Migration Assistant between PowerPC and Intel

Where does Apple recommend using PowerPC to Intel migration with the Migration Assistant?

Where do they say not to?

http://support.apple.com/kb/HT3322 only states: *+If you need to transfer your files and important settings from an older Mac to a new one, you can use Migration Assistant.+* There's nothing in the document that precludes using it from a PPC to an ICBM (Intel-chip-based Mac).

Additionally, these fast start guides suggest doing it on first boot using the Setup Assistant:

http://support.apple.com/kb/HT2054
http://support.apple.com/kb/HT2347
http://support.apple.com/kb/HT2788

Then there are these migration tips:

http://support.apple.com/kb/HT3231
http://support.apple.com/kb/HT1291

And, finally, for windoze users:

http://support.apple.com/kb/HT2518

I've successfully used it from my unsupported G4 to the new iMac ICBM without issue. Additionally, my son-in-law did that successfully from an eMac running Panther to a new iMac ICBM. I've found it's easier to transfer from a PPC clone on a FWHD, than hook up the PPC to the ICBM, but both have worked successfully.

a brody wrote:
Where does Apple recommend using PowerPC to Intel migration with the Migration Assistant?

A better question would be where does it recommend against this? Can you show me one reference in any Apple literature that says Migration Assistant is intended only for like-CPU to like-CPU use?

Does the knowledgebase article actually say it should be used in such a migration? I haven't seen that.

I'm not sure which knowledgebase article you refer to, but several explicitly mention migrating applications from PowerPC-based Macs to Intel-based ones using using Migration Assistant or Setup Assistant. (See for example Intel-based Mac: Some migrated applications may need to be updated.)

Does the program itself actually say it is ready to be used between PowerPC and Intel Macs on the program windows itself?

The point is nowhere in the program or its help does Apple make any distinction between PPC-based & Intel-based Macs. If Apple did not intend for it to be used in this way, it seems very likely that this would be mentioned specifically, or that the app would simply ignore PPC Macs as potential migration sources, or something else equally easy to implement. As it is, the references are just to 'old Mac' & 'new Mac' or equally generic terms, with no indication that the CPU makes any difference.

Can you explain why two otherwise erase and installed systems with bare bones applications couldn't be migrated between in over 24 hours using the Migration Assistant? I tried it with my iMac Intel Core2Duo and iMac G5 1.8 Ghz.
It just sat there, with no progress in the migration.

No, given just the info you provided, I have no idea why it did not work. However, "it just sat there" isn't exactly a good example demonstrating that using MA for a PPC-to-Intel move "can lead to horrible issues later on," as you characterized it in the other thread, nor of the OS "malfunctions" mentioned in the user tip itself, whatever that vague phrase is supposed to mean.

With all due respect for your & Kappy's substantial expertise, this user tip seems predicated on the fact that a small sample of the user base have reported an assortment of problems after using MA in this way, largely unsubstantiated speculation about the possible reasons why these issues could occur, & the to me the dubious conclusion that most users will have one or more of these issues unless they avoid using MA for this.

I believe this is at least greatly overstated; that the risk is actually quite small of anything harmful occurring; & if something harmful does occur its cause is not in MA itself but lies elsewhere & should be addressed directly.

More to the point I've migrated a number of systems this way without any real issues, the caveat being that if you migrate this way you need to reinstall your applications to ensure that you don't end up running a PPC version of a binary via Rosetta because you originally installed the PPC rather than Universal version of the binary, or because no Universal version was available.

Flash is one big offender here.

Also, the OP should be told that Pro apps like Final Cut Studio WILL require you to reenter your registration information on the migrated machine, including your registration key.

So in general, the procedure that has always worked for me with great results is:

1) Use Migration Assistant to copy everything over
2) Reinstall all mission critical apps from their original media
3) Reinstall downloaded apps and plugins

Also, the "no progress in the migration" issue more often than not has been one of Apple's horrid 10.5.0 estimation mechanism of how long a migration would take. When I migrated from an iBook to an MBP, it said it would be "about a minute"; instead it actually took several hours - but it did complete.

When I recently did a migration to a machine that came preinstalled with 10.5.4, things seemed to go much more smoothly.

I used migration assistant to go from a Snowball iMac (800 G4) to a new Intel iMac last Fall, connected via Firewire cable. It took about 5 1/2 hours--the progress monitor stayed stuck showing "11 minutes remaining" for over 2 hours! I just turned my back on it and let it run. It finally completed and the Intel iMac has not had any problems. All the old Classic stuff came over and of course it won't run on the Intel, but it hasn't caused any problems.

Regarding the caveat about ensuring that you don't end up running a PPC version of a binary, note that this only applies to items not furnished in Intel or "Universal" versions with the new OS and that did not originally install universal versions on the old Mac (or if they did, you subsequently used something like Monolingual to remove the Intel resources).

Since many (if not most) third party applications, utilities, & plug-ins have been updated to be universal types since Apple's transition to Intel-based Macs, if you have kept your old Mac's software up to date, you will greatly reduce the number of applications, et al that you need to reinstall after using Migration Assistant.

Besides, it is not exactly the end of the world if some PPC binary is run via Rosetta. My Intel Macs are so much faster than my old G5 iMac that (for instance) the old PPC version of Flash Player renders Flash presentations much faster on the new Macs than the old one ever could -- so much so that I'm only now bothering to upgrade the new ones to the latest universal version, & that's only because William Kucharski's post reminded me that I had neglected to do so.

BTW, for users curious about what MA actually moved, you can consult /Library/Logs/SystemMigration.log with Console.app. By using the filter "Item will be copied," you get a handy summary of what (hopefully) was copied & where. Curiously, when I do that & search for Flash components, I get zero results, which suggests to me that my 2008 iMac came with at least the NP-PPC-Dir-Shockwave plugin already installed.

My one real complaint about using MA for PPC to Intel moves isn't actually with MA but with Spotlight: I haven't found a way to get it to show me just PPC applications, which would be very handy.

When I did this from my iMac G5 to my MBP it did take a while to do. But it worked perfectly, there is no problem going between two different architecture types.

These are basically the same issues that can occur after an Archive & Install: some applications require newer frameworks than the new OS contains. Obviously, it would be nice if Migration Assistant noticed that the framework from the source Mac was newer than the one on the recipient Mac & replaced it, but the symptoms & solution is essentially the same as in Intel-based Mac: Some migrated applications may need to be updated.

Overall, I can see this as an at least sometimes desirable conservative behavior of MA -- I'm not sure I would want it to replace newly created frameworks with any that might be corrupted from another Mac, at least without more error checking than it probably is feasible to include in the app.

Also, I don't see how not migrating the necessary framework could slow down the migration process anywhere near as much as you described. Without much to go on, my guess would be something in the source Mac wasn't right (maybe a file system error?), or maybe in the Firewire connection.

If it is still around, perhaps the migration log file could offer some clue....