add prefer_fqdn_over_hostname config option (#859)

the above option allows the user to control the behavior of a distro
hostname selection if both short hostname and FQDN are supplied.
If `prefer_fqdn_over_hostname` is true the FQDN will be selected as
hostname; if false the hostname will be selected

LP: #1921004

1 files changed, 4 insertions, 7 deletions

diff --git a/cloudinit/distros/rhel.py b/cloudinit/distros/rhel.py
index c72f7c17..0c00a531 100644
--- a/cloudinit/distros/rhel.py
+++ b/cloudinit/distros/rhel.py
@@ -50,6 +50,10 @@ class Distro(distros.Distro):
         }
     }
 
+    # Should be fqdn if we can use it
+    # See: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/5/html/deployment_guide/ch-sysconfig  # noqa: E501
+    prefer_fqdn = True
+
     def __init__(self, name, cfg, paths):
         distros.Distro.__init__(self, name, cfg, paths)
         # This will be used to restrict certain
@@ -91,13 +95,6 @@ class Distro(distros.Distro):
             }
             rhel_util.update_sysconfig_file(out_fn, host_cfg)
 
-    def _select_hostname(self, hostname, fqdn):
-        # Should be fqdn if we can use it
-        # See: https://www.centos.org/docs/5/html/Deployment_Guide-en-US/ch-sysconfig.html#s2-sysconfig-network # noqa
-        if fqdn:
-            return fqdn
-        return hostname
-
     def _read_system_hostname(self):
         if self.uses_systemd():
             host_fn = self.systemd_hostname_conf_fn