Tag: crontab

About

The crontab command, found in Unix and Unix-like operating systems, is used to schedule commands to be executed periodically. It reads a series of commands from standard input and collects them into a file also known as a "crontab" which is later read and whose instructions are carried out. The name is derived from Greek chronos (χρόνος), meaning time.

Generally, the schedules modified by crontab are enacted by a daemon, crond, which runs constantly in the background and checks once a minute to see if any of the scheduled jobs need to be executed. If so, it executes them. These jobs are generally referred to as cron jobs.

From en.wikipedia.org/wiki/Crontab

Tag: SSH key

About

A randomly generated sequence of bytes, that machines use to identify eachother with over SSH. See it as a fingerprint.

Tag: ubuntu

About

Ubuntu (IPA pronunciation /ùbúntú/) is a predominantly desktop-oriented Linux distribution, based on Debian GNU/Linux but with a stronger focus on usability, regular releases, and ease of installation. Ubuntu is sponsored by Canonical Ltd, owned by South African Mark Shuttleworth; the name of the distribution comes from the African concept of ubuntu which may be rendered roughly as "humanity toward others", though other meanings have been suggested.

The most recent version, Ubuntu 7.04 (Feisty Fawn), was released on April 19, 2007. Version 7.10 (Gutsy Gibbon) is scheduled for release on October 18, 2007. Ubuntu aims to use only free software to provide an up-to-date yet stable operating system for the average user.

Kubuntu and Xubuntu are official subprojects of the Ubuntu project, aiming to bring the KDE and Xfce desktop environments to the Ubuntu core, respectively. Edubuntu is an official subproject "designed for school environments, and should be equally suitable for kids to use at home."

From en.wikipedia.org/wiki/Ubuntu_(Linux_distribution)

Tag: linux

About

Linux (IPA pronunciation: /ˈlɪnʊks/) is a Unix-like computer operating system. Linux is one of the most prominent examples of free software and open source development; its underlying source code can be freely modified, used, and redistributed by anyone.

The Linux kernel was first released to the public on 17 September 1991, for the Intel x86 PC architecture. The kernel was augmented with system utilities and libraries from the GNU project to create a usable operating system, which later led to the alternate term GNU/Linux. Linux is now packaged for different uses in Linux distributions, which contain the sometimes modified kernel along with a variety of other software packages tailored to different requirements.

Predominantly known for its use in servers, Linux has gained the support of corporations such as IBM, Sun Microsystems, Dell, Hewlett-Packard, and Novell, and is used as an operating system for a wide variety of computer hardware, including desktop computers, supercomputers, and embedded devices such as mobile phones and routers.

From en.wikipedia.org/wiki/Linux

Tag: rsync

About

In computing, rsync is a computer program for Unix systems which synchronizes files and directories from one location to another while minimizing data transfer using delta encoding when appropriate. An important feature of rsync not found in most similar programs/protocols is that the mirroring takes place with only one transmission in each direction. rsync can copy or display directory contents and copy files, optionally using compression and recursion.

rsyncd, the rsync protocol daemon, uses the default TCP port of 873. rsync can also be used to synchronize local directories, or via a remote shell such as RSH or SSH. In the latter case, the rsync client executable must be installed on both the local and the remote host.

Released under the GNU General Public License, rsync is free software.

From en.wikipedia.org/wiki/Rsync

Synchronize files with rsync

Synchronizing files from one server to another is quite awesome. You can use it for backups, for keeping web servers in sync, and much more. It's fast and it doesn't take up as much bandwidth as normal copying would. And the best thing is, it can be done with only 1 command. Welcome to the wonderful world of rsync.

Tag: backup

About

In information technology, backup refers to making copies of data so that these additional copies may be used to restore the original after a data loss event. These additional copies are typically called "backups." Backups are useful primarily for two purposes: 1) to restore a computer to an operational state following a disaster (called disaster recovery) and 2) to restore small numbers of files after they have been accidentally deleted or corrupted.

Due to a considerable overlap in technology, backups and backup systems are frequently confused with archives and fault-tolerant systems. Backups differ from archives in the sense that archives are the primary copy of data and backups are a secondary copy of data. Backup systems differ from fault-tolerant systems in the sense that backup systems assume that a fault will cause a data loss event and fault-tolerant systems assume a fault will not. Backups are typically that last line of defense against data loss, and consequently the least granular and the least convenient to use.

Since a backup system contains at least one copy of all data worth saving, the data storage requirements are considerable. Organizing this storage space and managing the backup process is a complicated undertaking.

From en.wikipedia.org/wiki/Backup

Tag:synchronization

About

In computer science, synchronization refers to one of two distinct, but related concepts: synchronization of processes, and synchronization of data. Process synchronization refers to the idea that multiple processes are to join up or handshake at a certain point, so as to reach an agreement or commit to a certain sequence of action. Data synchronization refers to the idea of keeping multiple copies of a dataset in coherence with one another, or to maintain data integrity. Process synchronization primitives are commonly used to implement data synchronization.

Synchronize files with rsync

Synchronizing files from one server to another is quite awesome. You can use it for backups, for keeping web servers in sync, and much more. It's fast and it doesn't take up as much bandwidth as normal copying would. And the best thing is, it can be done with only 1 command. Welcome to the wonderful world of rsync.