IS-IS on FRR - Is Anyone Running It?

Saku Ytti saku at ytti.fi
Mon Apr 6 10:00:36 UTC 2020


Aah found it, it does do Cisco hack.

https://github.com/FRRouting/frr/blob/58980443821edf95719984e01f31720bd1dc7f79/isisd/isis_constants.h#L172-L180

But as long as you don't pad, your PDU shouldn't exceed 1500B.


On Mon, 6 Apr 2020 at 12:58, Saku Ytti <saku at ytti.fi> wrote:
>
> From your original post:
>
> > 2020/03/21 03:12:36 ISIS: isis_send_pdu_bcast: sock_buff size 8192 is less than output pdu size 9014 on circuit em0
> > 2020/03/21 03:12:36 ISIS: [EC 67108865] ISIS-Adj (1): Send L2 IIH on em0 failed
>
> Why is PDU 9014, if you don't have padding? I wonder what FRR even
> does at >1500B, I don't see '8870' in source code, so I don't think it
> supports the EthernetII hack.
>
> I wonder did someone verify the fix, to see what it even does? To me
> it looks like what it'll do, it'll use what ever ethernetII matches
> byte-size of frame, which is decidedly, not correct and would not
> interoperate after 'fix'.
>
> --
>   ++ytti



-- 
  ++ytti



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