RIP Timers Debug

This topic is to discuss the following lesson:

Hi Rene,

I’ve been waiting for your debugging, Thank you very much about this, that’s was very Interesting to me.
Can you also do debugging about Flash Update Threshhold timer and Sleep Timer, please?

If I have some spare time I’ll see if I can debug these two.

The flash update threshold timer is apparently used to suppress the flash update (triggered update) when it’s X seconds within the scheduled routing update (which is sent every 30 seconds).

The sleeptime is a funny one…it sets the delay in milliseconds how long we wait to send the scheduled routing update when a flash update is sent. I looked around for this and even though the RIP command supports it, it doesn’t seem to work.


Brilliant as always, the Cisco docs are just confusing, thanks for this clarification.

that’s a very detailed explanation. Thanks buddy, you are genius :slight_smile:


Awesome article. I have a question though: what happens if you change the timer for a router and not for others? While it’s better to have same timers; still, since no adjacency is needed to form, is it recommended if you change timer on one device only? I had seen such case where you have linux (unmanaged) router on one end and CISCO router at other and update timer being shortened in CISCO router only. Not sure about the consequences, then. Any thoughts?


By unmanaged, I meant Linux router running RIP v2 but timers not changeable, at least on operational level.

Hi Deep,

RIP doesn’t form a neighbor adjacency so you could change the timers on one end only if you want. The only thing I can think of why you want to do this is if you want your linux router to learn routes ASAP. In that case, you could reduce the timers on your Cisco router only.

To keep things simple, it’s probably best to use the same timers everywhere :slight_smile:


Hello Rene,
It’s brilliant explanation. There is one thing i dont uderstand.

When holdown timer activates R2 starts sending poison routes messages.
And R3 as you said immediately remove the route from the routing table. Also as you said R3 send back to R2 poison route message.

The question is ---- why does R2 not remove the route from routing table in spite R2 get poison route message from R3 ?

Hi Aleksandr,

This probably happens because R2 has learned the route through R1. It receives the poison reverse from R3 but that’s not where we learned the route from…

it wouldn’t make sense if we used this information to remove the route from the routing table