Summary of "SA Lab Exp 8 Part 2"

File Management and Backup in Unix-like Systems

This segment explains commands and methodologies related to file management and backup, focusing primarily on the cpi command and the dump/restore commands.

Scientific Concepts and Discoveries Presented

File Merging and Extraction Using the `cpi` Command

CPI stands for Copy Copy Out.
It is used to merge multiple files into a single archive (e.g., tar file) or extract files from such archives.
cpi operates in three modes:
- Input mode (-I): Merges files into an archive.
- Output mode (-O): Extracts files from an archive.
- Pass mode (-P): Copies files from one directory to another without archiving.
File lists for archiving or copying are created using the find command.
Proper use of input/output redirection and pipe symbols is necessary.
The -H option specifies the archive format (e.g., TAP, ZIP).

Backup and Restoration Using `dump` and `restore` Commands

dump backs up entire file systems.
restore recovers files from backups created by dump.
Two types of backups:
- Full backup (level 0): Backs up all files.
- Incremental backup (levels 1-9): Backs up only files changed since the last backup.
Backups are recorded sequentially as records, historically stored on tape files.
Important dump command options:
- -0 for full backup.
- -F to specify the file name to dump to.
- -u to update the backup record.
- -b to specify block size.
- --list to list file systems available for backup.
- --estimate to estimate the space required for backup.
Incremental backups save time and space by only backing up changes since the last full or incremental backup.
Multiple directories can be backed up in one command.