Polaris - guiding the traffic home.

An extendable high availability solution for the data center and beyond, Global Server Load Balancing(GSLB), DNS-based traffic manager.

• Built as an enhancement for PowerDNS Authoritative Server.
• Load-balancing methods:
  • Weighted round-robin.
  • Topology(direct clients to end-points in the same region/datacenter).
  • Failover group(active-backup).
• Parameterized(timeout, interval, retries etc.) health monitors:
  • TCP
    • Connect to a specific port number.
    • Send string.
    • Match regular expression in response.
  • HTTP/S
    • Port number to use.
    • SSL.
    • Request a specific URL path.
    • Expect a response code from a configurable array.
  • Forced
    • Force a member to be up or down, disables health checking.
• Ability to run health checks against an IP that is different from the member IP.
• Up to 1024 addresses returned in a response.
• Different ways to handle the "all-pool-members-down" situation(fallback):
  • Return any configured end-points(ignore the health status).
  • Refuse query.
• Automatic SOA serial.
• A single Health Tracker can serve multiple DNS resolvers running on different machines.
• LB configuration validation on start-up operations.
• Elastic threads pool serving health checks.
• Asynchronous, non-blocking comms between the internal components.

See the WIKI for installation, configuration and other information.