Your configuration is written for an agent named "tier1" but your agent is
instead starting with name "agent". Thereby it does not pick up any configs
cause the configs are for another agent.
Are you using CM to manager Flume agents? You can specify per-agent names
in its CM -> Flume -> Configuration page if so, or alter the config of the
agent to use "agent" in place of "tier1".
If you're not using CM, then please read:
http://www.cloudera.com/documentation/enterprise/latest/topics/cdh_ig_flume_files.html#topic_12_8,i.e. edit the file /etc/default/flume-ng-agent to change the agent's name
(currently "agent") to match the config "tier1", or conversely edit the
configuration under /etc/flume-ng/conf/flume.conf to use the agent's name
"agent" in place of "tier1".