ambari agent failed to start Permission denied

[#1]

I want to manually install ambari-agent in the same host that contains ambari-server when I try ambari-agent start it gives me "bash: /var/lib/ambari-agent/bin/ambari-agent: Permission denied" I run the command with root permission, how to start ambari-agent

any help, please

[#2]

Yes, That's correct Answer and it works. But do we have any other workaround, as we have disabled exec due to security reasons. So how to achieve this.?