A differences of redistrubuted command on CLI for OSPF and EIGRP

[bearerman]

Hi everyone, i would like to ask about what's a differences of redistribute command on cisco CLI for OSPF, EIGRP and RIP route? need help to get through it, thank you

[M02@rt37 · Accepted solution]

Hello @bearerman,

The redistribute command in CLI is used to redistribute routes from one routing protocol into another. 

--OSPF
To redistribute routes into OSPF, you typically use the redistribute command under the OSPF routing process, such as "router ospf [process-id]."
You specify the source routing protocol using a subcommand, like "redistribute connected" or "redistribute static." This command is entered in OSPF configuration mode. You also need to specify a metric for redistributed routes using the "metric" subcommand.

--EIGRP
To redistribute routes into EIGRP, you configure the redistribution under the EIGRP routing process with the "redistribute" command.
Specify the source routing protocol, such as "redistribute OSPF" or "redistribute RIP," along with a metric using the "metric" subcommand. EIGRP typically uses the "redistribute" command within the EIGRP configuration section.

--RIP
To redistribute routes into RIP, you also use the "redistribute" command within the RIP routing process, which is usually under "router rip" configuration.
Specify the source routing protocol, like "redistribute OSPF" or "redistribute EIGRP," along with a metric using the "metric" subcommand. Be aware that RIP uses hop count as its metric, so other metrics might need to be converted to hop count when redistributing into RIP.

The redistribute command is used in a similar way for these routing protocols, but it's specific to the routing protocol configuration section and includes details about the source routing protocol and metrics.

[bearerman]

thank you for your response M02@rt37 

[M02@rt37]

You're so welcome @bearerman 

[Richard Burts]

I am not clear what you are really trying to ask. There are many similarities in redistribution in these protocols, redistribution injects routing information from a source protocol into the protocol you are configuring, so you specify the source, you may specify details about the metric to use, and you may specify some filtering for routes to redistribute. But your question seems to be about differences in the protocols. There are differences in the protocols in how you specify the metric. In many versions of IOS there is a difference in redistribution in OSPF that you may need to use the parameter "subnets" (but some versions of IOS do not need this).

If you still have questions about redistribution please clarify what the questions are.

[bearerman]

thank you for your response @Richard Burts , it is already been solved actually but let me get this straight first, the question actually was about on what condition that i have to use a "metric" or a "subnets" command after i wrote redistribution command in OSPF, EIGRP and RIP Route, but like i said before its already been solved, thank you once again for your concern and see you in next conversation

[Joseph W. Doherty]

Usually there are different options, per protocol, because each routing protocol has its own "view" of how a network topology should be "sliced and diced" and you're trying to provide the destination information a particular routing protocol uses.

[Giuseppe Larosa · Accepted solution]

Hello @bearerman ,

I would suggest you to take it from the opposite way:

what is needed to redistribute a different routing protocol or process into an EIGRP process, OSPF process or router RIP ?

you need to specify a seed metric , that is the metric to be used by the injected routes when entering the new routing domain.

This is the most important  concept to grab.

The seed metric depends on the nature of the protocol that will receive the routes:

for RIP is an hop count and taking in account that 15 is infinite for RIP you should use a low value like 3-5

for OSPF is an integer value . OSPF has two types of external routes O E2 and O E1 with O E1 preferred over O E2 and with O E2 the default type . O E1 are recommended if you have multiple ASBR nodes = multiple devices that inject routes into the same OSPF domain . with O E1 the seed metric is counted with the internal metric to the ASBR and this allows for better routing decisions.

OSPF may require the subnets keyword to avoid automatic route summarization during the redistribution . This was mandatory in the past.

For EIGRP that has a composite metric you need to provide the values for delay bandwidth reliability load and MTU to have  a successful redistribution from another dynamic protocol  ( unless  are connected or static routes ).

The set of values for EIGRP can be provided with the command default-metric at EIGRP process level or it can be provided in the redistribute command.

Be also aware that redistribution is a dynamic process it does not happen only once it is always on .

In order to be redistributed the routes from the source protocol have to be installed in the local node IP routing table ( unless they represent connected routes)

Hope to help

Giuseppe

[bearerman]

thank you for your response @Giuseppe Larosa