Default ospf hello time 10 s, 40 s dead time, if there is comparison between two adjacent routers complex network, if the middle network failures, and corresponding port router did not down, so only more than dead time can detect inaccessible, will recount the routing table, that is to say at least 40 s time such as network can restore... Customers hope as soon as possible, then adjust the hello 1 s, 4 s dead, so is it a lot... But don't know what is the effect of this setting, I can think hello small time interval, the multicast handshake packet will increase, to some extent, increased the bandwidth, but if enough bandwidth, and other aspects have what effect? For the great god your advice!

CodePudding user response:

For different types of networks, Hello timer and neighbors expiry time is different, the default value of modified network type, Hello timer and neighbors expiry time will restore to the default value of network type, please make sure that the Hello at the ends of the neighbor router failure time is consistent with the value of the timer and neighbours, otherwise will affect the OSPF neighbor relationship established,
When OSPF LSDB change, need to calculate the shortest path, if the network change frequently, and each change immediately calculate the shortest path, it will take up a lot of system resources, and affect the efficiency of the router,

CodePudding user response:

reference 1st floor qq_34490011 response:

for different types of networks, Hello timer and neighbors expiry time is different, the default value of modified network type, Hello timer and neighbors expiry time will restore to the default value of network type, please make sure that the Hello at the ends of the neighbor router failure time is consistent with the value of the timer and neighbours, otherwise will affect the OSPF neighbor relationship established,
When OSPF LSDB change, need to calculate the shortest path, if the network change frequently, and each change immediately calculate the shortest path, will take up a lot of system resources, and affect the efficiency of the router,

thank you very much, the customer is broadcast network, demand recovery time is fast, the default 40 s, they can't accept, adjust the hello 1 s dead 4 s, it looks good, but I don't know what other aspects affect the

CodePudding user response:

Network on both ends of the Hello Time and Deadth Time inconsistency will cause the failure of OSPF neighbor build, of course can be change, but will also face some problems, if you have your topology is not stable, so the routing convergence, and can't generally small local area network (LAN) this question is not obvious, so completely can according to your idea to design these parameters, if your network is large enough, I want to also won't, because this is OSPF, ha, ha, ha, generally OSPF routing loss as long as it doesn't lead to oscillation, so you can follow one's inclinations,
This value is the manufacturer's advice, general is according to certain Base line, give you change is on-demand configuration, so the change or not is that you are going to learn or use it, it all depends on you have the ability to control risk, of course, if you are a good web designers, this is not a problem, can at the time of planning can provide an area can think how to play how to play,
I hope it can help you,

CodePudding user response:

You check a technology, BFD, do an ospf and BFD linkage, can realize millisecond level switch, also need not modify the ospf interval