Obsolete:Loreley

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Loreley is an HTTP reverse-proxy written by river. it runs on diderot to load-balance search requests.

The config is in /opt/loreley/etc/loreley.conf. To reload the config you must KILL AND RESTART the running loreley: it will NOT honour HUP requests to rehash (this will be implemented in the future).

to start it, log in to diderot, screen -r, switch to screen #0 and run "src/loreley/loreley -f" (this is temporary while it's in testing).

The config consists of a series of three objects:

  • groups
  • listeners
  • backends

A backend is a backend server, e.g. an apache or a search server. All backends belong to exactly one group, either "<default>" or the group given to them in the config.

A "listener" is a listening socket that accepts client requests. All listeners also belong to exactly one group, as with backends. A listener only sends requests to backends in the same group as it. In this way requests to a particular IP / port can be routed to a particular backend group.

There is also a failover backend group which can be used when a listener finds that all of its backends are down…we don't use this.