Software-Distribution

• minimal effort for software installation and updates
• unification and thus prevention of errors
• quick reaction when rolling out security patches

Our solution

We have developed a lean and very effective software distribution for Linux which is currently being used in an installation with more than 10,000 clients and 80 servers. It has the folloing properties:

• All clients are integrated into a tree structure, a central server constituing the root SD-server. It is hosting the central software repository and the configuration, which decides which software shall be installed on which client.
• Each client downloads from its parent server the software repository and the configuration using a pull technology. The servers does not need to keep a list of its clients.
• The software distribution is running over an arbitrary number of tree levels. Each client can be a distribution server (staging server) for further clients.
• The whole system is working based on a comparison of variance comparison. Before each action the current state of the client is compared with its proposed state. Each difference is balanced. This scheme is used both while synchronizing the software repository from the server and while installing, updating or removing software. Our software distribution is therefore very immune against error situations or abortions.
• Each client can be moved or reconfigured without a new installation being necessary.
• Only open source software is being used. There are no license costs!
• A highly bandwidth optimized scheme is used for the data distribution. It can easily resume an aborted transmission without having to retransmit data.
• A feedback to the central SD-server is used to monitor the state of all systems.

• simple, lean, reliable
• perfect Linux integration
• saves bandwidth
• safety via fail-over
• no license costs!