Please consider the following from my book:
The last option you may use with the commit command is synchronize. When you have arouter with two Routing Engines installed, you can have the router apply the candidate configurationto both Routing Engines.user@router# commit synchronizere0: configuration check succeedsre1: configuration check succeedsre0: commit completere1: commit completeuser@Shiraz#This option is helpful in the event of a Routing Engine failure; the backup Routing Enginenow has the latest operational parameters in the network.
Let say we have a Juniper router with two RE; RE1, RE2
RE1 is active . we configure OSPF on RE1, we commit the change without " synchronize". After a few days, RE1 crashes,
Will the new RE2 have OSPF config ? If yes, why we have not used "commit synchronize"
To put it another way:
Does using " only commit" not allow RE2 to get synch with RE1's config?
Do we have to use " commit synch " to force R2 synch with RE1's config?
Thanks and much apprecaited!!
No. Commit will not replicate the changes to the backup RE.
Please mark my solution as accepted if it helped.
It is also possible to embed "commit synchronize" in system settings so that just issuing a commit will automatically synchorize the config accross REs. Recommended for dual-REs.