16. Configuring EIGRP Hello Hold Timers

hello and welcome to this tutorial on how to configure the EIGRP hello and hold time or values now just like it was in OSPF these are optional configurations so you don't have to do this but perhaps you might want to in order to optimize your network a little bit so just a refresher the hello timer dictates how often hello messages are sent and the default value depends on the speed of that link but usually it defaults to five five seconds the whole timer states how long a router is going to wait to receive a hello message from a neighbor before declaring it down so it has to receive at least one hello message within that time otherwise it thinks the neighbors down this value defaults to 15 usually but again it depends on the type of network you're on it is a best practice to configure this timer to be three times the value of the hello timer so if we go ahead and configure our hello timer to be two then we want our whole timer to be six our lab is going to be the same as the previous EW GRP and OSPF tutorials we already have a I gr P configured we're going to go ahead and change the timer values on router a we will make the hello timer two seconds and the whole timer six seconds so let's begin by determining the current values to figure out the hello timer it's pretty simple show IP e IG RP interface detail and it's really obvious hello interval is five seconds now that's the default value for this particular interface now determining the whole timer is a little bit trickier you can issue the show IP e IG RP neighbour command and the forth column all over it says hold seconds well that's the elapsed time since this router last heard a hello message from this neighbor which is router B so we can keep issuing his command and you'll see it resets every time it gets a hello message so you can try to infer from this this information but that's a little bit tricky it's not exact it's not exactly exact so for that reason you really have to just memorize that by default the whole timer is going to be 3 times the hello timer and that like we mentioned earlier is the best practice that's what cisco recommends you configure now that's if you're using default values if you're not using default values then you can actually go ahead and check your configuration since both of these are interface sub commands we can check out the running configuration on serial zero zero zero and if you don't see anything there then you have to assume you're running with the default timer values okay so let's go ahead and make some changes we go into serial zero zero zero and to change the hello timer the command is IP hello interval EW GRP and then we have to state our AAS number which is 21 and then the time so we're going to use two seconds now to set the whole timer it's IP hold time eeew GRP again the AES number and then the number of seconds so we'll set this for three times two which is six and that's it if we want to go ahead and do the quick verification you can check out the interface running configuration or if you want you can go ahead and check out the interfaces detail command for show IP e IG R P and now you can see hello interval is two seconds okay okay so let's summarize what we covered in terms of configuration commands we can issue the IP hello interval EW GRP command in order to change the hello interval or we can issue the IP hold time EW GRP command to adjust the whole time don't forget in each one of those commands you have to issue the AES number we talked a little bit about the default values and remember the default value for the whole timer is going to be three times that of the hallo timer to verify our work we can go ahead and check out the show I Pei GRP interface detail command to learn the hello interval we can check out the running configuration to see if we're using values that are different than the defaults and to get a rough idea of the whole timer we can issue the show IP EIGRP neighbour command and that tells you how much time has passed since we last received a hello from the neighbor okay so that's it that is how you configure the EIGRP hello and hold timer values thanks for watching

Channel: System Engineer

Views: 1,419

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Id: mWOUNm4hU8c

Length: 5min 20sec (320 seconds)

Published: Tue Apr 25 2017