Sending RPCs with incorrect data should result in error response. However this is not happens for Keystore RPCs for some reason. In attached Postman collections you can find two examples of add-keystore-entry RPC - one with valid key data and one with invalid. Both RPCs return 204 response and added to datastore that can be confirmed by using GET request from the same collection. For invalid key we can see error(karaf log attached) and this key won't be stored in Java Keystore (for example org.opendaylight.netconf.client.mdsal.impl.DefaultSslContextFactoryProvider has NetcofKeystore parameter that used for TLS connection). This can result in errors if invalid key is used for establishing connection after.