[j-nsp] BFD timers for OSPF - MX80 - 10.3R2.11

[David Ball]

  Thanks, Doug (and the others, who replied earlier today).  Indeed
50ms appears too low on the MX80.  When I fail a link across which
LSPs (primaries or backups) pass, even those events being handled by
the RE can occasionally cause BFD to miss 3 hellos, shutting down the
OSPF neighbour.  I've tried at 100ms with better result, though your
recommendation of 150ms is well received.
  Do we know if this is something that *will* eventually be
distributed to the PFE in future releases on the MX80?

David


On 3 March 2011 15:27, Doug Hanks <dhanks at juniper.net> wrote:
> We generally recommend 150ms to most customers.  The added benefit of going from 150ms to 50ms is generally not enough to warrant the move.
>
> -----Original Message-----
> From: juniper-nsp-bounces at puck.nether.net [mailto:juniper-nsp-bounces at puck.nether.net] On Behalf Of Andy Harding
> Sent: Thursday, March 03, 2011 10:07 AM
> To: David Ball
> Cc: juniper-nsp at puck.nether.net
> Subject: Re: [j-nsp] BFD timers for OSPF - MX80 - 10.3R2.11
>
> We are using bfd on mx80 with 300ms timers and no problems. Only 2 or 3 sessions per box however.
>
> --
>
> Regards
>
> Andy Harding
> Internet Connections Ltd
>
> Phone: 0870 803 1868
> Mobile: 07813 975459
> Fax: 0870 803 1781
> Web: www.inetc.co.uk
> Email: andy at inetc.co.uk
>
> On 3 Mar 2011, at 17:53, David Ball <davidtball at gmail.com> wrote:
>
>>  Ah, that might help explain it.  And shame on me for not checking
>> 'sh pfe statistics traffic protocol bfd', which of course shows none
>> received or absorbed.
>>  I'll only have 2 sessions on each MX80, so I think I might leave it
>> enabled, but may toy with the interval.  I'm expecting the control
>> plane to be kinda bored on these guys, so we'll see what it can
>> handle.
>>  Thanks, Egor.
>>
>> David
>>
>>
>> On 3 March 2011 10:42, Egor Zimin <lesnix at gmail.com> wrote:
>>> Hello, David
>>>
>>> It looks like BFD implementation in MX80 is not distributed. At this
>>> moment I have a case in JTAC. The case is opened yet, however, it
>>> _looks_like_ bfd is not distributed.
>>> Probably because of this BFD echomode is not supported. And using 30ms
>>> timers for BFD ControlPackets can be not so easy task for RE's CPU.
>>>
>>> Because of this I don't see much sense to use BFD on MX80 at this moment.
>>>
>>> 2011/3/3 David Ball <davidtball at gmail.com>:
>>>> MX80s running 10.3R2.11
>>>>
>>>> For those of you using BFD for OSPF, how low have you been able to
>>>> set your minimum-interval timer?  I have a pair of MX80s connected via
>>>> XFPs and 1m patch cables and with my hellos set to 30ms and multiplier
>>>> set to 3, I'm seeing failures.  I haven't disabled distributed ppm.
>>>> Moving to 50ms hellos seems to settle things down.  The reason I'm
>>>> wondering why I can't get away with lower timers is because when
>>>> Juniper proof-of-concepted (yeah, that's a verb) Trio for us (albeit
>>>> using MX960s), they used 15ms hellos with a multiplier of 3.
>>>>
>>>> Mar  3 10:06:06  router bfdd[1129]: BFDD_TRAP_STATE_DOWN: local
>>>> discriminator: 1, new state: down
>>>> Mar  3 10:06:06  router rpd[1257]: RPD_OSPF_NBRDOWN: OSPF neighbor
>>>> 172.16.1.22 (realm ospf-v2 xe-0/0/2.0 area 0.0.0.0) state changed from
>>>> Full to Down due to InActiveTimer (event reason: BFD session timed out
>>>> and neighbor was declared dead)
>>>>
>>>>
>>>> me at router> show configuration groups bfd-defaults-core-ospf
>>>> protocols {
>>>>   ospf {
>>>>       area 0.0.0.0 {
>>>>           interface <*> {
>>>>               bfd-liveness-detection {
>>>>                   version automatic;
>>>>                   minimum-interval 30;
>>>>                   multiplier 3;
>>>>                   full-neighbors-only;
>>>>               }
>>>>           }
>>>>       }
>>>>   }
>>>> }
>>>>
>>>> me at router> show configuration protocols ospf area 0.0.0.0
>>>> interface lo0.0 {
>>>>   passive;
>>>> }
>>>> interface xe-0/0/2.0 {
>>>>   apply-groups bfd-defaults-core-ospf;
>>>>   node-link-protection;
>>>> }
>>>> interface xe-0/0/3.0 {
>>>>   apply-groups bfd-defaults-core-ospf;
>>>>   node-link-protection;
>>>> }
>>>>
>>>>
>>>> David
>>>> _______________________________________________
>>>> juniper-nsp mailing list juniper-nsp at puck.nether.net
>>>> https://puck.nether.net/mailman/listinfo/juniper-nsp
>>>>
>>>
>>>
>>>
>>> --
>>> Best regards,
>>> Egor Zimin
>>>
>> _______________________________________________
>> juniper-nsp mailing list juniper-nsp at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/juniper-nsp
>
> _______________________________________________
> juniper-nsp mailing list juniper-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/juniper-nsp
>