update docs

docs/20_Checks/_index.md

@@ -7,7 +7,7 @@ There is one include script used by all checks:
 
 ## Check scripts
 
-* check_apache_requests
+* [check_apache_requests](check_apache_requests.md)
 * check_backup_one
 * check_ceph_diskfree
 * check_ceph_osd
@@ -15,7 +15,7 @@ There is one include script used by all checks:
 * check_clientbackup
 * check_couchdb-lb
 * [check_cpu](check_cpu.md)
-* check_cronstatus
+* [check_cronstatus](check_cronstatus.md)
 * check_disk-io
 * check_dns_responsetime
 * [check_eol](check_eol.md)
@@ -23,13 +23,13 @@ There is one include script used by all checks:
 * check_haproxy_status
 * check_memory
 * check_netio
-* check_netstat
+* [check_netstat](check_netstat.md)
 * check_opencpu
 * check_packages2install
 * check_proc_mem
 * check_proc_ressources
 * check_proc_zombie
-* check_reboot_required
+* [check_reboot_required](check_reboot_required.md)
 * check_sensuplugins
 * check_smartstatus
 * [check_snmp_data](check_snmp_data.md)

docs/20_Checks/check_netstat.md

+# check netstat
+
+## Introduction
+
+Count number of network connections.
+
+## Syntax
+
+```text
+> ./check_netstat -h
+______________________________________________________________________
+
+CHECK_NETSTAT 
+v1.1
+
+(c) Institute for Medical Education - University of Bern
+Licence: GNU GPL 3
+______________________________________________________________________
+
+Count number of network connections.
+
+SYNTAX:
+check_netstat [ -w value -c value -h ]
+
+    -w VALUE       cpu usage warning level  (default: 75)
+    -c VALUE       cpu usage critical level (default: 90)
+    -h or --help   show this help.
+
+PARAMETERS:
+
+    None.
+
+EXAMPLE:
+check_netstat -w 60 -c 80 -p 40
+
+If there is no -w and -c then the result is always OK.
+
+```
+
+## Examples
+
+Simple call:
+
+```txt
+> ./check_netstat
+OK: NETSTAT - count of connections: 27
+     20 ESTABLISHED
+      4 LISTEN
+      3 TIME_WAIT
+ |established=20;;;0; listen=4;;;0; time-wait=3;;;0;
+ ```