You're welcome, DFORION, and I'm glad you were able to retrieve your data.
DAO is probably the most straightforward method to burn a disc and is also the method most likely to be compatible with other systems. When I have a disc full of material (either physcially full or logically full - e.g. pictures from vacation 2003) I always burn it DAO. But I also use multi-session TAO burns as well. Once I gave up on Nero's auto-refresh option as too confusing for me and got into the habit of always importing the last session when burning a new session, I haven't had any problems.
I wouldn't say that multi-session burning is fragile (I reserve that adjective for packet writing), but I do agree it can be a bit unpredicatable. Of course, that isn't meant to imply that Nero is randomly selecting files for inclusion/exclusion when importing previous sessions. It doesn't. But unless you take special care to be aware of exactly what options you have selected and how they will interact with what you have already burned on the CD-R and what is on the hard drive, it can lead to unexpected results.
This is what I normally do when burning multi-session discs. Assume I have the following folders on my hard drive that I wish to back up:
- Code: Select all
-mystuff-+-photos
|
+-software
Within the photos folder are a bunch of jpeg files that I am in the middle of cropping, adjusting colors and otherwise retouching. Within the software folders are a bunch of source files for programs I am writing that, since I make lots of mistakes, I am constantly changing to eliminate bugs. Note the theme for both of these folders: I am making lots of changes to many files.
When I burn my first session, I could just burn the folders as is so that I would have this on the CD-R:
- Code: Select all
CD-R_root-+-mystuff-+-photos
|
+-software
However, if I did this I would run into trouble when I wanted to store my next backup of these same files:
- Code: Select all
CD-R_root-+-mystuff-+-photos
| |
| +-software
|
+-mystuff-+-photos
|
+-software
Obviously this wouldn't work because there are two folders with the same name in the CD-R root folder. To get around this I always rename the top-level folder of my backup with the date of the backup. For example, after burning a backup on March 1 and March 5, I would have this:
- Code: Select all
CD-R_root-+-mystuff_2004_03_01-+-photos
| |
| +-software
|
+-mystuff_2004_03_05-+-photos
|
+-software
This gives me several advantages. First and foremost, I can keep multiple copies of the same folder on the same CD-R without them interfering. Second, I have a complete snapshot of all files at each backup so I don't have to try to figure out which version of one file went with which version of another file. Third, I can easily read the dates of backups so if I need to revert to an earlier version I can easily find it. Finally, because I includ the date in a yyyy_mm_dd format with leading zeros, alphabetical order is the same as time order, making it easy to browse directory listings. Note that I chose to append the date so the sort order goes by folder name first and then date, but you could also choose to prepend the date so that the sort order is date first and folder second.
Now, my method works well for me because I typically have many changed files per backup, and I like having a complete snapshot of all files at every backup. But it has drawbacks as well. Probably the most serious is that it doesn't use CD-R space very efficiently if you only have a few files that change between backups or you just want to add a few files. Burning second copies of all the unchanged files to include a few changed or new files is wasteful. It would be more efficient to just link to the unchanged files and burn fresh the new and/or changed files.
So, in the end you have to look at your specific situation and pick the right strategy to suit it. That strategy might be mine, some variation of it, a strategy you devise yourself, or even Nero's auto-refresh if you thoroughly understand what it does and it matches what you want to do. There are as many valid ways to organize backups as there are computer users.
As for CD-RW working better with CD-R when it comes to multi-session burning, no that is not the case. Your trouble when attempting to import the final session and finalize the disc was probably the result of a bug in Nero, using two different burners or versions of Nero, a defect in the CD-R, or a glitch from the burner. I don't believe your problem is indicative of any inherent weakness in CD-R media used for multi-session burning. Assuming healthy CD-R and CD-RW media, there isn't any difference between them and both will work equally well with multi-session burning.
If you were to force me to say which is more reliable with multi-session burning I would say CD-R simply because CD-R is more reliable at the physical layer in general. Also, there is no danger of physically erasing data on a CD-R while there is with CD-RW. Oops! Did that pop-up window I just clicked "yes" on ask me if I wanted to blank a non-empty disc?!? I thought it was asking if I wanted to continue the session from a non-empty disc...
Oh, and one more thing. Because I have found CD-R to be more reliable and have a longer lifetime than CD-RW, I recommend CD-RW only for short-term backup of non-critical files and copying files from one place to another. I would never commit the sole copy of a valuable file to a CD-RW disc, or to any one piece/type of media for that matter.
cfitz
