diff --git a/man/ganeti-confd.rst b/man/ganeti-confd.rst new file mode 100644 index 0000000000000000000000000000000000000000..3370664eb0905252fd2913bc55a4e1be6f52fd34 --- /dev/null +++ b/man/ganeti-confd.rst @@ -0,0 +1,49 @@ +ganeti-confd(8) Ganeti | Version @GANETI_VERSION@ +================================================= + +Name +---- + +ganeti-confd - Ganeti conf daemon + +Synopsis +-------- + +**ganeti-confd** [-f] [-d] + +DESCRIPTION +----------- + +**ganeti-confd** is a daemon used to answer queries related to the +configuration of a Ganeti cluster. + +For testing purposes, you can give the ``-f`` option and the +program won't detach from the running terminal. + +Debug-level message can be activated by giving the ``-d`` option. + +ROLE +~~~~ + +The role of the conf daemon is to make sure we have a highly available +and very fast way to query cluster configuration values. This daemon +is automatically active on all master candidates, and so has no single +point of failure. It communicates via UDP so each query can easily be +sent to multiple servers, and it answers queries from a cached copy of +the config it keeps in memory, so no disk access is required to get an +answer. + +The config is reloaded from disk automatically when it changes, with a +rate limit of once per second. + +If the conf daemon is stopped on all nodes, its clients won't be able +to get query answers. + +COMMUNICATION PROTOCOL +~~~~~~~~~~~~~~~~~~~~~~ + +The confd protocol is an HMAC authenticated json-encoded custom +format, over UDP. A client library is provided to make it easy to +write software to query confd. More information can be found in the +Ganeti 2.1 design doc, and an example usage can be seen in the +(external) NBMA daemon for Ganeti.