UCARP and High Availability

If you have ever played with BSD you probably ran into CARP. It allows you to build a high available service which is provided by two physical servers behind a virtual shared IP address. The CARP nodes define a master and a backup system. A master serves the content and if the master crashes, the backup system takes over automatically the virtual IP (VIP) and the client won’t notice.

Disclaimer: You should be aware this setup will not share load and increase your network throughput. It just used to increase availabilty and room to do maintenance without bringing your service down.

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