I think you replied to your own question :) When running from a chroot jail, the filesystem root path is the chroot jail's path. When running from outside a chroot jail, the filesystem root path is the real /. So we are talking about what is conceptually two different filesystem structures, with different absolute paths to the same file, ergo the absolute path won't cut it.
That said, we do store the filename and do look for that filename in the configured output directory of the profile which was used to take the backup. As long as it's configured correctly (i.e. PHP code running in the web context can access it) Akeeba Backup will figure out that the file exists and not assign an obsolete status.
So, to recap:
- Your output directory must be accessible from PHP code running in the web context
- It must have 0755 permissions or greater
- The file must have 0644 permissions or greater
In your case, I think that the problem is in the output directory definition of that particular profile.
Nicholas K. Dionysopoulos
Lead Developer and Director
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