Multiple Domains Using Layer 2 and Layer 3 Redundancy

The example shown in the following figure illustrates an ESRP configuration that has multiple domains using Layer 2 and Layer 3 redundancy.

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Multiple ESRP Domains Using Layer 2 and Layer 3 Redundancy
../Graphics/EX_098.svg

This example builds on the previous example. It has the following features:

  • An additional VLAN, Engineering, is added that uses Layer 2 redundancy.

  • VLAN Sales uses three active links to each ESRP switch.

  • VLAN Engineering has two active links to each ESRP switch.

  • One of the edge devices carries traffic for both VLANs.

  • The link between the third edge device and the first ESRP switch uses 802.1Q tagging to carry traffic from both VLANs on one link. The ESRP switch counts the link active for each VLAN.

  • The second ESRP switch has a separate physical port for each VLAN connected to the third edge switch.

In this example, the ESRP switches are configured such that VLAN Sales normally uses the first ESRP switch and VLAN Engineering normally uses the second ESRP switch. This is accomplished by manipulating the ESRP priority setting for each VLAN for the particular ESRP switch.

Configuration commands for the first ESRP switch are as follows:

create vlan sales
configure vlan sales tag 10
configure vlan sales add ports 1:1-1:2
configure vlan sales add ports 1:3, 1:5 tagged
configure vlan sales ipaddress 10.1.2.3/24
create vlan engineering
configure vlan engineering tag 20
configure vlan engineering add ports 1:4
configure vlan engineering add ports 1:3, 1:5 tagged
configure vlan engineering ipaddress 10.4.5.6/24
create esrp esrp1
configure esrp esrp1 domain-id 4096
configure esrp esrp1 add master sales
configure esrp esrp1 priority 5
enable esrp esrp1
create esrp esrp2
configure esrp esrp2 domain-id 4097
configure esrp esrp2 add master engineering
enable esrp esrp2

Configuration commands for the second ESRP switch are as follows:

create vlan sales
configure vlan sales tag 10
configure vlan sales add ports 1:1-1:3
configure vlan sales ipaddress 10.1.2.3/24
configure vlan sales add ports 1:5 tagged
create vlan engineering
configure vlan engineering tag 20
configure vlan engineering add ports 1:4, 2:1
configure vlan engineering ipaddress 10.4.5.6/24
configure vlan engineering add ports 1:5 tagged
create esrp esrp1
configure esrp esrp1 domain-id 4096
configure esrp 1 add master sales
enable esrp esrp1
create esrp esrp2
configure esrp esrp2 domain-id 4097
configure esrp esrp2 add master engineering
configure esrp esrp2 priority 5
enable esrp esrp2