Configuring a Layer 3 dynamic aggregation group

Prerequisites

You must be in the global configuration context: switch(config)#

Procedure

Create a Layer 3 aggregate interface and access the Layer 3 aggregate interface view by entering:
```
switch(config)# interface lag <ID>
```
The range of the LAG interface ID is 1 to 256.

While creating the Layer 3 aggregate interface, the system automatically creates a Layer 3 dynamic aggregation group numbered the same.
Set the operational state of every interface in the LAG to up by entering:
```
switch(config-lag-if)# no shutdown
```
NOTE:
This command does not impact the administrative state of the member interfaces because the command was entered at the level of the LAG. To change the administrative state of a member interface, enter the command at the interface level. For example:
```
switch(config)# interface 1/1/2
switch(config-if)# no shutdown
```

Configure the aggregation group to operate in dynamic mode by entering:

switch(config-lag-if)# lacp mode {active | passive}

For example:

switch(config-lag-if)# lacp mode active

Set the IP address on the LAG interface by entering:

switch(config-lag-if)# ip address <IPV4-ADDR>/<MASK>

For example:

switch(config-lag-if)# ip address 192.0.2.1/30

Use the following steps to add a maximum of eight interfaces to the LAG:
1. Assign an interface to the LAG:
```
switch(config-lag-if)# interface <PORT-ID>
```
  For example:
```
switch(config-lag-if)# interface 1/1/1
```
  See the Command-Line Interface Guide for your switch and software version for more information about the interface <PORT-ID> command.
2. Assign an ID to the LAG:
```
switch(config-if)# lag <ID>
```
  For example:
```
switch(config-if)# lag 100
```
3. Set the administrative state of the member interface to up:
```
switch(config-if)# no shutdown
```

Adding two interfaces to a Layer 3 dynamic LAG

switch(config)# interface lag 100
switch(config-lag-if)# no shutdown
switch(config-lag-if)# lacp mode active
switch(config-lag-if)# ip address 192.0.2.1/30
switch(config-lag-if)# interface 1/1/1
switch(config-if)# lag 100
switch(config-if)# no shutdown
switch(config-if)# interface 1/1/2
switch(config-if)# lag 100
switch(config-if)# no shutdown
switch(config-if)# show running-config
...
!
vlan 1
interface lag 100
    no shutdown
    ip address 192.0.2.1/30
    lacp mode active
interface 1/1/1
    no shutdown
    lag 100
interface 1/1/2
    no shutdown
    lag 100
switch(config-if)#