Monitoring

Monitoring systems are responsible to collect, show and generate alarms in monitored devices such us: servers or network devices.

Tools
Linux includes different tools for collecting, observe and monitoring systems metrics or performance, such as: sysstat, atop, dstat and vmstat. Some of them include recording and alerting capabilities while others just visualization capabilities.

Monitoring solutions
Zabbix and Nagios have been historically tools used to perform monitoring across different servers or devices. Other tools included Icinga (Nagios fork), Prometheus and Netdata.

Alerting capabilities
Netdata support email alerts and is planned to add support to Slack.

prometheus alertmanager support different notifications methods

vmstat
vmstat 1 procs ---memory-- ---swap-- -io -system-- --cpu- r b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st 10  2 837532 459608  64052 23976592    1    2   992  1714    1    1 23  5 70  2  0 1 0 837532 421692  64052 24014288    0    0 33444  2280 20629 33647 38  5 55  2  0 2  1 837532 496892  64012 23937976    0   32 56464  2224 19104 35788 24  4 70  3  0 7  0 837532 435928  64020 23999028    0    0 55584  2272 22717 37604 32  5 60  2  0 10  8 837532 411988  64020 24021820    0    0 21532 270348 25256 33189 41  6 38 16  0 8  3 837532 447948  63984 23986276    0    0 28788 20560 27664 42733 39  7 41 13  0

Activities

 * 1) Review wikipedia list of software monitors: https://en.wikipedia.org/wiki/System_monitor#List_of_software_monitors
 * 2) Review wikiversity articles covering system, software or network monitors: monit, Nagios, Prometheus (software), netdata, sar and Zabbix
 * 3) Identify key differences between network monitoring, system monitoring and application performance monitoring (APM).
 * 4) Implement a solution to detect disk array failures: System administration/ProLiant/Remove a disk from your redundant storage array and review OS logs
 * 5) Monitoring disk space:
 * 6) Configure sysstat for collecting disk space usage
 * 7) Configure Netdata with diskspace plugin
 * 8) Monitor your RAID devices:
 * 9) Software RAIDs: mdadm
 * 10) Hardware RAIDs: HPE Array Controllers