Installation of RHDS 11 fails on RHEL8 server with IPv6 disabled

Issue

• Installation of RHDS 11 fails on RHEL8 server with IPv6 disabled
• Error observed during Directory Instance .

DEBUG: PASSED: root user checking
DEBUG: [Errno 97] Address family not supported by protocol
Traceback (most recent call last):
  File "/usr/sbin/dscreate", line 75, in <module>
    result = args.func(inst, log, args)
  File "/usr/lib/python3.6/site-packages/lib389/cli_ctl/instance.py", line 71, in instance_create
    if sd.create_from_inf(args.file):
  File "/usr/lib/python3.6/site-packages/lib389/instance/setup.py", line 527, in create_from_inf
    self.create_from_args(general, slapd, backends, self.extra)
  File "/usr/lib/python3.6/site-packages/lib389/instance/setup.py", line 643, in create_from_args
    self._prepare_ds(general, slapd, backends)
  File "/usr/lib/python3.6/site-packages/lib389/instance/setup.py", line 611, in _prepare_ds
    assert_c(socket_check_open('::1', slapd['port']) is False, "port %s is already in use, or missing NET_BIND_SERVICE" % slapd['port'])
  File "/usr/lib/python3.6/site-packages/lib389/utils.py", line 1131, in socket_check_open
    with closing(socket.socket(socket.AF_INET6, socket.SOCK_STREAM)) as sock:
  File "/usr/lib64/python3.6/socket.py", line 144, in __init__
    _socket.socket.__init__(self, family, type, proto, fileno)
OSError: [Errno 97] Address family not supported by protocol
ERROR: Error: [Errno 97] Address family not supported by protocol