Re: [sami] First SAMI email in the new year, can we go further? Look forward to your opinions.

Benson Schliesser <bschlies@cisco.com> Fri, 02 March 2012 02:30 UTC

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From: Benson Schliesser <bschlies@cisco.com>
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Date: Thu, 01 Mar 2012 18:30:45 -0800
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To: sami@ietf.org
Subject: Re: [sami] First SAMI email in the new year, can we go further? Look forward to your opinions.
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On Mar 1, 2012, at 9:02 AM, <david.black@emc.com> <david.black@emc.com> wrote:

>> I think so, and there's no doubt it would be helpful to be clearer about
>> that going forward.  However, my understanding that while the VM image
>> would be moved (craploads of kernel state - file tables, page tables,
>> all that crap), network activity would have to be quiesced first.  
> 
> That understanding is incorrect - network activity is not quiesced.  A
> gratuitous ARP or RARP is issued after the migration, and some inbound
> packets may get dropped because they are delivered only to the source
> location of the migration.

Right. Minor packet loss is possible, but the VM migration is designed so that e.g. established TCP connections don't fail.

Like Thomas, I see that there is something to be done here. But I also agree that we need to figure out the use-cases first, driven by real operational requirements. It might help if we started talking about use-cases for VM migration - yes it's possible, but why do people use it? - so that we can figure out if any of them inform the discussion of state migration.

Further, are there any non-VM mobility use-cases for state migration? I can imagine a few, but again I want to make sure they're being driven by operational needs rather than mere possibility.

Cheers,
-Benson

[sami] First SAMI email in the new year, can we g… Yingjie Gu(yingjie)
Re: [sami] First SAMI email in the new year, can … Thomas Narten
Re: [sami] First SAMI email in the new year, can … Melinda Shore
Re: [sami] First SAMI email in the new year, can … Thomas Narten
Re: [sami] First SAMI email in the new year, can … Melinda Shore
Re: [sami] First SAMI email in the new year, can … Thomas Narten
Re: [sami] First SAMI email in the new year, can … david.black
Re: [sami] First SAMI email in the new year, can … Juergen Schoenwaelder
Re: [sami] First SAMI email in the new year, can … zhangyunfei
Re: [sami] First SAMI email in the new year, can … Benson Schliesser
[sami] 答复: First SAMI email in the new year, can … Dacheng Zhang(Dacheng)
[sami] 答复: First SAMI email in the new year, can … Dacheng Zhang(Dacheng)
Re: [sami] First SAMI email in the new year, can … david.black
Re: [sami] First SAMI email in the new year, can … Melinda Shore
Re: [sami] 答复: First SAMI email in the new year, … Juergen Schoenwaelder
[sami] 答复: Re: First SAMI email in the new year, … Yingjie Gu(yingjie)