On 12/14/2011 04:47 PM, Helmut Drodofsky wrote:

Hello,

with CentOS 6, my new server created an UUID entry in ifcfg-eth0 - additional to HWADDR entry.

Up to CentOS 5 the connection to the netwark card was defind only by HWADDR.

Now I have a new network card. How can I get the correct UUID?

The server connects correct the network with the updated HWADDR without any UUID. Why do I need an UUID?

Thank you for help in advance.

I'm only speculating here since I did notice the new UUIDs but haven't had to deal with them so far but my guess is that they provide a way for the to uniquely identify the logical interface and have nothing to do with the phyiscal interface itself. For example if you configure bridging you need to tell the interface the bridge they belong to. If you use the name "br0" for example and later decide to rename it to "bridge0" then you also have to fix all references. If instead you reference the UUID then that is not necessary and you can rename them as you please without breaking any references.

Again this is speculation on my part based on how/why the UUIDs for disks where introduced.

Regards, Dennis