Redundant Controlling Bridges Configuration Example

The following example shows how to use full automation, partial automation, or manual configuration to set up a redundant controlling bridge (CB) topology with three attached bridge port extenders (BPEs) in a two-tier structure (see Redundant CBs with Two-Tier BPEs Topology).

For more information about redundant CBs, see Redundant Controlling Bridges.

Connect the CBs.
Decide whether to use full or partial automation, or manual setup to configure the Extended Edge Switching topology:
- For full automation, go to Full Automation Configuration Example.
- For partial automation, go to Partial Automation Configuration Example.
- For manual setup, continue with the rest of this procedure.

Create the peer relationship between the CBs on CB1:

enable sharing 1:22 group 1:22,1:26 lacp
create vlan isc tag 100
configure isc ipaddress 1.1.1.1/24
configure isc add port 1:22 tagged
create mlag peer vpex_peer
configure mlag peer vpex_peer ipaddress 1.1.1.2

Create the peer relationship between the CBs on CB2:

enable sharing 1:22 group 1:22,1:26 lacp
create vlan isc tag 100
configure isc ipaddress 1.1.1.2/24
configure isc add port 1:22 tagged
create mlag peer vpex_peer
configure mlag peer vpex_peer ipaddress 1.1.1.1

Start MLAG orchestration on CB1:
```
start orchestration mlag vpex_peer
```
Note
The CLI prompt changes to inform you that you are in orchestration mode.

Using orchestration mode enforces that all configuration commands are now checkpointed to the MLAG peer switch.

Create LAGs between CB and first-tier BPEs by substituting the following commands in step 3:

Slot-1 VPEX 5520.1 # enable sharing 1:10 group 1:10 lacp
Slot-1 VPEX 5520.2 # enable sharing 1:20 group 1:20 lacp

Set up the rest of the MLAG by executing the commands in the Manual Configuration Example, inserting the following commands between step 2 and 3:
```
enable mlag port 1:10 peer vpex_peer id 101
enable mlag port 1:20 peer vpex_peer id 102
```
When LACP shared ports are configured as MLAG ports, a LAG ID change after MLAG peer reboot may result in MLAG ports being removed and re-added to the aggregator.
To avoid the MLAG port flap, configure a common LACP MAC in both MLAG peers:
```
configure mlag peer peer_name lacp-mac lacp_mac_address
```
If the ISC port belongs to a higher port number and the MLAG port comes up before the ISC port on reboot/failover, then it might create a short loop.
To avoid the short loop, configure the reload delay timer for the MLAG ports to bring up the MLAG port with some delay:
```
configure mlag ports reload-delay <time>
enable mlag port reload-delay
```
The ISC port now comes up before MLAG port:
Enable MLAG port isolation to prevent packet forwarding over the ISC before the blocking filters are installed:
```
configure mlag ports link-up-isolation on
```

For MLAG best practices with VPEX, see the following article: MLAG best practices with VPEX