[pgpool-general: 8493] received degenerate backend request for node_id: 0 from pid [$pid]

[Giuseppe Sacco]

Hello,
we are still investigating about a problem in which pgpool sets our master as
down while it seems to be working fine.
Browsing all the logs about the time of the problem, we found those lines:


[unknown] pid 3166920: LOG:  received degenerate backend request for node_id: 0 from pid [3166920]
[unknown] pid 3166920: LOG:  signal_user1_to_parent_with_reason(0)
main pid 1486879: LOG:  Pgpool-II parent process received SIGUSR1
main pid 1486879: LOG:  Pgpool-II parent process has received failover request
main pid 1486879: LOG:  starting degeneration. shutdown host <IP redacted>(5995)
main pid 1486879: LOG:  Restart all children
main pid 1486879: LOG:  find_primary_node_repeatedly: waiting for finding a primary node
main pid 1486879: LOG:  failover: set new primary node: 0
main pid 1486879: LOG:  failover: set new main node: 1
failover done. shutdown host <IP redacted>(5995)

What does these lines means? What does it means "received degenerate backend
request"?

Thank you,
Giuseppe