Unable to add multiple host entries against the same IP address and vice versa in a non-DNS IPv4 environment

In a non-DNS IPv4 environment, if you try to add custom host entries with a different FQDN against the same IP address or if you add custom host entries with a different IP address against the same FQDN, the operation is not permitted.

Also, manually added entries get deleted from the /etc/hosts file in case of any resiliency-related operations (such as, failover) occur. (4066927)

Workaround:

If duplicate IP/ FQDN needs to be added, add the entries to /etc/hosts on each node.

You have to add the entries again in /etc/hosts of each node if any resiliency-related operations occur.