Re: [OSPF] OSPF Link Overload - draft-hegde-ospf-link-overload-01

"Acee Lindem (acee)" <acee@cisco.com> Mon, 05 October 2015 13:48 UTC

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From: "Acee Lindem (acee)" <acee@cisco.com>
To: "Anil Kumar S N (VRP Network BL)" <anil.sn@huawei.com>, Pushpasis Sarkar <psarkar@juniper.net>, "Les Ginsberg (ginsberg)" <ginsberg@cisco.com>, Shraddha Hegde <shraddha@juniper.net>
Thread-Topic: OSPF Link Overload - draft-hegde-ospf-link-overload-01
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Date: Mon, 5 Oct 2015 13:48:11 +0000
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Cc: Hannes Gredler <hannes@gredler.at>, OSPF WG List <ospf@ietf.org>, Mohan Nanduri <mnanduri@microsoft.com>, "Jalil, Luay" <luay.jalil@verizon.com>
Subject: Re: [OSPF] OSPF Link Overload - draft-hegde-ospf-link-overload-01
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Anil, 

On 9/30/15, 1:25 AM, "Anil Kumar S N (VRP Network BL)"
<anil.sn@huawei.com> wrote:

>Hi All,
>
>In support of the draft : draft-hegde-ospf-link-overload-01
>Draft makes sense in below scenario I suppose, I could be wrong.
>
>Case where Router detectes some fault in link, would like to advertize
>link as unusable for a while.
>
>If any router using TI-LFA for FRR might be using this link for stiching
>P & Q-nodes. 
>Link Overload sub TLV might help LFA clacualting node to use some other
>link for that period of time.

It is already advertised at max-metric, for LFA/RLFA my implementation
(Ericsson) avoided using max-metric links…

Acee 


>
>Possibly router under maintainence could be refresh router LSA with out
>this link, Backward link check fails
>and link under maintaince will not be used. I think this would be treated
>as topology change which is not the case.
>
>I feel Overloading Node and Link are done for short period of time and
>might come handy while debugging/isolating network issues.
>
>Thanks & Regards
>Anil S N
>
>"Be liberal in what you accept, and conservative in what you send" - Jon
>Postel
>
>
>
>> -----Original Message-----
>> From: OSPF [mailto:ospf-bounces@ietf.org] On Behalf Of Pushpasis Sarkar
>> Sent: 30 September 2015 10:28
>> To: Les Ginsberg (ginsberg); Shraddha Hegde; Acee Lindem (acee)
>> Cc: Hannes Gredler; OSPF WG List; Mohan Nanduri; Jalil, Luay
>> Subject: Re: [OSPF] OSPF Link Overload - draft-hegde-ospf-link-
>> overload-01
>> 
>> Hi Les,
>> 
>> 
>> 
>> 
>> On 9/30/15, 9:45 AM, "Les Ginsberg (ginsberg)" <ginsberg@cisco.com>
>> wrote:
>> 
>> >><Shraddha>As I indicated before, max-metric can work in most common
>> >>scenarios but not all. There could be cases where an alternate path
>> >>cannot be found Satisfying the constraints so LSP remains on the link
>> >>undergoing maintenance since the link is still a last resort link.
>> >
>> >[Les:] Which seems to me to be exactly the definition of link of last
>> resort i.e. in the absence of any other alternative use the link
>> undergoing maintenance.
>> >??
>> [Pushpasis] What if the operator does not want any traffic on those
>> links at all? Should not there be a way to ensure that as well?
>> 
>> >
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