Release Notes for buster: 70-persistent-net-rules still supported?

[Michael Biebl]

Am 03.07.19 um 18:48 schrieb Justin B Rye:
>> As said, net.ifnames=0 does not enforce the old naming scheme, it means
>> use the kernel provided names.
> I don't follow.  Surely the old naming scheme *is* to use the
> kernel-provided names?  Where did names like "eth0" come from if not
> the kernel?
> 

Not quite. The old scheme (let's called it 70-persistent-net.rules for
that matter) used the same name space as the kernel (i.e. eth* and
wlan*) but it bound it to the MAC address.

So, an interface could be called eth0 by the kernel but
70-persistent-net.rules would map this to eth1 (this can happen if
70-persistent-net.rules already had an old eth0 entry from a card that
no longer existed).

The result is that 70-persistent-net.rules renames eth0 to eth1.
This is one, if not the most problematic aspect of the old scheme as it
was using the kernel name space to pick the new names from. It's not
hard to see that this is riddled with race conditions if you have
multiple interfaces.

Now, with net.ifnames=0 we don't do any renaming in user space at all.
We just take the interface names that are given to us by the kernel.

-- 
Why is it that all of the instruments seeking intelligent life in the
universe are pointed away from Earth?

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <http://alioth-lists.debian.net/pipermail/pkg-systemd-maintainers/attachments/20190703/ef746d17/attachment-0001.sig>