I had this problem on a new install of OBIEE 12.2.1.4 and, after a fun morning, managed to track it down to OBIEE case sensitivity to server name.
A RedHat Linux 7 server was provided to me. At build time it had an /etc/hosts file with an entry for the local machine. This was all in caps:
192.168.123.456 MACHINENAME.DOMAIN.FOO.BAR MACHINENAME
It also had an /etc/hostname in lower case:
machinename
OBIEE Installed fine - all working. Came to upload RPD and saw OP's error message.
Also saw this in the REST log:
cat $DOMAIN_HOME/bi/servers/bi_server1/logs/bi-lcm-rest.log.0
... oracle.bi.lcm.pojo.si.rpd.RpdHelper INFO - getCustomizationSessionFromLocalOBIS: localNodeHostName info ------->machinename:Null
...
Comparing with another server where I was able to successfully upload the RPD I saw that this should be:
...info ------->machinename:<port>
i.e. where there should be a valid port number for the OBIS service I had Null.
Other threads suggested that similar errors were caused by an incorrect server name somewhere.
To resolve I did the follwing:
Commented out the entry for the local server from /etc/hosts:
# 192.168.123.456 MACHINENAME.DOMAIN.FOO.BAR MACHINENAME
Changed the /etc/hostname entry to be capitalised:
MACHINENAME
Rebooted and it worked.
Ideally I'd go back and rebuild with both /etc/hosts and /etc/hostname changed to lower case. But I haven't time to test this now.
Hope this saves someone else a morning of debugging.