Create all NNI's as an MLT?

[Anonymous]

Hi,

Very simple question, just testing the idea of putting every single link NNI into an MLT. My theory is that with ISIS being a P2P protocol, it might be good practise to do this as it would be easy to add another link if required.

That seem like a logical idea?

Just testing the water in case there is some component that I am missing.

Only downside I see is that you are adding another protocol layer to a single link that doesn’t necessarily need it, but is generally very stable.

When I label the MLT’s I am using the port number i.e. slot 1 port 45 is MLT145, slot 3 port 12 is MLT 312, if using LACP I am also using that number as the key. If IST I am using 501.

If more then one port is on same switch in an MLT I use the first port.

Obviously doesn’t work for an 8600 has MLT numbering is 1-512, but generally works. Makes it very quick and easy to see what ports belong to an MLT without searching for it, and has a general rule to follow that works.

Anyway, see what anyone else might do?

Many thanks in advance

[Anonymous]

Hi Paul,

Thanks for posting back.

Just to clarify, I’m not clear on why the MLT’s would show an error state. In terms of creating the group and enable it as an NNI, is this the type of configuration you would expect to see:

mlt 501 enable name "MLT to xxxx"
mlt 501 member 1/18
mlt 501 encapsulation dot1q

interface mlt 501
isis
isis spbm 1
isis enable
exit

Many thanks

[EXTR_Paul]

This will work.   The only issue is that you will have all your MLTs in an error state, all the time.

When I build fabrics with customers, when its a single NNI its a point-to-point NNI.   If its an MLT/NNI then we create the group and enabled it as an NNI.