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# Sourced by managed-container; uses the shared OCF and parameter environment.
pg_command()
{
local command="$1"
mc_runtime_exec \
--user "${PG_OS_USER}" \
"${CONTAINER_NAME}" \
sh -c "${command}"
}
pgdata_path()
{
pg_command '
if [ -z "$PGDATA" ]; then
exit 1
fi
printf "%s\n" "$PGDATA"
'
}
pg_running()
{
pg_command '
BINDIR="$(pg_config --bindir)" || exit 1
"$BINDIR/pg_ctl" status -D "$PGDATA" >/dev/null 2>&1
'
}
pg_ready()
{
mc_runtime_exec \
--user "${PG_OS_USER}" \
"${CONTAINER_NAME}" \
pg_isready -q \
-U "${DB_USER}" \
-d "${DB_NAME}"
}
pg_role()
{
mc_runtime_exec \
--user "${PG_OS_USER}" \
"${CONTAINER_NAME}" \
psql \
-U "${DB_USER}" \
-d "${DB_NAME}" \
-Atqc 'SELECT pg_is_in_recovery();'
}
pg_wal_receiver_status()
{
mc_runtime_exec \
--user "${PG_OS_USER}" \
"${CONTAINER_NAME}" \
psql \
-U "${DB_USER}" \
-d "${DB_NAME}" \
-Atqc "SELECT status FROM pg_stat_wal_receiver LIMIT 1;"
}
pg_streaming()
{
[ "$(pg_wal_receiver_status 2>/dev/null || true)" = "streaming" ]
}
pg_wal_receiver_sender()
{
mc_runtime_exec \
--user "${PG_OS_USER}" \
"${CONTAINER_NAME}" \
psql \
-U "${DB_USER}" \
-d "${DB_NAME}" \
-Atqc "
SELECT sender_host || '|' || sender_port
FROM pg_stat_wal_receiver
WHERE status = 'streaming'
LIMIT 1;
"
}
mc_pg_rejoin_running_standby()
{
local primary_info primary_rc primary_node primary_host primary_port
[ -n "${OCF_RESKEY_replication_peers:-}" ] || return 1
primary_info="$(mc_pg_find_remote_primary 2>/dev/null)"
primary_rc=$?
case "${primary_rc}" in
0)
primary_node="${primary_info%%|*}"
primary_info="${primary_info#*|}"
primary_host="${primary_info%%|*}"
primary_port="${primary_info#*|}"
ocf_log warn \
"Standby is not streaming while remote primary ${primary_node} (${primary_host}:${primary_port}) is available; forcing managed rejoin"
if pg_running; then
if ! pg_command '
BINDIR="$(pg_config --bindir)" || exit 1
exec "$BINDIR/pg_ctl" \
-D "$PGDATA" \
stop -m fast -w
'
then
ocf_exit_reason \
"Unable to stop non-streaming standby before managed rejoin"
return "${OCF_ERR_GENERIC}"
fi
fi
mc_pg_require_replication_slot || return "$?"
REJOIN_SOURCE_HOST="${primary_host}"
REJOIN_SOURCE_PORT="${primary_port}"
OCF_RESKEY_rejoin_source_host="${primary_host}"
OCF_RESKEY_rejoin_source_port="${primary_port}"
if ! managed_rejoin; then
ocf_exit_reason \
"Managed rejoin of non-streaming standby against ${primary_node} failed"
return "${OCF_ERR_GENERIC}"
fi
pg_clear_rejoin_pending >/dev/null 2>&1 || true
return "${OCF_SUCCESS}"
;;
1)
# No writable peer exists. This is a normal failover-election
# condition; leave the standby running Unpromoted and let the
# promotion scorer decide whether it is eligible.
return 1
;;
2)
ocf_exit_reason \
"Multiple writable PostgreSQL peers detected while repairing non-streaming standby"
return "${OCF_ERR_GENERIC}"
;;
*)
ocf_exit_reason \
"Unable to determine PostgreSQL peer-primary state while repairing non-streaming standby"
return "${OCF_ERR_GENERIC}"
;;
esac
}
pg_rejoin_pending()
{
pg_command 'test -f "$PGDATA/.loxthelion-ha-rejoin-required"'
}
pg_mark_rejoin_pending()
{
pg_command '
umask 077
: > "$PGDATA/.loxthelion-ha-rejoin-required"
chmod 600 "$PGDATA/.loxthelion-ha-rejoin-required"
'
}
pg_clear_rejoin_pending()
{
pg_command 'rm -f "$PGDATA/.loxthelion-ha-rejoin-required"'
}
mc_pg_reconcile_rejoin_marker()
{
local primary_info primary_rc primary_node primary_host primary_port
local receiver_sender
[ -n "${OCF_RESKEY_replication_peers:-}" ] || return 1
primary_info="$(mc_pg_find_remote_primary 2>/dev/null)"
primary_rc=$?
[ "${primary_rc}" -eq 0 ] || return 1
primary_node="${primary_info%%|*}"
primary_info="${primary_info#*|}"
primary_host="${primary_info%%|*}"
primary_port="${primary_info#*|}"
receiver_sender="$(pg_wal_receiver_sender 2>/dev/null || true)"
if ! pg_streaming; then
return 1
fi
if [ "${receiver_sender}" != "${primary_host}|${primary_port}" ]; then
return 1
fi
if ! pg_clear_rejoin_pending; then
ocf_log warn \
"Standby is streaming from elected primary ${primary_node}, but rejoin-required marker could not be cleared"
return 1
fi
ocf_log info \
"Standby is verified streaming from elected primary ${primary_node} (${primary_host}:${primary_port}); cleared provisional rejoin marker"
return 0
}
pg_has_standby_signal()
{
pg_command 'test -f "$PGDATA/standby.signal"'
}
managed_monitor()
{
local role
if ! service_running; then
ocf_log debug "User service ${SERVICE_NAME} is not active"
return "${OCF_NOT_RUNNING}"
fi
if ! container_running; then
ocf_log warn \
"Service ${SERVICE_NAME} is active but container ${CONTAINER_NAME} is not running"
return "${OCF_NOT_RUNNING}"
fi
if ! pg_running; then
ocf_log debug \
"Container ${CONTAINER_NAME} is running but PostgreSQL is stopped"
return "${OCF_NOT_RUNNING}"
fi
if ! pg_ready; then
ocf_exit_reason \
"PostgreSQL process exists but pg_isready failed"
return "${OCF_ERR_GENERIC}"
fi
role="$(pg_role 2>/dev/null)" || {
ocf_exit_reason \
"PostgreSQL is accepting connections but role query failed"
return "${OCF_ERR_GENERIC}"
}
case "${role}" in
f)
ocf_log debug \
"PostgreSQL healthy: role=primary (promoted)"
return "${OCF_RUNNING_PROMOTED}"
;;
t)
# A former primary may be started provisionally in recovery when
# no writable peer exists yet, solely so Pacemaker can decide
# which Unpromoted instance to promote. Once another node becomes
# primary, force recovery of this provisional instance through a
# stop/start cycle so start() can pg_rewind it against the winner.
if pg_rejoin_pending && [ -n "${OCF_RESKEY_replication_peers:-}" ]; then
local primary_info primary_rc
primary_info="$(mc_pg_find_remote_primary 2>/dev/null)"
primary_rc=$?
case "${primary_rc}" in
0)
ocf_exit_reason \
"A remote primary is now available (${primary_info%%|*}); provisional former-primary standby requires rejoin"
return "${OCF_ERR_GENERIC}"
;;
2)
ocf_exit_reason \
"Multiple writable PostgreSQL peers detected while monitoring provisional standby"
return "${OCF_ERR_GENERIC}"
;;
esac
fi
if pg_streaming; then
ocf_log debug \
"PostgreSQL healthy: role=standby (unpromoted), WAL receiver=streaming"
return "${OCF_SUCCESS}"
fi
# A standby can legitimately lose its receiver while the cluster
# has no writable primary (for example during failover election).
# Do not declare that condition unhealthy: promotion eligibility
# is decided separately by the promotion-scoring evidence. If a
# writable primary already exists, however, a non-streaming
# standby is broken and must be repaired rather than reported OK.
if [ -n "${OCF_RESKEY_replication_peers:-}" ]; then
local primary_info primary_rc
primary_info="$(mc_pg_find_remote_primary 2>/dev/null)"
primary_rc=$?
case "${primary_rc}" in
0)
ocf_exit_reason \
"PostgreSQL standby is in recovery but WAL receiver is not streaming while remote primary ${primary_info%%|*} is available"
return "${OCF_ERR_GENERIC}"
;;
1)
ocf_log debug \
"PostgreSQL standby is disconnected and no remote primary is currently identifiable; leaving promotion eligibility to Pacemaker scoring"
return "${OCF_SUCCESS}"
;;
2)
ocf_exit_reason \
"Multiple writable PostgreSQL peers detected while monitoring standby"
return "${OCF_ERR_GENERIC}"
;;
*)
ocf_exit_reason \
"Unable to determine PostgreSQL peer-primary state while monitoring standby"
return "${OCF_ERR_GENERIC}"
;;
esac
fi
# Backward-compatible behavior when native peer discovery is not
# configured: role-aware monitoring cannot prove an upstream.
ocf_log debug \
"PostgreSQL healthy: role=standby (unpromoted); native peer discovery is not configured"
return "${OCF_SUCCESS}"
;;
*)
ocf_exit_reason \
"Unexpected pg_is_in_recovery() result: '${role}'"
return "${OCF_ERR_GENERIC}"
;;
esac
}
managed_start()
{
local i monitor_rc
managed_monitor
monitor_rc=$?
case "${monitor_rc}" in
"${OCF_SUCCESS}")
ocf_log info \
"PostgreSQL resource already running unpromoted"
return "${OCF_SUCCESS}"
;;
"${OCF_RUNNING_PROMOTED}")
ocf_exit_reason \
"Refusing start: PostgreSQL is already primary; promotion must occur through promote()"
return "${OCF_ERR_GENERIC}"
;;
"${OCF_NOT_RUNNING}")
# Expected for a stopped resource. Continue.
;;
*)
# If start() is called for an already-running standby that is in
# recovery but cannot stream from an existing primary, repair it
# instead of simply returning the monitor failure. This catches a
# previous partial rejoin whose standby.signal survived restart.
if service_running && container_running && pg_running; then
local existing_role
existing_role="$(pg_role 2>/dev/null || true)"
if [ "${existing_role}" = "t" ] && ! pg_streaming; then
if mc_pg_rejoin_running_standby; then
managed_monitor
return $?
fi
fi
fi
ocf_exit_reason \
"Cannot start unhealthy PostgreSQL instance (monitor rc=${monitor_rc})"
return "${monitor_rc}"
;;
esac
ocf_log info \
"Ensuring container service ${SERVICE_NAME} is running"
if ! service_running; then
if ! mc_lifecycle_start "${SERVICE_NAME}"
then
ocf_exit_reason \
"Failed to start ${SERVICE_NAME}"
return "${OCF_ERR_GENERIC}"
fi
fi
for i in $(seq 1 20); do
container_running && break
sleep 0.5
done
if ! container_running; then
ocf_exit_reason \
"Container ${CONTAINER_NAME} did not become running"
return "${OCF_ERR_GENERIC}"
fi
if ! pg_running; then
#
# OCF promotable-resource rule:
# start() must produce an Unpromoted instance. Missing standby.signal
# therefore never authorizes a primary start. It means either:
# * a former primary can be rewound against an existing winner, or
# * no winner exists yet, in which case place this PGDATA into
# recovery and let Pacemaker decide whether to promote it.
#
if pg_rejoin_pending || ! pg_has_standby_signal; then
local primary_info primary_rc primary_node primary_host primary_port
if [ -z "${OCF_RESKEY_replication_peers:-}" ]; then
ocf_exit_reason \
"Cannot safely recover PGDATA without standby.signal: replication_peers is required for automatic primary discovery"
return "${OCF_ERR_CONFIGURED}"
fi
# At this point the maintenance container is running, so resolve
# the exact configured slot from PostgreSQL/container state before
# any rewind or recovery configuration is written.
mc_pg_require_replication_slot || return "$?"
primary_info="$(mc_pg_find_remote_primary 2>/dev/null)"
primary_rc=$?
case "${primary_rc}" in
0)
primary_node="${primary_info%%|*}"
primary_info="${primary_info#*|}"
primary_host="${primary_info%%|*}"
primary_port="${primary_info#*|}"
ocf_log info \
"Existing remote primary ${primary_node} (${primary_host}:${primary_port}) found; rejoining local PGDATA before start"
REJOIN_SOURCE_HOST="${primary_host}"
REJOIN_SOURCE_PORT="${primary_port}"
OCF_RESKEY_rejoin_source_host="${primary_host}"
OCF_RESKEY_rejoin_source_port="${primary_port}"
if ! managed_rejoin; then
ocf_exit_reason \
"Automatic rejoin against ${primary_node} failed"
return "${OCF_ERR_GENERIC}"
fi
pg_clear_rejoin_pending >/dev/null 2>&1 || true
managed_monitor
return $?
;;
1)
ocf_log info \
"No remote primary is currently identifiable; preparing local PGDATA as Unpromoted and leaving promotion exclusively to Pacemaker"
if ! mc_pg_write_peer_recovery; then
ocf_exit_reason \
"Unable to place PGDATA into native standby recovery while no primary exists"
return "${OCF_ERR_GENERIC}"
fi
if ! pg_mark_rejoin_pending; then
ocf_exit_reason \
"Unable to mark provisional standby as requiring rejoin if another node wins promotion"
return "${OCF_ERR_GENERIC}"
fi
;;
2)
ocf_exit_reason \
"Multiple writable PostgreSQL peers detected; refusing start"
return "${OCF_ERR_GENERIC}"
;;
*)
ocf_exit_reason \
"Unable to determine PostgreSQL peer-primary state"
return "${OCF_ERR_GENERIC}"
;;
esac
fi
ocf_log info \
"Starting PostgreSQL as an unpromoted standby inside ${CONTAINER_NAME}"
if ! pg_command '
BINDIR="$(pg_config --bindir)" || exit 1
exec "$BINDIR/pg_ctl" \
-D "$PGDATA" \
-l "$PGDATA/postgresql.log" \
start -w
'
then
ocf_exit_reason "pg_ctl start failed"
return "${OCF_ERR_GENERIC}"
fi
fi
managed_monitor
monitor_rc=$?
case "${monitor_rc}" in
"${OCF_SUCCESS}")
ocf_log info \
"PostgreSQL start completed in unpromoted state"
return "${OCF_SUCCESS}"
;;
"${OCF_RUNNING_PROMOTED}")
ocf_exit_reason \
"PostgreSQL became primary during start; stopping it to preserve OCF role semantics"
pg_command '
BINDIR="$(pg_config --bindir)" || exit 1
exec "$BINDIR/pg_ctl" \
-D "$PGDATA" \
stop -m fast -w
' >/dev/null 2>&1 || true
return "${OCF_ERR_GENERIC}"
;;
*)
# standby.signal can exist while the standby is still unusable
# (for example, its required WAL was removed after a failed
# primary repair). If a writable peer exists, route the instance
# through managed_rejoin(), whose guarded basebackup fallback can
# rebuild PGDATA when rewind alone cannot establish streaming.
if pg_running; then
local final_role
final_role="$(pg_role 2>/dev/null || true)"
if [ "${final_role}" = "t" ] && ! pg_streaming; then
if mc_pg_rejoin_running_standby; then
managed_monitor
return $?
fi
fi
fi
return "${monitor_rc}"
;;
esac
}
managed_stop()
{
local i
if container_running && pg_running; then
ocf_log info \
"Stopping PostgreSQL cleanly inside ${CONTAINER_NAME}"
if ! pg_command '
BINDIR="$(pg_config --bindir)" || exit 1
exec "$BINDIR/pg_ctl" \
-D "$PGDATA" \
stop -m fast -w
'
then
ocf_exit_reason "pg_ctl stop failed"
return "${OCF_ERR_GENERIC}"
fi
fi
if service_running; then
ocf_log info \
"Stopping container service ${SERVICE_NAME}"
if ! mc_lifecycle_stop "${SERVICE_NAME}"
then
ocf_exit_reason \
"Failed to stop ${SERVICE_NAME}"
return "${OCF_ERR_GENERIC}"
fi
fi
for i in $(seq 1 20); do
if ! service_running && ! container_running; then
return "${OCF_SUCCESS}"
fi
sleep 0.5
done
if service_running; then
ocf_exit_reason \
"${SERVICE_NAME} remained active after stop"
return "${OCF_ERR_GENERIC}"
fi
if container_running; then
ocf_exit_reason \
"${CONTAINER_NAME} remained running after stop"
return "${OCF_ERR_GENERIC}"
fi
return "${OCF_SUCCESS}"
}
# Conservative scoring eligibility only; this does not replace role detection,
# fencing, the promotion action, or the existing controlled-demote WAL checks.
# This strict predicate remains unchanged; disconnected policy is separate below.
mc_pg_promotion_eligible()
{
local eligible
# A provisional former primary must never become promotion-eligible.
# It may run in recovery so Pacemaker can observe it, but it must first
# complete a real rejoin/rewind against the elected primary.
if pg_rejoin_pending; then
return 1
fi
eligible="$(
mc_runtime_exec_bounded 3s --user "${PG_OS_USER}" \
--env 'PGOPTIONS=-c statement_timeout=2000' \
"${CONTAINER_NAME}" \
psql -X -v ON_ERROR_STOP=1 -U "${DB_USER}" -d "${DB_NAME}" -Atqc "
SELECT CASE WHEN pg_is_in_recovery() THEN
NOT pg_is_wal_replay_paused()
AND EXISTS (
SELECT 1 FROM pg_stat_wal_receiver
WHERE status = 'streaming'
AND flushed_lsn IS NOT NULL
AND pg_last_wal_replay_lsn() >= flushed_lsn
)
ELSE false END;
" 2>/dev/null
)" || return 1
[ "${eligible}" = t ]
}
# One observation supplies both strict connected eligibility and disconnected
# evidence. PostgreSQL restart time deliberately invalidates prior observations,
# including a new basebackup sharing the same PostgreSQL system identifier.
mc_pg_standby_observation()
{
mc_runtime_exec_bounded 3s --user "${PG_OS_USER}" \
--env 'PGOPTIONS=-c statement_timeout=2000' \
"${CONTAINER_NAME}" \
psql -X -v ON_ERROR_STOP=1 -U "${DB_USER}" -d "${DB_NAME}" -Atqc "
WITH s AS MATERIALIZED (
SELECT pg_is_in_recovery() AS recovery,
pg_last_wal_replay_lsn() AS replay,
r.status AS receiver, r.flushed_lsn AS flush
FROM (SELECT 1) AS singleton
LEFT JOIN pg_stat_wal_receiver r ON true
)
SELECT json_build_object(
'identity', json_build_array(
(SELECT system_identifier::text FROM pg_control_system()),
current_setting('data_directory'),
extract(epoch FROM pg_postmaster_start_time())::text),
'recovery', recovery,
'paused', CASE WHEN recovery THEN pg_is_wal_replay_paused() ELSE true END,
'receiver', receiver, 'replay', replay::text, 'flush', flush::text,
'strict', CASE WHEN recovery THEN
NOT pg_is_wal_replay_paused() AND receiver = 'streaming'
AND flush IS NOT NULL AND replay >= flush
ELSE false END)
FROM s;
" 2>/dev/null
}
mc_pg_standby_score()
{
local observation
# Hard promotion veto for provisional former-primary PGDATA. Returning
# -INFINITY here ensures Pacemaker cannot choose this instance while the
# rejoin-required marker exists, even though monitor may report it as a
# healthy Unpromoted standby.
if pg_rejoin_pending; then
if ! mc_pg_reconcile_rejoin_marker; then
printf '%s\n' '-INFINITY'
return 0
fi
fi
observation="$(mc_pg_standby_observation)" || return 1
# The helper is root-owned alongside the modules; state never enters the
# rootless container. A failed/slow helper always withdraws eligibility.
printf '%s' "${observation}" | timeout --kill-after=1s 1s python3 \
"${MC_APPLICATION_DIR}/promotion_state.py" \
"${MC_PROMOTION_RESOURCE_INSTANCE:-}" \
"${SERVICE_USER}" "${SERVICE_NAME}" "${CONTAINER_NAME}" \
"${OCF_RESKEY_disconnected_max_age:-300}"
}