On 5/3/2011 10:40 AM, Steve Clark wrote:
The numbers chosen in the eth? scheme are more or less randomized even on identical hardware, so it is pretty much impossible to prepare a disk to ship to a remote site and have it come up working unattended or clone disk images for a large rollout. If this gives predictable names in bios-detection order it will be very useful. Remote-site support is expensive and typically not great at the quirks of Linux distributions that you need to know to do IP assignments.
In my experience with Linux over the last 3 years using Centos and RH I have never seen the ethn device numbering change, and it always corresponds to the hardware vendor marking on the units we use.
We create images and ghost them onto various hardware platforms. I just make sure I remove the net persistent rules and the ifcfg-ethn stuff and they are then redetected in the correct order.
I was able to do that with the 2.4 kernel, but it hasn't worked for me across an assortment of hardware with Centos 5.x. Even if I try to pre-set the HWADDR in the ifcfg-eth? files when I know them ahead of time, there's a fair chance that moving the disk will trigger a kudzu run that renames my prebuilt files and replaces them with a default dhcp set. The numbers tend to flip in pairs, though, probably corresponding to the grouping on the motherboard and cards, so if you only have 2 they might stay fixed.