[rrg] FYI: Architectural Implications of Locator/ID Separation - draft-meyer-loc-id-implications

[William Herrin]

On Mon, Dec 22, 2008 at 3:23 PM, David Meyer <dmm at 1-4-5.net> wrote:
>        OTOH, what would be helpful would be for you and/or Robin
>        to describe  *the mechanism and how it works, in detail*
>        that you are proposing, then show how it solves the
>        simple example problem in Section 3 (Figure 1) for the
>        draft.

David,

On second thought, my external manager in TRRP doesn't take any action
at all to solve figure 1.

I have two map servers (DNS servers) one using a BGP PA address at A
and one using a BGP PA address at B. This is a typical redundant
configuration for DNS servers.

My map entry on the server at A is different than my map entry on the
server at B. This is unusual for DNS servers today but not unheard of.
The map at A gives La priority. The map at B gives Lb priority.

S1 found La by following the DNS root down to my map server at A and
querying my map there. When A becomes unreachable to C, packets from
S1 stop reaching S0. A few seconds to a minute later, the map TTL
expires. S1 refreshes the map from my map servers.

S1 can't get a response from the map server at A so it tries the one
at B (normal DNS resolver behavior). The server at B provides a map in
which Lb has priority. Since S1 can reach Lb, communication between S1
and S0 resumes.

Have fun,
Bill Herrin




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William D. Herrin ................ herrin at dirtside.com  bill at herrin.us
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