[HECnet] One more for the Cisco GRE mesh: Seeking Tunnel End-Points

[Johnny Billquist]

Supratim, you are stumbling into a slight issue when doing this.

DECnet routing is kindof stupid. When a node in one area wants to talk 
to a node in another area, the only thing it does is figure out how to 
get to that area. And that just means find the lowest cost path to any 
node in that area. And here it where it gets silly.

Until a couple of days ago, CTAKAH:: had the same cost for all circuits. 
That resulted in CTAKAH choosing IMPVAX for all communication to area 1. 
So even though CTAKAH and MIM have a direct circuit between them, 
packets from CTAKAH (in Russia) and MIM (in Sweden) were travelling over 
New York.

CTAKAH have now dropped the cost for the circuits to MIM to a little 
lower, meaning it will prefer this link. But that also means that even 
through CTAKAH and IMPVAX have a direct connection, all packets from 
CTAKAH to IMPVAX will pass over MIM.

In essence, this is how DECnet works, and you cannot get around this. 
When multiple connections to a different area exists, it is going to be 
suboptimal. The one thing would could do to improve things a bit would 
be to move you to an area of your own. Then both links would become 
useful for more than redundancy backup.

   Johnny

On 2019-02-26 20:53, Supratim Sanyal wrote:
> This email is directed to owners of Cisco routers with GRE tunnels; to 
> the best of my limited knowledge, Dave McGuire, Ian McLaughlin, Brian 
> Hechinger, Mark Darvill, Cory Smelosky, Peter Löthberg ... who else?
> 
> I already have a stable GRE tunnel to A12RTR for a while now, and am 
> looking for end-points on other Cisco routers on HECnet to connect to. I 
> will be coming in from IP address 45.62.248.66, DECnet node 1.919.
> 
> If possible, please let me know what GRE end-points I can connect to. 
> You can, of course, DM me too.
> 
> Thank you.
> 
> Supratim
> +1-240-483-8572 (cell)
> 
> 
> 
> 
> 
> 
> 
> 


-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol