Setting the Hop Limit for Dynamic Bypass CSPF

The user can configure an interface level hop-limit for dynamic bypass LSPs corresponding to a protected link.

The user can compute a dynamic bypass path, so the hop-limit is the minimum of the backup requested hop limit and the interface mode configured hop limit. This computed hop limit is set as the dynamic bypass LSP hop limit during the initial creation of the dynamic bypass.

At the time of re-optimization, the dynamic bypass hop limit is modified so it is at its minimal ((hop limits of all riding backup paths), interface configuration hop-limit).

To set the hop limit for dynamic bypass CSPF, complete the following steps.

Enable the device for configuration.
```
device>configure
```
Enable the MPLS router.
```
device(config)# router mpls
```
Enable MPLS-capable interfaces and specify the selected interface. In this example, the selected Ethernet interface is 0/8.
```
device(config-router-mpls)# mpls-interface ethernet 0/8
```

Enable the interface level dynamic bypass.

device(config-router-mpls-if-ethernet-0/8)# dynamic-bypass

Configure the hop limit. In this example, the hop limit is configured to four (4).
```
device(config-router-mpls-if-ethernet-0/8-dynamic-bypass)# hop-limit 4 
```

Example

The following example combines the steps above to set the hop limit for dynamic bypass CSPF to four (4).

device>configure
device(config)# router mpls
device(config-router-mpls)# mpls-interface ethernet 0/8
device(config-router-mpls-if-ethernet-0/8)# dynamic-bypass
device(config-router-mpls-if-ethernet-0/8-dynamic-bypass)# hop-limit 4