datadog-agent.service should not enforce user

[vkukk]

Regarding to this old issue which is still not resolved in 5.22 #2033

Workaround to that issue is to change supervisor.conf to run supervisord and collector as user root. However, on CentOS/RHEL 7 with systemd, the packaged /usr/lib/systemd/system/datadog-agent.service enforces user dd-agent.

dd-agent/packaging/datadog-agent.service

Line 7 in 8828728

User=dd-agent

This results in non-working service (collector not running) when changing supervisor.conf to run some processes as root.

Additional environment details (Operating System, Cloud provider, etc):
CentOS/RHEL 7 (possibly all other systemd distributions as well.

Steps to reproduce the issue:

1. Install on CentOS 7
2. Change /etc/dd-agent/supervisor.conf services [supervisord] and [program:collector] users to root
3. systemctl start datadog-agent.service fails

To solve this issue, remove enforcing user dd-agent in datadog-agent.service. Just removing line

dd-agent/packaging/datadog-agent.service

Line 7 in 8828728

User=dd-agent

is enough.

Then supervisord and collector will be started as root.
root 22062 0.2 0.3 199856 15376 ? Ss 15:16 0:00 /opt/datadog-agent/embedded/bin/python /opt/datadog-agent/bin/supervisord -c /etc/dd-agent/supervisor.conf
dd-agent 22065 1.5 0.9 176016 37292 ? S 15:16 0:00 /opt/datadog-agent/embedded/bin/python /opt/datadog-agent/agent/ddagent.py
dd-agent 22066 1.3 0.8 222040 34228 ? Sl 15:16 0:00 /opt/datadog-agent/embedded/bin/python /opt/datadog-agent/agent/dogstatsd.py --use-local-forwarder
root 22072 5.3 1.0 454580 44340 ? Sl 15:16 0:01 /opt/datadog-agent/embedded/bin/python /opt/datadog-agent/agent/agent.py foreground --use-local-forwarder