Tilføj "Jobmanager: Skift start-tidspunkt og interval"

Author: agnetemoos

randomize_jobmanager.md

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+---
+title: "Jobmanager: Skift start-tidspunkt og interval"
+parent: "System"
+source: scripts/randomize_jobmanager.sh
+parameters:
+  - name: "Interval"
+    type: "int"
+    default: null
+    mandatory: true
+compatibility: 
+  - "22.04"
+  - "BorgerPC"
+  - "Kiosk"
+---
+
+## Beskrivelse
+Jobmanageren er det program, der tjekker adminsitet efter om BorgerPC'en eller DisplayPC'en har nye scripts til kørsel, og som sender status tilbage, og evt. information om sikkerhedsadvarsler. Jobmanageren kører normalt hvert 5. minut, startende fra 00.
+
+Dette script får i stedet cron.d/bibos_jobmanager jobbet til at starte på et tilfældigt tidspunkt inden for et givent interval.
+
+Eksempel: Intervallet er 5 minutter, så kan jobmanageren potentielt køre hvert 1., 6., 11..56. minut hver time, i stedet for 0., 5., 10...55. minut.
+
+Starttidspunktet er valgt tilfældigt inden for et interval.
+
+Dette script er blevet testet og virker på Ubuntu 22.04.

scripts/randomize_jobmanager.sh

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+#!/usr/bin/env bash
+#================================================================
+# HEADER
+#================================================================
+#% SYNOPSIS
+#+    randomize_jobmanager args $(interval in minutes)
+#%
+#% DESCRIPTION
+#%    This script sets the cron.d/os2borgerpc_jobmanager job to execute
+#%    at a random startup time with a certain interval.
+#%    So if the interval is 5 minutes, the jobmanager could run at
+#%    1, 6, 11...56 every hour, instead of 0, 5, 10 ...55.
+#%
+#================================================================
+#- IMPLEMENTATION
+#-    version         randomize_jobmanager (magenta.dk) 0.0.1
+#-    author          Danni Als
+#-    copyright       Copyright 2018, Magenta Aps"
+#-    license         GNU General Public License
+#-    email           [email protected]
+#-
+#================================================================
+#  HISTORY
+#     2018/15/02 : danni : Script creation
+#
+#================================================================
+# END_OF_HEADER
+#================================================================
+
+INTERVAL=$1
+
+CHECKIN_SCRIPT="/usr/share/os2borgerpc/bin/check-in.sh"
+CRON_PATH="/etc/cron.d/os2borgerpc-jobmanager"
+
+if [ $# -ne 1 ]; then
+    echo "This job takes exactly one parameter."
+    exit 1
+fi
+
+if [ "$INTERVAL" -gt 59 ] || [ "$INTERVAL" -lt 3 ]; then
+    echo "Interval must be between 3 and 59 inclusive."
+    exit 1
+fi
+
+RANDOM_NUMBER=$((RANDOM%INTERVAL+0))
+CRON_COMMAND="$RANDOM_NUMBER,"
+# Generate a pseudo-random number between 0 and 59
+DELAY_IN_SECONDS=$((RANDOM%60))
+
+# Make sure the folder for the check-in script exists
+mkdir --parents "$(dirname "$CHECKIN_SCRIPT")"
+
+cat <<EOF > "$CHECKIN_SCRIPT"
+#!/usr/bin/env sh
+
+sleep $DELAY_IN_SECONDS
+
+/usr/local/bin/jobmanager
+EOF
+
+chmod 700 "$CHECKIN_SCRIPT"
+
+while [ $((RANDOM_NUMBER+INTERVAL)) -lt 60 ]
+do
+    RANDOM_NUMBER=$((RANDOM_NUMBER+INTERVAL))
+    if [ $((RANDOM_NUMBER+INTERVAL)) -ge 60 ]
+    then
+        CRON_COMMAND="$CRON_COMMAND$RANDOM_NUMBER * * * * root $CHECKIN_SCRIPT"
+    else
+        CRON_COMMAND="$CRON_COMMAND$RANDOM_NUMBER,"
+    fi
+done
+echo "$CRON_COMMAND"
+
+# Note: The PATH below is inherited by the scripts jobmanager runs. Fx. they can't find scripts in /usr/local/bin without it
+cat <<EOF > "$CRON_PATH"
+PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+$CRON_COMMAND
+EOF