[pgpool-committers: 785] pgpool: Avoid split-brain situation reported in [pgpool-general: 1046]

[Yugo Nagata]

Avoid split-brain situation reported in [pgpool-general: 1046]

After all backend nodes are detached from pgpools and then some backend node
are attached to these, multiple active pgpools could exist simultaneously,
that is to say, split-brain situation occurs.

In this fix, when once all backend DB nodes are detached from pgpool, the pgpool
stays DOWN status until this is restarted. The pgpool in DOWN status cannot
escalate to active (delegate IP holder), so split-brain situation is avoided.

[pgpool-general: 1046]
watchdog enabled delegate_IP on multiple nodes simultaneously
http://www.sraoss.jp/pipermail/pgpool-general/2012-September/001064.html

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=90a07a276440dd6ab2ab6d2030af70ac23e90b98

Modified Files
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watchdog/wd_lifecheck.c |   24 ++++++++----------------
1 files changed, 8 insertions(+), 16 deletions(-)