Because Java caches DNS lookups indefinitely by default, and as such doesn’t honor the DNS TTL, for the high availability setup then DNS cache should be disabled on the JVM of the Alfresco host server. This can lead to stale IP addresses of the storage hosts and this will lead to connection issues to the content store.
If this is not the case, the object-storage amp’s code will raise a warning in the logs.
To disable the DNS cache on the JVM, one needs to set the security properties networkaddress.cache.ttl and networkaddress.cache.negative.ttl to 0. This can be done by creating an additional security configuration file:
networkaddress.cache.ttl=0
networkaddress.cache.negative.ttl=0
This configuration file should be available on the server or container and should be added to the JVM by adding the following option to the tomcat startup command:
java -Djava.security.properties=<path-to-additional-security-config-file> ...