[j-nsp] ospf rid lo0 stub advertisement

[Aaron]

I am using logical systems in my lab and trying to see the
auto-advertisement of the lo0 interface working and it's not.  Any ideas ?

 

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https://www.juniper.net/assets/us/en/local/pdf/study-guide/study-guide-jncip
.pdf

 

page 178 of 708 (page is actually labeled page 156) mentions the following.

 

By default JUNOS software will obtain the OSPF router ID from the first
interface that is detected with a non-Martian address. Because lo0 is always
the first interface examined when rpd starts, explicit configuration of the
RID under routing-options is rarely necessary. Simply assigning the desired
IP address to the lo0 interface results in a stable and deterministic router
ID.  

 

JUNOS software automatically advertises a stub route to the interface from
which the RID is obtained; therefore it is not actually necessary to
explicitly configure lo0 as an OSPF interface to meet the lo0 connectivity
requirements of this configuration example.

 

Manually configuring the RID under routing-options will affect connectivity
to the lo0 address, as the router will no longer include a stub route for
its lo0 interface. You will have to enable OSPF on the lo0 interface, as
done in the previous example, if lo0 connectivity is required and you have
assigned the RID manually.

 

Omitting the lo0 interface from your OSPF configuration results in the lo0
address being advertised as a stub network in the router LSAs (type 1 LSAs)
that are generated and flooded into all areas to which a given router
attaches.

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-Aaron