html?dtid=osscdc000283#GUID-E31AC966-122A-4129-8D0E-A12E7EB9D88F

The serial interfaces need to be reconfigured with an IP addres they are not part of the xconnect , the xconnect is configured on the LAN side under a physical ge interface in my example I used gi0/0 in your case use the name of the gigainterface you are going to use to connect to the VLANs to be carried on L2TPv3.

the subinterfaces with the xconnect command cannot have an IP address on it.

Hope to help

Giuseppe

[Translator]

Hello, for the attached network topology diagram, if my router two groups of internal network ports are joined by two bridge domains. As you say, you need to configure xconnect-related commands under the router's intranet interfaces, but they are all three-layer interfaces and do not support layer-two switching.

So, how do I configure two serial ports of my router, two routers are connected through two serial ports. Each serial port channel needs to pass the data of the terminal equipment under two bridge domains.

Can you give me a complete configuration script for my network topology diagram, thank you!

[Translator]

network topology diagram