getOS from /etc/os-release first

docs/20_Checks/check_snmp_data.md

@@ -14,7 +14,7 @@ Start the script without parameter to get the help.
 ______________________________________________________________________
 
 CHECK_SNMP_DATA 
-v0.6
+v0.8
 
 (c) Institute for Medical Education - University of Bern
 Licence: GNU GPL 3
@@ -23,22 +23,40 @@ ______________________________________________________________________
 SNMP performance data of Synology storages.
 
 USAGE:
-    ./check_snmp_data -h hostname [-C communitystring] -m method
+    check_snmp_data [options] -h SNMPTARGET
 
 PARAMETERS:
-    -h  hostname       as fqdn or ip address
-    -C  communitystr   optional: community string for snmp; default is public
-    -v                 verbose output
+    -a STRING
+        authentication params for snmpwalk/ snmpget to connect to target; 
+        default: \"-v2c -c public\" (Snmpv2 with community string \"public\")
+    -h SNMPTARGET
+        as fqdn or ip address; default: localhost
+    -f FILE
+        read authentication from config file
+        default: "/etc/icinga2/snmp.cfg"
     -m  method         what to show
                        method is one of ...
+                          about      About... general device infos                     
                           cpu        CPU usage                                         
                           load       System load                                       
-                          netio      Network IO (experimental)                         
+                          mem        Memory status                                     
+                          netio      Network IO                                        
+                          synodisc   Synology Disc usage                               
                           synotemp   Synology NAS temperature                          
-                          disc       Disc usage                                        
+                          synoio     Synology Space IO                                 
+    -v                 verbose output
+
+CONFIG FILE:
+    The config file can be multiline and has the syntax
+    [SNMPTARGET[,target2]]:[auth parameters]
+    The auth parameters set the version and all needed values to connect.
+    Snmp v2 uses a community string.
+    Snmp v3 is highly recommended (you should disable Snmp v2) and needs
+    a user and password.
 
 EXAMPLE:
-    ./check_snmp_data -h 192.168.100.12 -v -m cpu
+    check_snmp_data -h 192.168.100.12 -v -m cpu
+
 
 ```