Why does network warrior state this about equal cost

CodeBloxCodeBlox Member Posts: 1,363 ■■■■□□□□□□
in CCNA & CCENT
When a newer update is received for a route that hasalready been inserted into the routing table, the newer update is considered to bemore reliable, andis itself insertedinto the routing table, overwriting the previousentry. This means that each time Router B receives an update from Router A orRouter C, it will change its routing table to show that network 10.0.0.0 is behind the router from which it received the update.

He's referring to classful routing with RIP. His example is using a discontiguous network and the router in the middle(B) recieves advertisements from A and C for route 10.0.0.0/8. He basically makes it sound like router B will remove one of the routes, replacing it with the other when the timed update is sent, swapping the routes out. I do not think this is true, RIP will load balance the equal cost paths, not replace one of them with the other.

He also says that RIPv2 has a max hop count of 255. I'm pretty sure it's got the same limitation of 16 just as RIPv1. I'm not at home in the lab to test this right now so...
Currently reading: Network Warrior, Unix Network Programming by Richard Stevens
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  • tr1xtr1x Member Posts: 213
    Max hop count is 255 for RIPv2. I don't think RIP load balances by default, isn't that something you have to enable with maximum-paths command?
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  • veritas_libertasveritas_libertas Member Posts: 5,746 ■■■■■■■■■■
    tr1x wrote: »
    Max hop count is 255 for RIPv2. I don't think RIP load balances by default, isn't that something you have to enable with maximum-paths command?

    It load balances by default. This can be a good and bad thing. Bad because it doesn't make a distinction between a fast and slow link.
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  • tr1xtr1x Member Posts: 213
    Thanks for the info.. how come it's not load balancing in CodeBlox's example?
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  • CodeBloxCodeBlox Member Posts: 1,363 ■■■■□□□□□□
    tr1x wrote: »
    Max hop count is 255 for RIPv2. I don't think RIP load balances by default, isn't that something you have to enable with maximum-paths command?

    It does load balance by default. I'll check the hop count thing when I get home... Could have sworn it was 15 just as in RIPv1
    Currently reading: Network Warrior, Unix Network Programming by Richard Stevens
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  • tr1xtr1x Member Posts: 213
    You're absolutely right, I'm sorry. I must have been thinking of another routing protocol. I just looked it up on a few different web pages, max hop count is 15. I also found a post on another forum very similar to yours, I'd say the author of Network Warrior is wrong. Thanks for finding it, I'll be reading that book in a couple months.
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  • MickQMickQ Member Posts: 628 ■■■■□□□□□□
    The maximum paths command is for EIGRP, as that's the only protocol that can do unequal load balancing (AD&FD). The others, which do load balancing, will do it over equal metric cost links.
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  • ZartanasaurusZartanasaurus Member Posts: 2,008 ■■■■■■■■■□
    tr1x wrote: »
    You're absolutely right, I'm sorry. I must have been thinking of another routing protocol. I just looked it up on a few different web pages, max hop count is 15. I also found a post on another forum very similar to yours, I'd say the author of Network Warrior is wrong. Thanks for finding it, I'll be reading that book in a couple months.
    Yes, it's EIGRP with a max hop count of 255.
    Currently reading:
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  • ZartanasaurusZartanasaurus Member Posts: 2,008 ■■■■■■■■■□
    MickQ wrote: »
    The maximum paths command is for EIGRP, as that's the only protocol that can do unequal load balancing (AD&FD). The others, which do load balancing, will do it over equal metric cost links.
    Maximum-paths can be used with RIP. It's for equal cost load-balancing. To do unequal-cost load balancing for EIGRP, you use the variance command.
    Currently reading:
    IPSec VPN Design 44%
    Mastering VMWare vSphere 5​ 42.8%
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  • MickQMickQ Member Posts: 628 ■■■■□□□□□□
    Thanks :)
    Good to know for future use, just in case.
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  • ElvisGElvisG Member Posts: 167
    Speaking of this, I just finished reading "31 days before your CCNA exam" and it said RIPv1 was 15 and RIPv2 was 25. I had just finished The Network Warrior and just assumed that the author meant 25 instead of 255. It's funny though because everyone says it's 15. I am gonna assume that the answer is 15 but it's weird that two books have it written like that.
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  • MickQMickQ Member Posts: 628 ■■■■□□□□□□
    ElvisG wrote: »
    Speaking of this, I just finished reading "31 days before your CCNA exam" and it said RIPv1 was 15 and RIPv2 was 25. I had just finished The Network Warrior and just assumed that the author meant 25 instead of 255. It's funny though because everyone says it's 15. I am gonna assume that the answer is 15 but it's weird that two books have it written like that.

    Whenever I see something like that, so so similar to a power of two (2^4), I always consider that it might be a typo.
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