BackupPC is a

free Free may refer to: Concept * Freedom, the ability to act or change without constraint or restriction * Emancipate, attaining civil and political rights or equality * Free (''gratis''), free of charge * Gratis versus libre, the difference betw ...

disk-to-disk

backup software In information technology, a backup, or data backup is a copy of computer data taken and stored elsewhere so that it may be used to restore the original after a data loss event. The verb form, referring to the process of doing so, is " back up ...

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

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

Solaris Solaris is the Latin word for sun. It may refer to: Arts and entertainment Literature, television and film * ''Solaris'' (novel), a 1961 science fiction novel by Stanisław Lem ** ''Solaris'' (1968 film), directed by Boris Nirenburg ** ''Sol ...

, or

UNIX Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user 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 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 used to share files, printers, serial ports, and miscellaneous communications between nodes on a network. On Microsoft Windows, the SMB implementation consists of two vaguely named Windows ...

(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 Protocol) 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 was designed for ...

(SSH) with

GNU tar In computing, tar is a shell command for combining multiple computer files into a single archive file. It was originally developed for magnetic tape storage reading and writing data for a sequential I/O device with no file system, and the ...

and

rsync rsync (remote sync) is a utility for 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 opera ...

available, as it allows the BackupPC server to be stored in a subnet separate from the web server's

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. It is published under the

GNU General Public License The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first ...

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 free and open-source Unix-like environment and command-line interface (CLI) for Microsoft Windows. The project also provides a software repository containing open-source packages. Cygwin allows source code for Unix-like operati ...

) 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 An IT administrator, system administrator, 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 Server (computing), servers. The ...

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