thanks for the reply: After posting I read articles realizing that there is no migration path available from 6.6 to 7.1 at this time. I thought I came across an article that there was one but it was in error. My posting was a little hasty and I apologize for not doing a careful research before hand. But I suffered no loss myself because I attempted the upgrade on a separate machine and all I had to do was to get the old system back online and re-register it. It seems that a manual migration is the only viable way right now and I wonder whether it is really worthwhile considering that my 6.6 system is working flawlessly...

As far as I know, for the moment you cannot yet back up in 6.x then restore to 7.x. The devs said they were working on it but I've no idea how they are getting on. A few weeks ago another poster did the same and strongly recommend you not to do it as it leaves too many problems - as you've found out. There has never, in any case, been an upgrade route from 32bit to 64bit.

If you wanted to keep the old Ethernet naming convention, have a look at this article, but although it suggests you can still use udev, when I had a little look at udev for some other reason, it was structured very differently from 6.x. Presumably just removing the kernel parameter biosdevname or setting it to 0. If you read the article I linked to and go to the next page it gives some help with udev.