0 کاربر و 1 مهمان درحال مشاهده موضوع.
You can delete B without affecting C, or you can delete A without affecting B or C because of the "hard link" method used. Simplifed explanation (skipping over the inodes): the data gets stored on the first snapshot, and the directory entries in the backup are hard-linked to the data files. On subsequent incremental backups, new files are added with their new hard links - for unchanged files, hard links are added in the new snapshots linking to the original data from the first snapshot. A data file which is unchanged over the course of a dozen snapshots will have a dozen hard links to it. If the next snapshot does not contain that file because it has been deleted from your system, then no more hardlinks to that file data will be added, but the data will remain on the backup until there are no more hard links to it from previous snapshots - you would have to delete all snapshots which contained that file before the data would disappear.Assume A has files 1, 2, and 3. There are hard links from backup A to the data of these each of these files.A: 1, 2, 3Now add a file 4 and delete file 2 and make backup B. Now files 1 and 3 have two hard links (A and B), file 2 has one link (A) and file 4 has one link (B).B: 1, 3, 4Backups A and B appear to be complete backups at the time they were made. Now modify file 1 to 1' and make backup C. File 1 has two links (A and B), file 1' has one link (C), file 2 has one link (A), file 3 has 3 links (A, B, C), and file 4 has 2 links (B and C).C: 1', 3, 4But there is only one copy of the data for each of the 5 files. The data for a file remains until all the hard links to that file have been removed. Delete backup A and file 2 will no longer have any links so file 2 data goes away. But there are still links to files 1, 1', 3, and 4. Backup B is a still a complete backup and so is C.