This prevents the occurrence of the temporary network interface names, when udev has to rename the network interfaces. Remember the "eth0-rename" or "eth0-eth1" temporary names?

Ah, I should add the following: These temporary names were not "unique" enough, but using the IFINDEX should be.

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When udev renamed network interfaces and encountered a naming conflict, it renamed the interfaces to "<initial name>-<wanted name>". This name might also be not unique. So udev now uses the unique interface index for renaming and temporarily renamed interfaces now have the name "rename<ifindex>".

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@@ -1 +1 @@
-When udev renamed network interfaces and encountered a naming conflict, it renamed the interfaces to "<initial name>-<wanted name>". This name might also be not unique. So udev now uses the unique interface index for renaming and temporarily renamed interfaces now have the name "rename<ifindex>".+When udev renamed a network interface and encountered a naming conflict, it renamed the interface to "[initial name]-[desired name]". Sometimes, this name was not unique and the naming conflict persisted. This bug has been fixed, udev now uses the unique interface index for renaming, and temporary names for interfaces are now of the following format: "rename[ifindex]".

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2011-1649.html