BackupPC is a

free Free may refer to: Concept * Freedom, having the ability to do something, without having to obey anyone/anything * Freethought, a position that beliefs should be formed only on the basis of logic, reason, and empiricism * Emancipate, to procur ...

disk-to-disk

backup software Backup software are computer programs used to perform a backup; they create supplementary exact copies of files, databases or entire computers. These programs may later use the supplementary copies to restore the original contents in the event of ...

suite with a web-based frontend. The cross-platform server will run on any

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which i ...

, Solaris, or

UNIX Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

-based server. No client is necessary, as the server is itself a client for several protocols that are handled by other services native to the client OS. In 2007, BackupPC was mentioned as one of the three most well known open-source backup software, even though it is one of the tools that are "so amazing, but unfortunately, if no one ever talks about them, many folks never hear of them".

Data deduplication In computing, data deduplication is a technique for eliminating duplicate copies of repeating data. Successful implementation of the technique can improve storage utilization, which may in turn lower capital expenditure by reducing the overall amou ...

reduces the disk space needed to store the backups in the disk pool. It is possible to use it as

D2D2T Disk staging is using disks as an additional, temporary stage of backup process before finally storing backup to tape. Backups stay on disk typically for a day or a week, before being copied to tape in a background process and deleted afterwards. ...

solution, if the archive function of BackupPC is used to back up the disk pool to tape. BackupPC is not a block-level backup system like Ghost4Linux but performs file-based backup and restore. Thus it is not suitable for backup of disk images or raw disk partitions. BackupPC incorporates a

Server Message Block Server Message Block (SMB) is a communication protocol originally developed in 1983 by Barry A. Feigenbaum at IBM and intended to provide shared access to files and printers across nodes on a network of systems running IBM's OS/2. It also provide ...

(SMB) client that can be used to back up network shares of computers running Windows. Paradoxically, under such a setup the BackupPC server can be located behind a NAT'd firewall while the Windows machine operates over a public IP address. While this may not be advisable for SMB traffic, it is more useful for web servers running

Secure Shell The Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network. Its most notable applications are remote login and command-line execution. SSH applications are based ...

(SSH) with GNU tar and

rsync rsync is a utility for efficiently transferring and synchronizing files between a computer and a storage drive and across networked computers by comparing the modification times and sizes of files. It is commonly found on Unix-like operatin ...

available, as it allows the BackupPC server to be stored in a subnet separate from the web server's DMZ. It is published under the

GNU General Public License The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end user In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ulti ...

Protocols supported

BackupPC supports NFS, SSH, SMB and rsync. It can back up Unix-like systems with native ssh and tar or rsync support, such as Linux, BSD, and OS X, as well as Microsoft Windows shares with minimal configuration. On Windows, third party implementations of tar, rsync, and SSH (such as

Cygwin Cygwin ( ) is a POSIX-compatible programming and runtime environment that runs natively on Microsoft Windows. Under Cygwin, source code designed for Unix-like operating systems may be compiled with minimal modification and executed. The Cygwin i ...

) are required to utilize those protocols.

Protocol choice

The choice between tar and rsync is dictated by the hardware and bandwidth available to the client. Clients backed up by rsync use considerably more CPU time than client machines using tar or SMB. Clients using SMB or tar use considerably more bandwidth than clients using rsync. These trade-offs are inherent in the differences between the protocols. Using tar or SMB transfers each file in its entirety, using little CPU but maximum bandwidth. The rsync method calculates checksums for each file on both the client and server machines in a way that enables a transfer of just the differences between the two files; this uses more CPU resources, but minimizes bandwidth.

Data storage

Version 3.x

BackupPC uses a combination of hard links and compression to reduce the total disk space used for files. At the first full backup, all files are transferred to the backend, optionally compressed, and then compared. Files that are identical are hard linked, which uses only one additional directory entry. The upshot is that an astute

system administrator A system administrator, or sysadmin, or admin is a person who is responsible for the upkeep, configuration, and reliable operation of computer systems, especially multi-user computers, such as servers. The system administrator seeks to en ...

could potentially back up ten Windows XP laptops with 10 GB of data each, and if 8 GB is repeated on each machine (Office and Windows binary files) would look like 100 GB is needed, but only 28 GB (10 × 2 GB + 8 GB) would be used. Compression of the data on the back-end will further reduce that requirement. When browsing the backups, incremental backups are automatically filled back to the previous full backup. So every backup appears to be a full and complete set of data.

Version 4.x

Version 4.x can still use V3.x repositories, but all new backups use a new format (seamless upgrade). The overall performance is higher than with the V3.x version.

References

External links

* {{DEFAULTSORT:Backuppc 2001 software Free backup software Backup software for Linux Free software programmed in Perl Perl software