FreeBSD is a UNIX-like operating system based on the “4.4BSD-Lite” released by the University of California at Berkeley with some “4.4BSD-Lite2” enhancements for i386, amd64, IA-64, arm, MIPS, PowerPC, ppc64, PC -98, UltraSPARC, and other platforms.
FreeBSD includes a number of other great features:
- Firewalls: The base system includes IPFW and IPFilter, as well as a modified version of the popular pf with improved SMP performance. IPFW also includes the dummynet feature, allowing network administrators to simulate adverse network conditions, including latency, jitter, packet loss and limited bandwidth.
- Jails are a light-weight alternative to virtualization. Allowing processes to be restricted to a namespace with access only to the file systems and network addresses assigned to that namespace. Jails are also Hierarchical, allowing jails-within-jails.
- Linux emulation provides a system call translation layer that allows unmodified Linux binaries to be run on FreeBSD systems.
- DTrace provides a comprehensive framework for tracing and troubleshooting kernel and application performance issues while under live load.
- The Ports Collection is a set of more than 23,000 third party applications that can be easily installed and run on FreeBSD. The ports architecture also allows for easy customization of the compile time options of many of the applications.
- Network Virtualization: A container (“vimage”) has been implemented, extending the FreeBSD kernel to maintain multiple independent instances of networking state. Vimage facilities can be used independently to create fully virtualized network topologies, and jail(8) can directly take advantage of a fully virtualized network stack.
FreeBSD 12.1 was released.