Qualified to Hop

Floating static routes are known as something different in the world of Juniper. Qualified Next Hops. It allows an independent routing preference on a route where there is two routes to the same destination. This blog here will show you how to configure this route. Below is the topology I am using.

SRX110 with qualified routes

The idea on this setup is if a direct peered upstream router drops you have a deterministic failover situation. Here I assume interfaces have been setup and we are just focusing on the static routing.

set routing-options static route 0.0.0.0/0 next-hop 172.84.23.1
set routing-options static route 0.0.0.0/0 qualified-next-hop 172.84.23.2 preference 6

A static route has a defined routing preference of 5 by default; as set by Juniper. The backup or floating route I have defined is set at 6. Lower is better in the case of routing. When the route being used is withdrawn from the routing table the qualified next-hop comes into play. Now just a show command under routing-options to see the config.

[edit routing-options]
[email protected]# show
       static {
             route 0.0.0.0/0 {
                     next-hop 172.84.23.1;
                     qualified-next-hop 172.84.23.2  {
                     preference 6;
                   }
             }
    }

Now to look at the routing table.

[email protected]> show route protocol static

inet.0: 2 destinations, 3 routes (2 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

0.0.0.0/0          *[Static/5] 00:02:12
                    > to 172.83.23.1 via fe-0/0/0.0
                    [Static/6] 00:02:12
                    > to 172.83.23.2 via fe-0/0/1.0

Here I am simulating a failover of the upstream link.

[email protected]# deactivate interfaces fe-0/0/0 unit 0 family inet address 172.83.23.1/24
[email protected]# commit

Now to check the routing table to see if failover occurred.

[email protected]> show route protocol static

inet.0: 2 destinations, 2 routes (2 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

0.0.0.0/0           *[Static/6] 00:02:24
                    > to 172.83.23.2 via fe-0/0/0.0

There you go. As expected the function of the qualified next-hop on JUNOS. Add that to your IOS to JUNOS transition skill set.

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