In 9.0.0 we used the load balancer vip address for the caching, in 10.0.0 we changed to using memcached_servers as a list of servers and removed the lb vip address for memcached however this change was not done for dogpile cache in keystone.
backend_argument = url:{% for host in groups['memcached'] %}{{ hostvars[host]['container_address'] }}:{{ memcached_port|default('11211') }}{% if not loop.last %},{% endif %}:{{ memcached_port }}
In 9.0.0 we used the load balancer vip address for the caching, in 10.0.0 we changed to using memcached_servers as a list of servers and removed the lb vip address for memcached however this change was not done for dogpile cache in keystone.
This is the line that needs to be changed: https://github.com/rcbops/ansible-lxc-rpc/blob/master/rpc_deployment/roles/keystone_common/templates/keystone.conf.j2#L26
Purposed change: