Following the HA setup for HAProxy in regards to Telemetry services (Ceilometer), after installing Ceilometer the hosts show listening on tcp/8777 but the HAProxy admin page shows them as being down. In turn, this causes an error in Horizon which states unable to retrieve the list of Monitoring resource list. After making the following change to HAProxy everything comes up as it should and the ability to view objects is available.
listen ceilometer_api_cluster
bind {{ openstack_services_vip }}:8777
balance source
option tcpka
# option httpchk ###Fails when set to httpchk
option tcplog
{% for host in groups['openstack-controller-nodes'] %}
server {{ host }} {{ host }}:8777 check inter 2000 rise 2 fall 5
{% endfor %}
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Release: 0.0.1 on 2015-11-15 23:15
SHA: 419733138b3f98c79a25be1092c4efc5d2bd1e36
Source: http://git.openstack.org/cgit/openstack/ha-guide/tree/doc/ha-guide/source/controller-ha-haproxy.rst
URL: http://docs.openstack.org/ha-guide/controller-ha-haproxy.html
It seems valid point, although I cannot bring any arguments why one should NOT use httpchk for ceilomter but should use it for the rest of API services in OpenStack