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.
- TCP
- 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.
