On Thu, 2009-10-29 at 07:25 -0700, Greg KH wrote: > On Thu, Oct 29, 2009 at 08:11:25AM -0500, Matt Domsch wrote: > > Netdev team - are you in agreement that having multiple names to > > address the same netdevice is a worthwhile thing to add, to allow a > > variety of naming schemes to exist simultaneously? If not, this whole > > discussion will be moot, and my basic problem, that the ethX naming > > convention is nondeterministic, but we need determinism, remains > > unresolved. > > I'm still totally confused as to why you think this. What is wrong with > what we do today, which is name network devices in a deterministic > manner by their MAC in userspace? That name goes into the kernel, and > everyone uses the same name and is happy. > > If you don't like naming by MAC, then pick some other deterministic > naming scheme that works for your hardware and write udev rules for it. > > You could easily name them in a way that could keep the lowest number > (eth0) for the lowest PCI id if you so desired and your BIOS guaranteed > it. > > This way the kernel has only one name, and so does userspace, and > everyone is happy. I thought there was a general trend in udev development to provide default rules that work for almost everyone, so few users/administrators need to override or add to them. Compare disks and net devices: 1. Stable kernel device id Disks: block device number Net devices: ifindex 2. Unique identifier (across reboot) Disks: label or UUID (each with limitations) Net devices: (MAC address, subtype) 3. Name assignment mechanism Disks: kernel suggests a name; udev can assign any number Net devices: kernel assigns a single name; udev can override it 4. Default name assignment policy Disks: names disk by device path (id), label and UUID Net devices: assigns arbitrary stable names per (MAC address, subtype) 5. Naming by users Disks: user can identify by any method without having to choose on a system-wide basis Net devices: user must identify by single name; policy can be overridden on a system-wide basis I fully understand the technical reasons for differences 3-5, but why should users have to put up with it? Ben. -- Ben Hutchings, Senior Software Engineer, Solarflare Communications Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked. -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
