Powerflex Management Platform: keycloak-0-logfiler HTTP-sonden mislykkedes med statuskode: 503

Scenarie

En af de to Keycloak pods (her keycloak-0) oplever forbindelsesproblemer med databasen, mens keycloak-1 forbliver funktionel.

Event Logfiler viser gentagne parathedssondefejl.

# kubectl get pods -n powerflex | egrep keycloak
keycloak-0                                                1/1     Running     0               22d
keycloak-1                                                1/1     Running     0               22d

# kubectl get events | egrep kube
Events:
  Type     Reason     Age                 From     Message
  ----     ------     ----                ----     -------
  Warning  Unhealthy  12m (x58 over 17h)  keycloak-0  Readiness probe failed: HTTP probe failed with statuscode: 503

Ikonet keycloak pod-logfiler angiver, at det ikke lykkedes at hente JDBC-forbindelser på grund af en anskaffelsestimeout:

# kubectl get logs keycloak-0 -n powerflex
..
2024-11-27 07:01:41,593 INFO  [org.infinispan.CLUSTER] (non-blocking-thread--p2-t126) [Context=actionTokens] ISPN100010: Finished rebalance with members [keycloak-0-17437, keycloak-1-41022], topology id 7
2024-11-27 07:31:03,379 WARN  [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (Timer-0) SQL Error: 0, SQLState: null
2024-11-27 07:31:03,379 ERROR [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (Timer-0) Acquisition timeout while waiting for new connection
2024-11-27 07:31:03,384 ERROR [org.keycloak.services.scheduled.ScheduledTaskRunner] (Timer-0) Failed to run scheduled task ClearExpiredEvents: javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: Unable to acquire JDBC Connection
        at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:154)
        at java.base/java.util.TimerThread.run(Timer.java:506)
Caused by: org.hibernate.exception.GenericJDBCException: Unable to acquire JDBC Connection  <---------
..
Caused by: java.sql.SQLException: Acquisition timeout while waiting for new connection  <--------- 
.. 
Caused by: java.util.concurrent.TimeoutException  <--------- 
..
2024-11-27 09:31:03,476 INFO  [io.smallrye.health] (executor-thread-15) SRHCK01001: Reporting health down status: {"status":"DOWN","checks":[{"name":"Keycloak database connections health check","status":"DOWN","data":{"Failing since":"2024-11-27 07:31:03,477"}}]}
2024-11-27 09:56:03,477 INFO  [io.smallrye.health] (executor-thread-15) SRHCK01001: Reporting health down status: {"status":"DOWN","checks":[{"name":"Keycloak database connections health check","status":"DOWN","data":{"Failing since":"2024-11-27 07:31:03,477"}}]}

Problemet opstår på grund af forkert DNS-konfiguration.

JDBC-forbindelsen, der bruges af keycloak At oprette forbindelse til databasen er afhængig af fortolkning af databasens værtsnavn eller slutpunkt.

Enhver fejlkonfiguration eller fejl i værtsnavnsopløsningen kan forårsage timeouts, når du forsøger at oprette en forbindelse. 

1) Ret DNS-konfigurationen i henhold til operativsystemdokumentationen

a) Hvis RedHat eller CentOS v7,x eller v8,x,

i) Rediger /etc/resolv.conf for at opdatere den korrekte DNS-server på hver MgmtVMs (MVM'er)

ii) Udgår coredns bælg (rke2-coredns-rke2-coredns-xxxxxxxxxx-xxxxx) for at overføre ændringerne af disse bælg:

for x in `kubectl get pods -n kube-system | grep -i rke2-coredns-rke2-coredns | awk '{print $1}' | grep -iv auto`; do kubectl delete pods -n kube-system $x; done

iii) Bekræft, at DNS-ændringer nu afspejles i coredns bælg (der er 2 coredns pods, der er ansvarlige for DNS): 

for x in `kubectl get pods -n kube-system | grep -i rke2-coredns-rke2-coredns | awk '{print $1}' | grep -iv auto`; do echo $x; kubectl exec -it $x -n kube-system -- cat /etc/resolv.conf; echo " "; done

b) Hvis SLES v15.xeller nyere, skal du kontakte support for at følge den interne artikel https://www.dell.com/support/kbdoc/en-us/000227354

2) Genstart keycloak Bælg

kubectl rollout restart statefulset keycloak -n powerflex 

3) Skærm keycloak logfiler for eventuelle yderligere problemer med databaseforbindelsen 

kubectl logs keycloak-0 -n powerflex [-f]
kubectl logs keycloak-1 -n powerflex [-f]