| basics | linux | crontab | ftp | .htaccess | nfs |
| ntp | raid | rsync | ssh | ssl | |
| vi | |||||
| os | android | debian | centos | freebsd | mac |
| command line email | mailman | postfix | zimbra | ||
| applications | apache | amanda | bind | bitcoin | dhcp |
| jabber | nginx | proftpd | pureftp | redmine | |
| samba | vsftp | ||||
| backup | amanda | backuppc | bacula | raid | |
| content mgmt CMS | drupal | freeside3 | joomla | mediwiki | liferay |
| wordpress | |||||
| code | bash | go language | java | php | python |
| git | subversion | ||||
| database | cassandra | mariadb | mongodb | mysql | postgresql |
| monitoring | elk stack | kvm monitoring | icinga | librenms | nagios |
| mrtg/snmp | syslog-ng | rrd | snort | TAP / mirror | |
| tripwire | wireshark / tshark | zabbix | |||
| security | eset | hack tools | nmap | openvas | pineapple |
| networking | cisco | hp procurve | forensics | fq_codel | iperf |
| freeradius | juniper junOS | juniper screenOS | linux router | mac network | |
| mikrotik | mikrotikvpn | openvpn | transparent monitor | wake on lan | |
| proxy | approx | squid proxy | |||
| virtualization | kvm | virtualbox | vmware | xen | |
| low power computing | beaglebone black | guruplug | raspberry pi | sheevaplug | |
| RF | cell modems | SDR |