Re: [OSPF] [Adj-SID Flags] Regarding newly added 'P' flag

Peter Psenak <ppsenak@cisco.com> Thu, 02 March 2017 09:26 UTC

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Date: Thu, 02 Mar 2017 10:26:09 +0100
From: Peter Psenak <ppsenak@cisco.com>
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To: Veerendranatha Reddy Vallem <veerendranatharv@huawei.com>, "draft-ietf-ospf-ospfv3-segment-routing-extensions@ietf.org" <draft-ietf-ospf-ospfv3-segment-routing-extensions@ietf.org>
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Subject: Re: [OSPF] [Adj-SID Flags] Regarding newly added 'P' flag
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Hi Veerendranath,

On 02/03/17 05:53 , Veerendranatha Reddy Vallem wrote:
> Dear Authors,
>
> As per my understanding ā€˜Pā€™ flag is used to avoid Adj-SID value  change
> in forwarding plane and during segment routing path calculation by
> controller  for interface flapping or switch over cases.

for any case, even for router reload, etc.

>
> The Adj-SID value may change if adjacency gone down for longer period
> (say 10 min) and come up, even P flag is set in previous advertisement.

no. If the P flag is set, the Adj-SID should never change, unless 
specifically requested by the operator.

thanks,
Peter


>
> Please help me to know if any other use cases for setting P flag in Adj-SID
>
> Regards,
>
> Veerendranath
>