Start fail error log

while i start the service ' sudo service elasticsearch start ' i got the message 'Starting Elasticsearch Server [fail] ' how do i know where is the problem.

I have set my ' jtv-elasticsearch' and ' jtv-node-1' in 'elasticsearch.yml'

Look in /var/log/elasticsearch or /var/log/syslog or something like that.

Thanks for reply, i get the error log from /var/log/syslog 'Error: collectd is respawning too fast - disabled for 300 seconds' nothing else