cluster creation fails in k8s when fqdn dns name are used

[rama-krishna-rayudu]

Environemnt: Azure Kubernetes Cluster
Node: 3 node basic cluster
Reproducible: every time DNS names are used.
workaround: use IPs instead of hostnames.

We have made riak-kv-1 as a co-ordinator and trying to join the riak-kv-0 with the DNS names to form a riak cluster.
Following are the steps:

[root@riak-kv-0 /]# hostname --fqdn
riak-kv-0.riak-svc.default.svc.cluster.local
[root@riak-kv-0 /]# ping riak-kv-1.riak-svc.default.svc.cluster.local
PING riak-kv-1.riak-svc.default.svc.cluster.local (172.18.64.108) 56(84) bytes of data.
64 bytes from riak-kv-1.riak-svc.default.svc.cluster.local (172.18.64.108): icmp_seq=1 ttl=62 time=1.44 ms
64 bytes from riak-kv-1.riak-svc.default.svc.cluster.local (172.18.64.108): icmp_seq=2 ttl=62 time=0.823 ms
64 bytes from riak-kv-1.riak-svc.default.svc.cluster.local (172.18.64.108): icmp_seq=3 ttl=62 time=1.37 ms
64 bytes from riak-kv-1.riak-svc.default.svc.cluster.local (172.18.64.108): icmp_seq=4 ttl=62 time=0.849 ms
^C
--- riak-kv-1.riak-svc.default.svc.cluster.local ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3010ms
rtt min/avg/max/mdev = 0.823/1.125/1.449/0.290 ms
[root@riak-kv-0 /]# riak start
[root@riak-kv-0 /]# riak ping
pong
[root@riak-kv-0 /]# riak admin cluster status
---- Cluster Status ----
Ring ready: true

+-----------------------+------+-------+-----+-------+
| node |status| avail |ring |pending|
+-----------------------+------+-------+-----+-------+
| (C) riak@172.18.64.60 |valid | up |100.0| -- |
+-----------------------+------+-------+-----+-------+

Key: (C) = Claimant; availability marked with '!' is unexpected
[root@riak-kv-0 /]# riak admin cluster join riak@riak-kv-1.riak-svc.default.svc.cluster.local
Node riak@riak-kv-1.riak-svc.default.svc.cluster.local is not reachable!
[root@riak-kv-0 /]#