RGW: Add resolve cname configuration parameter

Adds a switch to enable bucket resolution using DNS CNAME provided
by the client's HTTP headers.

group_vars/all.yml.sample

@@ -289,6 +289,7 @@ dummy:
 ## Rados Gateway options
 #
 #radosgw_dns_name: your.subdomain.tld # subdomains used by radosgw. See http://ceph.com/docs/master/radosgw/config/#enabling-subdomain-s3-calls
+#radosgw_resolve_cname: false # enable for radosgw to resolve DNS CNAME based bucket names
 #radosgw_civetweb_port: 8080 # on Infernalis we get: "set_ports_option: cannot bind to 80: 13 (Permission denied)"
 #radosgw_civetweb_bind_ip: "{{ ansible_default_ipv4.address }}"
 #radosgw_civetweb_num_threads: 50

roles/ceph-common/defaults/main.yml

@@ -281,6 +281,7 @@ mds_max_mds: 3
 ## Rados Gateway options
 #
 #radosgw_dns_name: your.subdomain.tld # subdomains used by radosgw. See http://ceph.com/docs/master/radosgw/config/#enabling-subdomain-s3-calls
+radosgw_resolve_cname: false # enable for radosgw to resolve DNS CNAME based bucket names
 radosgw_civetweb_port: 8080 # on Infernalis we get: "set_ports_option: cannot bind to 80: 13 (Permission denied)"
 radosgw_civetweb_bind_ip: "{{ ansible_default_ipv4.address }}"
 radosgw_civetweb_num_threads: 50

roles/ceph-common/templates/ceph.conf.j2

@@ -112,6 +112,7 @@ rgw socket path = /tmp/radosgw-{{ hostvars[host]['ansible_hostname'] }}.sock
 log file = /var/log/ceph/{{ cluster }}-rgw-{{ hostvars[host]['ansible_hostname'] }}.log
 rgw data = /var/lib/ceph/radosgw/{{ cluster }}-rgw.{{ hostvars[host]['ansible_hostname'] }}
 rgw frontends = civetweb {{ radosgw_civetweb_options }}
+rgw resolve cname = {{ radosgw_resolve_cname | bool }}
 {% if radosgw_keystone %}
 rgw keystone url = {{ radosgw_keystone_url }}
 rgw keystone api version = {{ radosgw_keystone_api_version }}