That's very interestingthradec. I just took a look at your dig response (the one that you pasted previously in this thread) and it seems your using DNS A Records (not SRVs). Therefore, you should not be affected by this change. Maybe there's something more that changed in JGroups that fixed this behavior. belaban What do you think?
If this issue happens again in your cluster, would you be able to dump dig output and Pod IPs? I start to think that maybe somehow those two get out of sync?
I have good news, after the JGroups upgrade to version 4.0.19 the warning disappeared and everything seems working fine.
@Thomas thanks a lot the advice
@Bela/@Sebastian do you think it is fine to use a newer version of jgroups then originally distributed with wildfly?
Thanks Tomas and Thomas! This does seem to fix the issue. Here's the Dockerfile I'm using:
FROM jboss/keycloak:5.0.0 ADD https://netix.dl.sourceforge.net/project/javagroups/JGroups/4.0.19.Final/jgroups-4.0.19.Final.jar /opt/jboss/keycloak/modules/system/layers/base/org/jgroups/main/ USER root RUN chmod 644 /opt/jboss/keycloak/modules/system/layers/base/org/jgroups/main/jgroups-4.0.19.Final.jar RUN chown jboss:root /opt/jboss/keycloak/modules/system/layers/base/org/jgroups/main/jgroups-4.0.19.Final.jar RUN rm -f /opt/jboss/keycloak/modules/system/layers/base/org/jgroups/main/jgroups-4.0.15.Final.jar USER jboss RUN sed -i 's/jgroups-4.0.15.Final.jar/jgroups-4.0.19.Final.jar/' /opt/jboss/keycloak/modules/system/layers/base/org/jgroups/main/module.xml
Thanks for the useful snippet!
Btw. with recent docker versions this should do the trick as well:
# Patch JGroups Module for https://developer.jboss.org/message/988797?et=watches.email.thread#988797
ADD --chown=jboss:jboss https://netix.dl.sourceforge.net/project/javagroups/JGroups/4.0.19.Final/jgroups-4.0.19.Final.jar /opt/jboss/keycloak/modules/system/layers/base/org/jgroups/main/
RUN sed -i 's/jgroups-4.0.15.Final.jar/jgroups-4.0.19.Final.jar/' /opt/jboss/keycloak/modules/system/layers/base/org/jgroups/main/module.xml
That's much tidier. Thanks for improving my Docker fu.