notes: RIP Metrics & Timers

- RIP uses hop-count as a metric.
- 1 hop per interface.
- 16 hops = unreachable

Timers:

1. Update timer (30sec) - A router sends a response message out every RIP-enabled interfaces every 30 seconds on average.

2. Invalid timer (180sec)- Amount of time a route can stay in the routing table without being updated.

3. Holddown (180sec) - An update with a hop count higher that the metric recorded in the table will place a route in holddown.
- cisco proprietary. if you you are connecting a non cisco devices set holdtime to 0.

4. Flush timer (240sec) - The time when a invalid route get removed from the routing table.

- Before the flush timer expires, the invalid route will be advertised with the unreachable metric.
- Shows in the routing table as "x.x.x.x is possibly down"
- Timers must be changed in all RIP domain

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COMMANDS
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1. to change the timers under rip routing process.

timers basic {update} {invalid} {holddown} {flush}