Configuring IPsec on an OSPFv3 interface

For IPsec to work, the IPsec configuration must be the same on all the routers to which an interface connects.

Note

Ensure that OSPFv3 areas are assigned. All device interfaces must be assigned to one of the defined areas on an OSPFv3 router. When an interface is assigned to an area, all corresponding subnets on that interface are automatically included in the assignment.

Enter the configure terminal command to access global configuration mode.
```
device# configure terminal
```
Enter the interface command and specify an interface.
```
device(config)# interface ethernet 1/1
```
Enter the ipv6 ospf area command to assign a specified area to the interface.
```
device(conf-if-eth-1/1)# ipv6 ospf area 0
```
Enter ipv6 ospf authentication spi value esp null hmac-sha1 and specify a 40-character hexadecimal key.
```
device(conf-if-eth-1/1)# ipv6 ospf authentication spi 512 esp null hmac-sha1 key abcef12345678901234fedcba098765432109876
```
IPsec is configured on the specified interface with a security parameter index (SPI) value of 512, and the Encapsulating Security Payload (ESP) protocol is selected. Secure Hash Algorithm 1 (SHA-1) authentication is enabled.

The following example enables ESP and SHA-1 on a specified OSPFv3 Ethernet interface.

device# configure terminal
device(config)# interface ethernet 1/1
device(conf-if-eth-1/1)# ipv6 ospf area 0
device(conf-if-eth-1/1)# ipv6 ospf authentication spi 512 esp null hmac-sha1 key abcef12345678901234fedcba098765432109876