Good morning

How do i go about setting up a loopback interface in the board for use of the OSPF

Just create a bridge interface with zero member ports. The interface will always be active and thus will function as a regular loopback interface. This is the only way to emulate a loopback using RouterOS.

Good morning

How do i go about setting up a loopback interface in the board for use of the OSPF

Why do you need OSPF loopback and what MT OS version are you running on the board.

Just create a bridge interface with zero member ports. The interface will always be active and thus will function as a regular loopback interface. This is the only way to emulate a loopback using RouterOS.

Code: Select all

/interface bridge add name=loopback0

thanks. i'll try that

Good morning

How do i go about setting up a loopback interface in the board for use of the OSPF

Why do you need OSPF loopback and what MT OS version are you running on the board.

in a cisco router when you setup ospf you put the RID on o loopback int, other wise when the int goes down so does the ospf.

well i have spotted the same issue within Mtik. i did think i'd have the same issue as i could not find anyway to make a loopback device but it seems the issue is also present in Mtil. this is why i'm looking for an int that will only go down when the router goes down

Yes, the same issue is indeed present in RouterOS, and the method with the bridge is the way to solve it.

anyways, thanks [all] for all the help
i'll drive into this slowly to make sure i don't break a system that at least appears to be working

Yes, the same issue is indeed present in RouterOS, and the method with the bridge is the way to solve it.

Does this still apply to MT OS 5.X series as well?

OSPF router ID should not be changed after the OSPF process has been started. OSPF router ID change resets all OSPF adjacencies, resulting in temporary router outage. The router also has to originate new copies of all its LSAs with the new router ID. Stale copies of the LSAs originated by the “old” OSPF process remain in the OSPF topology databases of all routers until they expire (their age increases beyond max-age).

Quoted from http://wiki.nil.com/OSPF_Router_ID_selection_algorithm

This document has a small mention of the router-id parameter, and instructions on creating a loopback interface and assigning an IP to it.
http://wiki.mikrotik.com/wiki/Manual:OSPF-examples

Yes, the same issue is indeed present in RouterOS, and the method with the bridge is the way to solve it.

Does this still apply to MT OS 5.X series as well?

While I cannot answer for the specific OSPF implementation of RouterOS, best practice networking dictates that every device should have an ip-address that is not bound to a physical interface. In most OSPF implementations, the moment the OSPF service is started it binds to an interface, thus if you do not have a non-physical ip interface for it to bind to, any physical link event, e.g. loss of link, will impact the OSPF service.