Re: [MirageOS-devel] irmin + mirage-vnetif + alcotest + good ol' arp

[Magnus Skjegstad <magnus@xxxxx>]

On Thu, 9 Apr 2015, at 22:39, Mindy wrote:
> 
> On 04/09/2015 07:30 PM, Thomas Gazagnaire wrote:
> >> I'm not that far into doing anything interesting with this pile of code, 
> >> but I wanted to solicit your thoughts and feedback given all the mumbling 
> >> and general noise-making about testing we've been doing.
> >>
> >> Thanks for your consideration and support. :)
> > That's awesome!

Yes - very cool!

> > I haven't checked the code yet, but is the mapping bi-directionnal, i.e. 
> > can you modify the ARP table in the Git repository, commit and then it's 
> > picked up by the ARP code?
> Yes, it should work this way (once there's more code in place).
> > If yes, a good way to stress test the system is to (1) generate a big 
> > history of stuff and (2) use git reset --hard to revert to arbitrary points 
> > in the past (which are supposed to be consistent) and check that nothing 
> > breaks badly (this is a good test for intermediate caches for instances). 
> > In a distributed settings, if you keep track of the state of multiple 
> > unikernels, you can try to verify that global invariants (involving 
> > multiple unikernels) still hold.
> Ah, that's a good suggestion.  Thank you!
> >
> > Not related to testing, but that would be cool to find a clever use for git 
> > pull/push between unikernels (replacing ARP broadcast maybe?)
> I'd been thinking about (or maybe remembered talking about with someone 
> else?) pre-seeding newly booted unikernels with caches reflecting the 
> current state of the local network, which is a less general case of what 
> you propose.

One use case for this could be to let something that manages unikernels
(e.g. Jitsu) update ARP tables in running unikernels. Jitsu already
knows the MAC address and IP of all the unikernels it controls, so it
could keep the tables up to date automatically and add/remove entries as
unikernels are booted/destroyed. This could also potentially reduce the
unikernel boot time if we can add ARP entries for gateways etc in
advance.

Magnus

_______________________________________________
MirageOS-devel mailing list
MirageOS-devel@xxxxxxxxxxxxxxxxxxxx
http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel