Enabling SNMPv2c on a Cisco Router, for example.
enable configure terminal snmp-server community PASSWORD_STRING ro snmp-server community PASSWORD_STRING rw
Now you can use any tool to monitor and manage your device, such as ManageEngine MibBrowser Free Tool [Link].
For monitor applications, there are big players such as OpenNMS [Link], Zabbix [Link], Nagios [Link], SolarWinds, Airwave, PRTG, etc.
The SYSLOG centralizes the log of the network devices in a server.
After setting up the server SYSLOG server, for example, Kiwi Syslog Server Free Edition from SolarWinds [Link], set up the network devices to sent log information to the server.
enable clock set 13:45:00 02 Mar 2021 configure terminal service timestamps log datetime msec logging 10.0.0.254 logging trap informational
Staring the process of setting the clock is a good practice to prevent sending logs to the server that will make the debugging very confusing.