Docs/SysAdmin/Server/Webmin
From Mandriva Community Wiki
- a web-based administration tool
Webmin is a web-based interface that contains multiple modules to assist the administrator to configure and maintain multiple utilities and perform tasks with a comfortable GUI interface. Using pre-configured modules is more limiting than performing the tasks by hand but for administrators that are seeking to do routine maintenance, the interface can help protect against common mistakes and enable maintenance within standard guidelines.
Another advantage within the Webmin interface is that Webmin can be configured to access multiple machines that are linked (called clusters) and perform common tasks on all of the machines at the same time. This includes common functions like installing new software, maintaining access control lists, syncing users and groups across multiple machines, etc. The advantage here is that changes made to one machine are automatically pushed out to the other linked machines with minimal intervention by the administrator. This simplifies the task of maintaining multiple machines that are all running the same software and require similar configurations.
Setting up this requires that webmin be installed on all of the machines that are to be clustered together. Once the software resides on each machine, webmin needs to be configured to see each of the other machines that it will administer. You can do this by opening up the main webmin interface and clicking on the Webmin Servers Index panel under the Webmin tab. You can either browse the network for all webmin servers and add them, or you can manually add the servers and configure the main login on each machine. This does create a possible security issue since if access is obtained to the main administration machine, then access would also be available on the other machines but if users and groups are replicated across all of the machines, most likely access would follow each in turn anyway.
Once the servers have been configured, you can go to the Cluster tab on the Webmin panel. Here you can define Cron jobs that are shared across machines, and install software packages across all machines using the Cluster Software Packages panel. You can also configure a cluster of Webmin servers which allows you to synchronize webmin users and groups across the machines, as well as upgrade webmin software on all machines in the cluster.
The Cluster options on Webmin are technically meant to help administrators maintain multiple servers set up identically to each other in clusters for load balancing and performance reasons. However, there are still advantages to be gained in multiple machine environments even when this is not the case as long as specific things need to be maintained identically on the computers.
