After adding your server on UptimeMonster, you need to install the agent on the server. Click on the All Servers option and it will redirect you to your added server list. Click the server and you will see the agent installation command. You just need to apply the command on your server to install and activate the UptimeMonster agent.
Select your OS and version and then use the command to install the UptimeMonster agent on your server.
Sometimes the agent might not be able to read the CPU core & process list due to permission issues (mostly in some Ubuntu installations), in that case, please edit the agent config and change uid & gid (under the listener section) with a username & group name which has permission to read those data.
File: /etc/umon/umon.cfg
E.G.
[listener]
uid = root
gid = root
And then restart the agent with the following command
service restart umon