Salt Project

Salt Project is an open source configuration management and remote execution tool for self-hosted server fleets, maintained by Broadcom under Apache 2.0.

Salt Project keeps large numbers of servers in a known state and runs commands across thousands of them from a single control plane. Its full-time core maintainers are employed by Broadcom, in the VMware by Broadcom Tanzu division. SaltStack, the original sponsor, was acquired by VMware, and the same engine now powers Broadcom's commercial VMware Tanzu Salt. A Salt master sends work to minions, the agents installed on each managed host. Salt states, written as SLS files, declare the end state of a system, and requisites set the order between them. Grains describe each machine, and pillar holds the data a state needs, including secrets that the renderer decrypts with GPG. A state applied to a host that already matches reports no changes, and a test run lists what would change without touching anything. Salt SSH reaches hosts with no minion through a roster file, while Reactor maps events, including those raised by beacons, to automatic responses. Salt suits operations and platform teams that run many Linux and Windows servers and want the automation engine on their own infrastructure. Network engineers working with Juniper, Cisco or Arista equipment can manage those devices with the same states. Access on the master is granted per user or group through external authentication backed by PAM or LDAP, which fits organizations already running a directory. The open source edition is self-hosted, and its users help each other on Discord and GitHub. Broadcom also sells VMware Tanzu Salt, a commercial edition built on the same engine. Teams reach for Salt when one configuration change has to land on a large fleet at once. A minion schedule can re-run the highstate on an interval, pulling drifted machines back into line without anyone logging in. Salt Cloud provisions virtual machines on Amazon EC2, Google Compute Engine and Azure. Network teams push switch and router configuration through NAPALM, and Windows administrators install software from winrepo. With remote execution, configuration management and infrastructure orchestration in one engine, a mixed estate of servers, cloud instances and network devices answers to a single set of states.