[RFC] dropping network hotplug support from network service

[Bill Nottingham]

Don Dutile (ddutile at redhat.com) said: 
> On 06/20/2011 05:09 PM, Bill Nottingham wrote:
> > I'm considering drop the network hotplug support from the 'network'
> > service. This is the code that would automatically run ifup when a new
> > network device appeared, if there was a configuration for it.
> >
> > The supported solution would be to use NetworkManager for these usage
> > cases (or wicd, or netplugd, or conman...) Alternatively, just run
> > ifup yourself.
> >
> > Currently, this would happen in the following cases:
> > 1. USB and/or expresscard hotplugged ethernet/wireless
> > 2. PCI hotswap of a network card
> > 3. Runtime addition of network interfaces in virtual system
> > 4. Admin manually removes and reloads a driver module
> >
> > For #1, those systems are generally better served by NM.
> > For #2, this is something with such heavy admin interaction that I
> > would suspect that it would be preferred to handle it manually. (Also,
> > swapping hardware likely invalidates the configuration in any case.)
> > For #3, you're unlikely to have a configuration written for a freshly
> > available device.
> sorry, I don't understand this statement....
> but has me worried for virt hot add/remove of assigned devices

Essentially, hot-adding a virtual device would not bring the device
up automatically if you're using the old network service; you'd have
to run 'ifup' by hand.

> > For #4, bringing up the device automatically can cause more issues
> > than it solves. (We've seen this happen for vlans, for example.)
> This is done all the time (on KVM hosts) to take down PF driver & load 
> PF+VF drivers for SRIOV-capable devices.

This would be a different device with a different hardware address,
correct?

Bill