[Engine-devel] Network Wiring

[Alona Kaplan]

> > <snip>
> > 
> > > > > purge a network while it is connected to VMs: Link-Down on
> > > > > all
> > > > > nics
> > > > > and connect to the empty/no network. (Yes I know, it's not
> > > > > par
> > > > > of
> > > > > the
> > > > > feature, but you know someone will ask for it soon :))
> > > > 
> > > > It should not be hard to implement; In
> > > > http://wiki.ovirt.org/wiki/Feature/DetailedNetworkWiring#New_API
> > > > I
> > > > suggest passing
> > > > no 'network' element to mean "connected to nothing".
> > > >
> > > I don't really understand why changing the link state to down is
> > > not enough?
> > > What is the added value of connecting "unwired" nic to a none
> > > network?
> > 
> > It is not a big deal of a difference, but the semantics of having
> > no
> > network is clear: you can run the VM if networks are missing, you
> > can
> > remove a network when the VM is running. When a VM is associated to
> > a
> > network, but its link state is down, the "right" semantics is more
> > vague.
> 
> Indeed :)
> 
> Plus consider the use case of hooks providing the networking - they
> still need the engine to assign the MAC and type (like the CISCO
> hook).
> If you force a logical network on each nic, it means you have to
> invent a dummy LN and define it as non-required and set the global
> config to allow VMs to run on hosts that do not have this networks -
> Too messy. Though sometimes desirable since the network name may be
> a hint to the hook, there are cases it's not.
> 
> -> No LN means this VM can run on any host! with implicit assumption
> that someone else takes care of connecting it to the proper network.
> 
> Note that in this case you may still want the network with link state
> up and be allowed to bring the link up/down so it's for sure not the
> case as 'unwired/link down but connected to arbitrary network'
> 

I"ve added "none" network option to the wiki.
Any more comments? Do we have green light to start working on the feature?