=====ICINGA2=====

https://www.thomas-krenn.com/de/wiki/Icinga_Web_2_mit_Icinga_2_verwenden

https://icinga.com/docs/icinga2/latest/doc/01-about/

Schedule downtimes:

https://github.com/Icinga/icinga2/issues/5261

Web2 URL:

https://icinga.local/icingaweb2

Grafana:

https://github.com/Mikesch-mp/icingaweb2-module-grafana/blob/master/doc/02-installation.md

====Install Plugins & NRPE ====

  apt-get install nagios-nrpe-server                                #Nagios Remote Plugin Executor Server                                         -> install on icinga2 server
  apt-get install nagios-nrpe-server monitoring-plugins             #NRPE Server + Plugins for nagios compatible monitoring systems (metapackage) -> install on clients
  apt-get install monitoring-plugins                                #Plugins for nagios compatible monitoring systems (metapackage)
  apt-get install nagios-nrpe-plugin                                #contains e. g. check_nrpe for Icinga Server                                  -> install on clients
  
====Commands====

  service icinga2 checkconfig
  icinga2 daemon -C                                                 #Detailed syntax check icinga config files
  icinga2 daemon --validate
  icinga2 feature list
  icinga2 --version                                                 #Show version and application paths
  icinga2 object list --type Endpoint                               #Show endpoints, possible types: Endpoint, Host, HostGroup, Notification, ScheduledDowntime, Service, ServiceGroup, TimePeriod, User, UserGroup, Zone
  icinga2 object list --type notification
  icinga2 object list --type notificationcommand 
  
<code>
icinga2 feature list
Disabled features: debuglog elasticsearch gelf influxdb livestatus opentsdb perfdata statusdata graphite compatlog graphite
Enabled features:  api checker ido-mysql mainlog notification syslog                                                     #basic features
Enabled features: api checker ido-mysql influxdb mainlog notification perfdata syslog                                    #with influxdb and perfdata

</code>

  find /var/spool/icinga2/perfdata -type f -ctime +90 -exec rm {} \;

Basic features:

  checker        #icinga2 
  command        #icinga2                                         #DEPRECATED and will be removed in future releases
  ido-mysql      #icingaweb2
  notification   #icinga2

  api            #Just needed when working with zones



====NRPE Server====

===Encryption===
  
"No ssl" (/etc/default/nagios-nrpe-server):

  DAEMON_OPTS="--no-ssl"                     #default: '#DAEMON_OPTS="--no-ssl"'
  NRPE_OPTS="-n"                             #on debian (10) system/ raspian, >=ubuntu20.04

===NRPE-Checks===

Examples Linux (/etc/nagios/nrpe.cfg):

<code>
#####Set Port:
server_port=5666
#####Add IP Icinga-Host:
allowed_hosts=127.0.0.1,10.5.8.10

#####################Linux-default###############################################
command[check_users]=/usr/lib/nagios/plugins/check_users -w 5 -c 10
command[check_load]=/usr/lib/nagios/plugins/check_load -w 15,10,5 -c 30,25,20
command[check_zombie_procs]=/usr/lib/nagios/plugins/check_procs -w 5 -c 10 -s Z
command[check_total_procs]=/usr/lib/nagios/plugins/check_procs -w 600 -c 800

command[check_disk_root]=/usr/lib/nagios/plugins/check_disk -w 5% -c 2% -p /
command[check_disk_boot]=/usr/lib/nagios/plugins/check_disk -w 5% -c 2% -p /boot
command[check_disk_tmp]=/usr/lib/nagios/plugins/check_disk -w 5% -c 2% -p /tmp
command[check_disk_var]=/usr/lib/nagios/plugins/check_disk -w 5% -c 2% -p /var
command[check_disk_usr]=/usr/lib/nagios/plugins/check_disk -w 5% -c 2% -p /usr
command[check_disk_home]=/usr/lib/nagios/plugins/check_disk -w 5% -c 2% -p /home
#command[check_hda1]=/usr/lib/nagios/plugins/check_disk -w 20% -c 10% -p /dev/hda1
</code>

===Commands===

  /usr/lib/nagios/plugins/check_nrpe -H hostname
  /usr/lib/nagios/plugins/check_nrpe -n -H hostname                                             #Do no use SSL
  /usr/lib/nagios/plugins/check_nrpe -n -H hostname -t 60 -c check_apt
  
===Logging===

  icinga2 feature enable debuglog
  tail -f /var/log/icinga2/icinga2.log
  tail -f /var/log/icinga2/icinga2.log /var/log/icinga2/debug.log

====SNMP====

Test:

  snmpget -v1 -c "public" "192.168.1.20" -mALL
  snmpget -v1 -c "public" "192.168.1.20" -mALL 1.3.6.1.4.1.24681.1.2.17.1.4.1                        #qnap disk "TotalSize"
  snmpwalk -v 2c -c "public" "192.168.1.20" ifIndex
  
Mips (Ubuntu/ Debian):

  sudo apt-get install snmp-mibs-downloader    
  sudo download-mibs

Fix Qnap TS 212:

https://docs.linuxconsulting.mn.it/notes/net-snmp-errors

  sudo wget http://www.iana.org/assignments/ianaippmmetricsregistry-mib/ianaippmmetricsregistry-mib -O /usr/share/mibs/iana/IANA-IPPM-METRICS-REGISTRY-MIB
  sudo wget http://pastebin.com/raw.php?i=p3QyuXzZ -O /usr/share/mibs/ietf/SNMPv2-PDU
  sudo wget http://pastebin.com/raw.php?i=gG7j8nyk -O /usr/share/mibs/ietf/IPATM-IPMC-MIB


====Zones & Satellite====

https://icinga.com/docs/icinga2/latest/doc/06-distributed-monitoring/

  icinga2 node wizard
  
====https====

  a2ensite default-ssl
  a2enmod ssl
  service apache2 restart
  systemctl status apache2.service
  
Force redirect http -> https:

https://www.tmade.de/wiki/doku.php?id=server:apache#redirect

====k8s====

https://github.com/T-Systems-MMS/check_kubernetes 

=====Examples=====

  assign where (host.address || host.address6)
  assign where (host.address || host.address6) || host.vars.os == "Linux"
  
===== Notification & Mail ======

To send emails the program "mail" and an mta like "postfix" is required. You can install it on debian based system such as:

  apt install mailutils 
  apt install postfix
=====Windows=====

Client:

  NSClient++ (x64)