[OpenAFS] Re: Redundant Internet links

Derrick Brashear shadow@gmail.com
Thu, 16 Dec 2010 11:31:48 -0500


On Thu, Dec 16, 2010 at 11:12 AM, Andrew Deason <adeason@sinenomine.net> wrote:
> On Thu, 16 Dec 2010 01:55:31 +0100
> Jaap Winius <jwinius@umrk.nl> wrote:
>
>> Regarding the use of the redundant links in the above scenario, would
>> it be possible -- desirable or wise even -- to present the clients,
>> which have empty CellServDB files, with DNS AFSDB RRs that point to
>> five different IP addresses: one internal for the local machine and
>> four external for the two remote ones?
>
> Is the "internal" address only routable from that site? Clients (OpenAFS
> clients, anyway) will try to ask the dbservers for which dbserver is the
> sync site when performing a write operation to whatever db; I'm not sure
> how they behave if a client gets an address it doesn't recognize as an
> answer.

You can simulate this easily with no-AFSDB, and a sync site on a
not-in-CellServDB server.
You end up with UNOTSYNC, iirc, but basically "you lose"

> dbservers are different, though; the specification in CellServDB affects
> the voting algorithm

Only for the server config of course, but yeah.