Add a backup default route that only kicks in on failure
A site has a primary uplink and an idle backup. Add a floating static default route so the backup is used only when the primary's route is gone.
Scenario
r1 has two uplinks: a primary via 10.0.12.2 and a backup via 10.0.13.2. Today only the primary
default route is configured. You want a floating static backup: a second default route that the
router ignores while the primary is up, and falls back to when the primary's route disappears.
A static route's preference is its administrative distance (default 1). Give the backup a higher distance so it stays out of the table until the primary is gone.
Your job
In r1/frr.conf, add a second default route via 10.0.13.2 and give it an administrative distance
higher than the primary's, so it stays out of the table until the primary's route disappears.
What "done" looks like
Two default routes: the primary via 10.0.12.2 at the default distance, and a floating backup via
10.0.13.2 at a higher distance.
Teaches: administrative distance and floating static routes. A higher-distance backup route waits in reserve and only installs when the preferred route fails.
What gets checked
Your solution is verified against each of these:
- A primary default route via the main uplink exists
- A backup default route via the secondary uplink exists
- The backup has a higher administrative distance, so it's only used on failover
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