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Feilsøking av PostgreSQL-clusteren

Info

Hele prosedyren må utføres som root. For å heve privilegiene dine til root kan du bruke kommandoen su -.

Adadvarsel

For å følge denne prosedyren må du ha utført de ytterligere konfigurasjonene for patronictl.

Tilkoblingsfeil mot databasen i PostgreSQL-clusteren til CyberElements Bastion kan ha ulike årsaker. Denne delen presenterer en generell feilsøkingsmetode som du må tilpasse til ditt tilfelle.

Kontrollere statusen til clusteren

Info

Ved å kontrollere statusen til clusteren kan du raskt finne noden eller nodene som svikter.

Du kan kontrollere statusen til clusteren med følgende kommando, som må kjøres på hver node i PostgreSQL-clusteren:

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patronictl -c /etc/patroni/config.yml topology
Eksempel på utdata på en plattform som fungerer 

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+ Cluster: 15-cleanroomvault5 ------+---------+---------+----+-----------+
| Member           | Host           | Role    | State   | TL | Lag in MB |
+------------------+----------------+---------+---------+----+-----------+
| PSQL_3           | psql_3         | Leader  | running | 2  |           |
| + PSQL_1         | psql_1         | Replica | running | 2  |         0 |
| + PSQL_2         | psql_2         | Replica | running | 2  |         0 |
+------------------+----------------+---------+---------+----+-----------+
I utdataene ovenfor tyder alt på at PostgreSQL-clusteren fungerer: lag-verdien er 0 MB for alle Replica-nodene, og alle nodene står i listen med statusen running. Du må få disse utdataene på alle nodene for å bekrefte at patroni og etcd fungerer.

Eksempel på utdata når det er et kommunikasjonsproblem mellom nodene 

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+ Cluster: 15-cleanroomvault5 ------+---------+---------+----+-----------+
| Member           | Host           | Role    | State   | TL | Lag in MB |
+------------------+----------------+---------+---------+----+-----------+
| PSQL_3           | psql_3         | Leader  | running | 2  |           |
| + PSQL_1         | psql_1         | Replica | running | 2  |       230 |
| + PSQL_2         | psql_2         | Replica | running | 2  |         0 |
+------------------+----------------+---------+---------+----+-----------+
I utdataene ovenfor er lag-verdien på 230 MB unormal: den kan tyde på et kommunikasjonsproblem mellom node 3 og node 1.
Hvis problemet vedvarer etter flere timer, er det bekreftet.

Eksempel på utdata når en node ikke er riktig startet eller stoppet 

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+ Cluster: 15-cleanroomvault5 ------+---------+---------+----+-----------+
| Member           | Host           | Role    | State   | TL | Lag in MB |
+------------------+----------------+---------+---------+----+-----------+
| PSQL_3           | psql_3         | Leader  | running | 2  |           |
| + PSQL_1         | psql_1         | Replica | started | 2  |   unknown |
| + PSQL_2         | psql_2         | Replica | stopped | 2  |   unknown |
+------------------+----------------+---------+---------+----+-----------+
I utdataene ovenfor viser tilstanden (kolonnen State) at node 1 starter. Hvis statusen started vedvarer i flere minutter, eller til og med timer, kan det være et problem med patroni eller etcd på den noden.
Node 2 er i tilstanden stopped: den er stoppet. Når en node i clusteren svikter, vises denne informasjonen bare midlertidig, før noden fjernes fra listen.

Eksempel på utdata når etcd svikter på den gjeldende noden 

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2026-04-09 16:21:39,482 - WARNING - Retrying (Retry(total=1, connect=None, read=None, redirect=0, status=None)) after connection broken by 'NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7fcaa1618390>: Failed to establish a new connection: [Errno 111] Connection refused')': /version
2026-04-09 16:21:39,482 - WARNING - Retrying (Retry(total=0, connect=None, read=None, redirect=0, status=None)) after connection broken by 'NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7fcaa1618c10>: Failed to establish a new connection: [Errno 111] Connection refused')': /version
2026-04-09 16:21:39,483 - ERROR - Failed to get list of machines from https://PSQL_3:2379/v2: MaxRetryError("HTTPSConnectionPool(host='psql_3', port=2379): Max retries exceeded with url: /version (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7fcaa1619490>: Failed to establish a new connection: [Errno 111] Connection refused'))")
Utdataene ovenfor viser en tilkoblingsfeil mot etcd, som hindrer at statusen til PostgreSQL-clusteren kan hentes.

Kontrollere statusen til tjenestene

Når noden som svikter, er identifisert, må du identifisere tjenesten som ikke fungerer. De to hovedtjenestene som brukes i PostgreSQL-clusteren, er patroni og etcd.

Info

patroni-tjenesten er avhengig av etcd-tjenesten: hvis etcd ikke fungerer, vil heller ikke patroni fungere.

For å identifisere tjenesten som svikter, kan du kjøre følgende kommandoer:

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systemctl status etcd
systemctl status patroni

Disse kommandoene viser statusen til tjenesten, sammen med de 10 siste logglinjene.

Adadvarsel

En tjeneste med statusen active (running) fungerer ikke nødvendigvis: den kan kjøre samtidig som den skriver feillogger. Det er derfor viktig å lese loggene til tjenesten for å forstå den faktiske tilstanden.

Eksempel på utdata for etcd når tjenesten fungerer 
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● etcd.service - etcd - highly-available key value store
   Loaded: loaded (/lib/systemd/system/etcd.service; enabled; preset: enabled)
   Active: active (running) since Thu 2026-04-09 16:40:01 CEST; 21h ago
   Docs: https://etcd.io/docs
           man:etcd
Main PID: 283425 (etcd)
   Tasks: 7 (limit: 2227)
   Memory: 73.2M
       CPU: 51min 9.223s
   CGroup: /system.slice/etcd.service
           └─283425 /usr/bin/etcd

Apr 10 09:26:31 PSQL_1 etcd[283425]: store.index: compact 1624026
Apr 10 09:26:31 PSQL_1 etcd[283425]: finished scheduled compaction at 1624026 (took 325.098µs)
Apr 10 10:26:31 PSQL_1 etcd[283425]: store.index: compact 1624386
Apr 10 10:26:31 PSQL_1 etcd[283425]: finished scheduled compaction at 1624386 (took 417.797µs)
Apr 10 11:26:31 PSQL_1 etcd[283425]: store.index: compact 1624746
Apr 10 11:26:31 PSQL_1 etcd[283425]: finished scheduled compaction at 1624746 (took 1.706489ms)
Apr 10 12:26:31 PSQL_1 etcd[283425]: store.index: compact 1625106
Apr 10 12:26:31 PSQL_1 etcd[283425]: finished scheduled compaction at 1625106 (took 300.098µs)
Apr 10 13:26:31 PSQL_1 etcd[283425]: store.index: compact 1625466
Apr 10 13:26:31 PSQL_1 etcd[283425]: finished scheduled compaction at 1625466 (took 311.398µs)
Eksempel på utdata for etcd når tjenesten er i feiltilstand 

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× etcd.service - etcd - highly-available key value store
    Loaded: loaded (/lib/systemd/system/etcd.service; enabled; preset: enabled)
    Active: failed (Result: exit-code) since Fri 2026-04-10 14:15:26 CEST; 5s ago
Duration: 21h 35min 20.382s
    Docs: https://etcd.io/docs
            man:etcd
    Process: 454701 ExecStart=/usr/bin/etcd $DAEMON_ARGS (code=exited, status=1/FAILURE)
Main PID: 454701 (code=exited, status=1/FAILURE)
        CPU: 12ms

Apr 10 14:15:26 PSQL_1 etcd[454701]: [WARNING] Deprecated '--logger=capnslog' flag is set; use '--logger=zap' flag instead
Apr 10 14:15:26 PSQL_1 etcd[454701]: etcd Version: 3.4.23
Apr 10 14:15:26 PSQL_1 etcd[454701]: Git SHA: Not provided (use ./build instead of go build)
Apr 10 14:15:26 PSQL_1 etcd[454701]: Go Version: go1.19.8
Apr 10 14:15:26 PSQL_1 etcd[454701]: Go OS/Arch: linux/amd64
Apr 10 14:15:26 PSQL_1 etcd[454701]: setting maximum number of CPUs to 1, total number of available CPUs is 1
Apr 10 14:15:26 PSQL_1 etcd[454701]: error listing data dir: /var/lib/etcd/cleanroom
Apr 10 14:15:26 PSQL_1 systemd[1]: etcd.service: Main process exited, code=exited, status=1/FAILURE
Apr 10 14:15:26 PSQL_1 systemd[1]: etcd.service: Failed with result 'exit-code'.
Apr 10 14:15:26 PSQL_1 systemd[1]: Failed to start etcd.service - etcd - highly-available key value store.
I utdataene ovenfor har etcd-tjenesten statusen failed, og feilen som hindret den i å starte, er den på linje 17: tjenesten kan ikke lese innholdet i katalogen /var/lib/etcd/cleanroom. I dette tilfellet må du justere tillatelsene på katalogen.

Eksempel på utdata for patroni når tjenesten fungerer 
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● patroni.service - Runners to orchestrate a high-availability PostgreSQL
   Loaded: loaded (/lib/systemd/system/patroni.service; enabled; preset: enabled)
   Drop-In: /etc/systemd/system/patroni.service.d
           └─local.conf
   Active: active (running) since Thu 2026-04-09 16:40:06 CEST; 22h ago
   Process: 283510 ExecStartPre=/usr/bin/testetcd.py (code=exited, status=0/SUCCESS)
Main PID: 283517 (patroni)
   Tasks: 13 (limit: 2227)
   Memory: 56.1M
       CPU: 26min 54.918s
   CGroup: /system.slice/patroni.service
           ├─283517 /usr/bin/python3 /usr/bin/patroni /etc/patroni/config.yml
           ├─283537 /usr/lib/postgresql/15/bin/postgres -D /var/lib/postgresql/15/cleanroomvault5 --config-file=/etc/postgresql/15/cleanroomvault5/postgresql.conf"--listen_addresses=*" --port=5432 --cluster_name=15-cleanroomvault5 --wal_level=replica --hot_standby=on --max_connections=100 --max_wal_senders=10--max_prepared_transactions=0 --max_locks_per_transaction=64 --track_commit_timestamp=off --max_replication_slots=10 --max_worker_processes=8 --wal_log_hints=on
          ├─283538 "postgres: 15-cleanroomvault5: logger "
          ├─283540 "postgres: 15-cleanroomvault5: checkpointer "
           ├─283541 "postgres: 15-cleanroomvault5: background writer "
          ├─283542 "postgres: 15-cleanroomvault5: startup recovering 00000003000000000000000F"
          ├─283545 "postgres: 15-cleanroomvault5: walreceiver "
          └─283547 "postgres: 15-cleanroomvault5: postgres postgres [local] idle"
Apr 10 14:51:07 PSQL_1 patroni[283517]: 2026-04-10 14:51:07,381 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:51:17 PSQL_1 patroni[283517]: 2026-04-10 14:51:17,428 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:51:27 PSQL_1 patroni[283517]: 2026-04-10 14:51:27,381 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:51:37 PSQL_1 patroni[283517]: 2026-04-10 14:51:37,428 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:51:47 PSQL_1 patroni[283517]: 2026-04-10 14:51:47,381 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:51:57 PSQL_1 patroni[283517]: 2026-04-10 14:51:57,428 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:52:07 PSQL_1 patroni[283517]: 2026-04-10 14:52:07,381 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:52:17 PSQL_1 patroni[283517]: 2026-04-10 14:52:17,428 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:52:27 PSQL_1 patroni[283517]: 2026-04-10 14:52:27,381 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Apr 10 14:52:37 PSQL_1 patroni[283517]: 2026-04-10 14:52:37,474 INFO: no action. I am (PSQL_1), a secondary, and following a leader (PSQL_2)
Eksempel på utdata for patroni når tjenesten er i feiltilstand 

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● patroni.service - Runners to orchestrate a high-availability PostgreSQL
    Loaded: loaded (/lib/systemd/system/patroni.service; enabled; preset: enabled)
    Drop-In: /etc/systemd/system/patroni.service.d
            └─local.conf
    Active: active (running) since Thu 2026-04-09 16:40:06 CEST; 23h ago
    Process: 283510 ExecStartPre=/usr/bin/testetcd.py (code=exited, status=0/SUCCESS)
Main PID: 283517 (patroni)
    Tasks: 12 (limit: 2227)
    Memory: 61.7M
        CPU: 28min 8.337s
    CGroup: /system.slice/patroni.service
            ├─283517 /usr/bin/python3 /usr/bin/patroni /etc/patroni/config.yml
            ├─283537 /usr/lib/postgresql/15/bin/postgres -D /var/lib/postgresql/15/cleanroomvault5 --config-file=/etc/postgresql/15/cleanroomvault5/postgresql.conf "--listen_addresses=*" --port=5432 --cluster_name=15-cleanroomvault5 --wal_level=replica --hot_standby=on --max_connections=100 --max_wal_senders=10 --max_prepared_transactions=0 --max_locks_per_transaction=64 --track_commit_timestamp=off --max_replication_slots=10 --max_worker_processes=8 --wal_log_hints=on
            ├─283538 "postgres: 15-cleanroomvault5: logger "
            ├─283540 "postgres: 15-cleanroomvault5: checkpointer "
            ├─283541 "postgres: 15-cleanroomvault5: background writer "
            ├─283542 "postgres: 15-cleanroomvault5: startup recovering 00000003000000000000000F"
            └─283547 "postgres: 15-cleanroomvault5: postgres postgres [local] idle"

Apr 10 15:52:37 PSQL_1 patroni[283517]: 2026-04-10 15:52:37,680 WARNING: Loop time exceeded, rescheduling immediately.
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:37,681 INFO: Lock owner: PSQL_2; I am PSQL_1
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,069 ERROR: Request to server https://PSQL_3:2379 failed: ReadTimeoutError("HTTPSConnectionPool(host='psql_3', port=2379): Read timed out. (read timeout=3.3331721344341836)")
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,069 INFO: Reconnection allowed, looking for another server.
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,069 INFO: Retrying on https://PSQL_1:2379
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,073 ERROR: Request to server https://PSQL_1:2379 failed: MaxRetryError("HTTPSConnectionPool(host='psql_1', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7fd77c411090>: Failed to establish a new connection: [Errno 111] Connection refused'))")
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,073 INFO: Reconnection allowed, looking for another server.
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,073 INFO: Retrying on https://PSQL_2:2379
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,074 ERROR: Request to server https://PSQL_2:2379 failed: MaxRetryError("HTTPSConnectionPool(host='psql_2', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7fd77c411090>: Failed to establish a new connection: [Errno 111] Connection refused'))")
Apr 10 15:52:41 PSQL_1 patroni[283517]: 2026-04-10 15:52:41,074 INFO: Reconnection allowed, looking for another server.
I tilfellet ovenfor har tjenesten statusen active (running) uten at den faktisk fungerer: loggene viser ulike tilkoblingsfeil mot etcd, som patroni trenger.
I dette eksemplet er det ikke nødvendigvis patroni som er årsaken: siden den er avhengig av etcd, må du først rette etcd-problemene og deretter kontrollere statusen til patroni på nytt.

Feilsøkingsprosedyrer for tjenestene

Nedenfor finner du én feilsøkingsprosedyre per tjeneste. Hvis både etcd og patroni svikter, begynner du med etcd.