Backing Up and Restoring Data If you've worked with computers for any length of time, you've probably discovered why making regular backups is important. Specifically, if you haven't backed up your data, you're going to lose it.To back up data using tar:
- tar -czvf archive.tar.gz filesordirsWhere archive.tar.gz is the name of the archive you'll be creating, and filesordirs is a list of one or more files or directories to include in the archive.
Tracking Security Advisories US-CERT (U.S. Computer Emergency Readiness Team) tracks the spread of security exploits (including viruses, worms, Trojans, root compromises, and so on) around the Internet, their danger level, and the response, if any, of vendors, such as a patch or work-around. As a system administrator, you would be wise to pay attention to US-CERT in case any of the many new and exciting problems discovered almost weekly affect the software you're running.At the US-CERT Web site (www.us-cert.gov), you can find major announcements, notification of current security exploit activity, and information on how to prepare for and respond to problems (Figure 4.1).Figure 4.1. The US-CERT Web site tracks network-security issues worldwide. ), you'll get emails about new exploits and security patches. You'll also want to install any security patches for your operating system, servers (including Web, email, and FTP if you have them installed), and other software. The CERT advisories will almost always point you toward an appropriate patch. | The -czvf options are, in order: create an archive, compress the archive, be verbose, and store the archive data in the file specified by the next argument.
To restore data using tar:
- tar -xpzvf archive.tar.gzWhere archive.tar.gz is the name of an existing archive created with tar. This extracts the files and directories in archive.tar.gz into the current directory.The -xpzvf options are, in order: extract the contents of an archive, preserve ownership and permissions, read compressed archives, be verbose, and read the archive data from the file specified by the next argument.
To back up data using dd:
To restore data using dd:
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