Munin is a system monitoring tool that generates graphs for various services like Apache, MySQL, Nginx, CPU, Memory, and Disk usage. To set it up, you install the `munin-node` and necessary plugins on each machine (nodes) you want to monitor. Configure the `munin-node.conf` with the node's hostname, allowed central server IP, and node's IP. On the central server, install Munin, configure it to gat