why 2 addresses?

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malicks

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Dec 21, 2009, 6:31:10 PM12/21/09
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I am curious why you chose to advertise two Anycast addresses instead
of one? Do certain client resolver libraries behave differently when
configured with one address vs. a list?

Prem Ramaswami

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Dec 21, 2009, 8:30:15 PM12/21/09
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it's often best to have a primary and secondary in case of inaccessibility to one of the routes.

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malicks

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Dec 22, 2009, 2:00:40 AM12/22/09
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But IP Anycast should take care of that (inaccessible routes), so a
single Anycast address should still give you network-level redundancy.

On Dec 21, 7:30 pm, Prem Ramaswami <pr...@google.com> wrote:
> it's often best to have a primary and secondary in case of inaccessibility
> to one of the routes.
>
>
>
> On Mon, Dec 21, 2009 at 6:31 PM, malicks <mali...@gmail.com> wrote:
> > I am curious why you chose to advertise two Anycast addresses instead
> > of one? Do certain client resolver libraries behave differently when
> > configured with one address vs. a list?
>
> > --
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> > You received this message because you are subscribed to the Google
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Alex Smith

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Dec 22, 2009, 7:10:51 AM12/22/09
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And then what happens if the route that 8.8.8.8 (8.8.8/24) is in stops getting announced but the route that 8.8.4.4 (8.8.4/24) is in doesn't? They are both separately advertised so the chances of *both* routes being withdrawn are highly unlikely.

Or if 8.8.8/24 started flapping and got damped... etc etc etc
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