anyone else seeing very long AS paths?

Hank Nussbacher hank at efes.iucc.ac.il
Tue Feb 17 00:07:36 CST 2009


On Mon, 16 Feb 2009, Jon Lewis wrote:

> Is there a reason you don't use something like "bgp maxas-limit NN" on your 
> transit sessions?

I've been using maxas=50 for years now (see the 2005 thread:
http://www.atm.tut.fi/list-archive/nanog-2005/msg04753.html)
I also knew this would happen one day and have tried to get various lists 
"engaged" but the consensus was "live with it".

Here is just my 3 month logs:

Nov 30 18:51:32: %BGP-6-ASPATH: Long AS path 8551 3491 7473 45147 18351 
24532 24532 24532 24532 24532 24532 24532 24532 24532 24532 24532 24532 
24532 24532 24532 24532 24532 24532 24532 24532 24532 24532 2
Dec 17 20:47:33: %BGP-6-ASPATH: Long AS path 8551 174 5391 43179 43179 
43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 
43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 
43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 
43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 
43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 43179 
43179 43179 43179 43179 43179 43179 43179 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Dec 24 01:52:20: %BGP-6-ASPATH: Long AS path 8551 174 34224 42555 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Dec 24 02:02:27: %BGP-6-ASPATH: Long AS path 8551 174 34224 42555 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Dec 27 12:31:57: %BGP-6-ASPATH: Long AS path 8551 174 34224 42555 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Dec 27 12:33:16: %BGP-6-ASPATH: Long AS path 8551 3491 174 34224 42555 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Dec 27 12:46:49: %BGP-6-ASPATH: Long AS path 8551 174 34224 42555 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 48262 
48262 48262 48262 48262 48262 48262 48262 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Jan  7 19:26:45: %BGP-6-ASPATH: Long AS path 8551 12989 19181 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 received from 128.139.247.2: More than configured 
MAXAS-LIMIT
Jan  7 19:30:27: %BGP-6-ASPATH: Long AS path 8551 12989 19181 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 received from 128.139.247.2: More than configured 
MAXAS-LIMIT
Jan  7 19:38:06: %BGP-6-ASPATH: Long AS path 8551 12989 19181 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 6488 
6488 6488 6488 6488 6488 received from 128.139.247.2: More than configured 
MAXAS-LIMIT
Jan 10 04:57:12: %BGP-6-ASPATH: Long AS path 8551 3257 6453 12968 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Jan 10 05:26:57: %BGP-6-ASPATH: Long AS path 8551 3257 3356 12968 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Jan 10 05:37:06: %BGP-6-ASPATH: Long AS path 8551 3257 1299 1299 1299 1299 
8246 39412 39412 39412 12741 12968 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 received from 128.139.247.2: More than 
configured MAXAS-LIMIT
Jan 10 05:37:52: %BGP-6-ASPATH: Long AS path 8551 3491 3549 3320 3320 8246 
39412 39412 39412 12741 12887 3257 3356 12968 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 received from 128.139.247.2: More than 
configured MAXAS-LIMIT
Jan 20 10:57:05: %BGP-6-ASPATH: Long AS path 8551 3356 12968 33838 33838 
33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 
33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 
33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 33838 
33838 33838 33838 received from 128.139.247.2: More than configured 
MAXAS-LIMIT
Feb 14 01:45:13: %BGP-6-ASPATH: Long AS path 8551 3257 3356 39412 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 received from 128.139.247.2: 
More than configured MAXAS-LIMIT
Feb 14 01:45:59: %BGP-6-ASPATH: Long AS path 8551 3257 12887 12741 39412 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
39625 39625 39625 39625 39625 39625 received from 128.139.247.2: More than 
configured MAXAS-LIMIT
Feb 16 18:23:45: %BGP-6-ASPATH: Long AS path 8551 3356 29113 47868 47868 
47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 
47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 
47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 
47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 
47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 
47868 47868 47868 47868 47868 47868 received from 128.139.247.2: More than 
configured MAXAS-LIMIT

A regular UN of attempts to do this previously:

24532 -  PT. Inet Global Indo, Indonesia
43179 -  Team Consulting AS, Bosnia and Herzegovina
48262 -  Noblecom Ltd., Bulgaria
6488 - Arizona Macintosh Users Group, USA
39625 - Omni-Araneo, Poland
33838 - BetaNET sp. z o.o, Poland
47868 - SUPRO, spol. s r.o., Czech Republic

"They" will keep trying and until a vast majority of ISPs implement maxas, 
this will keep happening.

-Hank

>
> We saw this too, but it stopped at our transit routers.  There was actually 
> another a few days ago.
>
> Feb 13 18:46:07: %BGP-6-ASPATH: Long AS path 4323 1299 12887 12741 39412 
> 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
> 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 39625 
> 39625 39625...
>
> Feb 16 11:24:53: %BGP-6-ASPATH: Long AS path 4323 3257 29113 47868 47868 
> 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 
> 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 
> 47868 47868...
>
>
> ----------------------------------------------------------------------
> Jon Lewis                   |  I route
> Senior Network Engineer     |  therefore you are
> Atlantic Net                |
> _________ http://www.lewis.org/~jlewis/pgp for PGP public key_________
>




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