Please help me on below two queries.
-
In ospf , what is difference between
under the router ospf
redistribute connected and redistribute connected subnets ? -
In which scenario/use case E1 metric will be used. Is there any lesson/lab on this.
Hello Manish
Without the subnets keyword, only routes that are in the routing table with the default classful mask will be redistributed. When you use the subnets keyword, the subnets from the connected interfaces are redistributed with their appropriate prefixes. A detailed explanation can be found at this Cisco documentation:
The following lab may be of help for this question:
You may also find this post useful:
If you have any further questions, please let us know!
I hope this has been helpful!
Laz
1 Like
Thank you very Laz. One more doubt on OSPF, How routing loop is handled in ospf. Basically what scenario a loop can happen in ospf.
Hello Manish
OSPF, as a link-state protocol, enables each router to have a complete map of the network. This helps in preventing most routing loops. Secondly, as OSPF networks get larger, they are separated into distinct areas. These areas are all obligated to connect to area 0, thus creating a loop-free inter-area topology where traffic from one area to another must go through area 0.
This whole design of OSPF helps to alleviate the possibility of having routing loops. There is no “loop avoidance” technique employed by OSPF since loop avoidance is built into the shortest path first (SPF) algorithm.
Routing loops may be introduced into OSPF whenever you interconnect with other routing domains running different routing protocols, especially if you have two or more connections to these other domains. In such a case, you can use route tagging to avoid loops. This is further described in the following lesson:
I hope this has been helpful!
Laz
1 Like
Thank you Laz. Appreciate your response.
1 Like