If repmgrd is monitoring a primary which is taken off-line, then later
restored as a standby, detect this change and resume monitoring
in standby node.
Addresses GitHub #338.
All disconnected nodes will be in a static, known state, so as long as
each node has the same meta-information (repmgr.nodes) and is able
to retrieve the last receive LSN of the other nodes, it is possible
for each node to independently determine the best promotion candidate,
thereby reaching consensus without an explicit "voting" process.
get_new_primary() returns NULL if no notification for the new primary has
been received, but the code was expecting it to return UNKNOWN_NODE_ID,
which was causing repmgrd to prematurely drop out of the new primary
detection loop if no notification had been received by the time the loop
started.
Also store the electoral term as a single row, single column table,
to ensure that all repmgrds see the same turn. It is then bumped
by the winning node after it gets promoted.
Various logging improvements.
The standby may not always be available for connections right after it's
restarted, so attempting to connect and get the node's upstream record
after the restart may fail. Record is now retrieved before the restart.
Addresses GitHub #333.
The configuration file path is stored to make remote execution of repmgr
(e.g. during "repmgr standby switchover") simpler, so relative paths
make no sense.
Addresses GitHub #332
Main body of documentation moved to DocBook format and hosted at:
https://repmgr.org/docs/index.html
as the existing README and sundry additional files were becoming
unmanageable. Conversion to DocBook format enables all documentation
to be managed in a single structured system, with cross-references,
indexes, linkable URLS etc.
