Re: [sami] Welcome to SAMI and something you may like to know.

[Melinda Shore <[e-mail]>]

On 08/17/2011 12:58 AM, Yingjie Gu(yingjie) wrote:
> So,pehhaps we can define the scope as such:A layer 2 subnet with good enough
> performance which makes the hot migration successful."

I think it would be worthwhile, should this work go forward, to
describe what happens (or what should happen) if the failover
is unsuccessful - things like at what point state transfer happens.
It seems to me that there's a pretty clear decision point around
whether or not you wait until the failover is complete and
successful (can you know if it's successful before it's complete?)
before transferring middlebox state, and I definitely would
not like to see that dismissed as out-of-scope before any work
is even chartered.

I'd also stay away from "good enough performance" - not really
sure what that means in a technical context.

Scope would be something along the lines of:

    The work will cover transfer of associated middlebox state [and
    i'd probably enumerate examples - probably includes firewall
    pinholes, probably does not include layer 3 routing] needed to
    maintain existing network flows as a network services fail
    over to a hot standby.  Doing the hokey-pokey is out-of-scope.

That needs a lot of work and it would need definition of terms
like "hot standby" and "middlebox," etc., but it describes what
will be included in the work and what will not.

Melinda