UCARP is a software that enables multiple hosts to utilize shared virtual IP addresses, ensuring automatic failover.
The CARP protocol offers several advantages, including low overhead, cryptographically signed messages, interoperability between various operating systems, and no requirement for any dedicated, extra network link between redundant hosts.
Installing UCARP is straightforward, as the `configure' shell script automatically guesses the correct values for various system-dependent variables used during compilation. The script can also create one or more `.h' files containing system-dependent definitions and a `config.status' shell script that can be used to recreate the current configuration. If needed, users can enable caching to speed up reconfiguring.
To compile UCARP, users only need to `cd' to the directory containing the package's source code, type `./configure' to configure the package for their system, followed by `make' to compile the package, and `make install' to install the programs, data files, and documentation. Extra functionalities, such as self-tests, can be run using the `make check' command.
To use UCARP, a couple of virtual hosts must be given a shared virtual IP, a real IP address for each host, a shared identifier for the virtual IP address, an advertisement time base and skew for each host (which is the frequency the host will tell the other one it's still alive), and a shared password (that remains encrypted throughout communication). Users also need a script to bring the virtual address up when a host becomes the master and another script to bring the virtual address down when a host is no longer the master.
UCARP's light protocol ensures that a tiny packet every second won't have any noticeable impact on users' network, making it an ideal tool for services that require high availability.
Version 1.5.1: N/A