1. I burn a dmg to a dual-layer DVD using Disk Utility. (Edit: The source disc had already passed all my tests.)

2. I opt for "Verify," and it passes.

3. Disk Utility tells me that the disc was successfully burned (or some-such).

4. I run Disk Utility > Images > Checksum > CRC-32 image checksum, and the source and destination checksums match.

Quote:
Disk Utility > Help:

Verifying files are copied correctly from a disk image

After you use a disk image to restore a disk or burn a CD or DVD, you can use checksums to verify that the files were copied correctly. A checksum is a calculation of all the data on a disk or disk image that yields a specific number.

You can compare this number with the checksum of the source image. If the two numbers are the same, the files were copied exactly.

5. As a final test, I run "Duplicate" in Finder, and it spits out an I/O error (which I confirm with a second run, because I've gotten false negatives).

Are the results of step 4 inconsistent with those of steps 2 & 3, or am I misunderstanding what "Verify" and "Checksum" actually do?

Thanks.

Last edited by artie505; 02/15/11 11:05 AM. Reason: Add info, clean up
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