Merge pull request #101 from TDT-AG/tdt-bootup-delay

Add random bootup delay #100

Author: nemesifier

README.rst

@@ -71,6 +71,7 @@ UCI configuration options must go in ``/etc/config/openwisp``.
 - ``key``: key required to download the configuration
 - ``hardware_id_script``: custom script to read out a hardware id (e.g. a serial number), read more about this feature in `Hardware ID`_
 - ``hardware_id_key``: whether to use the hardware id for key generation or not, defaults to ``1``
+- ``bootup_delay``: maximum value in seconds of a random delay after bootup, defaults to ``0``, see `Bootup Delay`_
 - ``unmanaged``: list of config sections which won't be overwritten, see `Unmanaged Configurations`_
 - ``capath``: value passed to curl ``--capath`` argument, by default is empty; see also `curl capath argument <https://curl.haxx.se/docs/manpage.html#--capath>`_
 - ``cacert``: value passed to curl ``--cacert`` argument, by default is empty; see also `curl cacert argument <https://curl.haxx.se/docs/manpage.html#--cacert>`_
@@ -166,6 +167,16 @@ generation then set ``hardware_id_key`` to ``0``.
 
 For settings in ``django-netjsonconfig`` related to the hardware id, take a look at the `README <https://github.com/openwisp/django-netjsonconfig/#netjsonconfig-hardware-id-enabled>`_
 
+Bootup Delay
+------------
+
+The option ``bootup_delay`` can be used to make the agent wait for a random amount of seconds after the bootup of
+the device. Allowed random values range from 0 up to the value of ``bootup_delay``. The delay is applied only after the
+device has been registered.
+
+The random bootup delay reduces the load on the OpenWISP controller when a large amount of devices boot up at the
+same time after a power failure, all trying to connect to the controller.
+
 Unmanaged Configurations
 ------------------------
 

openwisp-config/files/openwisp-nossl.config

@@ -14,6 +14,7 @@ config controller 'http'
 	#option test_script '/usr/sbin/mytest'
 	#option hardware_id_script '/usr/sbin/read_hw_id'
 	#option hardware_id_key '1'
+	#option bootup_delay '0'
 	option uuid ''
 	option key ''
 	# curl options

openwisp-config/files/openwisp-ssl.config

@@ -14,6 +14,7 @@ config controller 'http'
 	#option test_script '/usr/sbin/mytest'
 	#option hardware_id_script '/usr/sbin/read_hw_id'
 	#option hardware_id_key '1'
+	#option bootup_delay '0'
 	option uuid ''
 	option key ''
 	# curl options

openwisp-config/files/openwisp.agent

@@ -13,6 +13,7 @@ while [ -n "$1" ]; do
 		--consistent-key) export CONSISTENT_KEY="$2"; shift;;
 		--hardware-id-script) export HARDWARE_ID_SCRIPT="$2"; shift;;
 		--hardware-id-key) export HARDWARE_ID_KEY="$2"; shift;;
+		--bootup-delay) export BOOTUP_DELAY="$2"; shift;;
 		--merge-config) export MERGE_CONFIG="$2"; shift;;
 		--unmanaged) export UNMANAGED="$2"; shift;;
 		--test-config) export TEST_CONFIG="$2"; shift;;
@@ -61,6 +62,7 @@ MERGE_CONFIG=${MERGE_CONFIG:-1}
 TEST_CONFIG=${TEST_CONFIG:-1}
 CONSISTENT_KEY=${CONSISTENT_KEY:-1}
 HARDWARE_ID_KEY=${HARDWARE_ID_KEY:-1}
+BOOTUP_DELAY=${BOOTUP_DELAY:-0}
 CONNECT_TIMEOUT=${CONNECT_TIMEOUT:-15}
 MAX_TIME=${MAX_TIME:-30}
 MAC_INTERFACE=${MAC_INTERFACE:-eth0}
@@ -76,6 +78,7 @@ REGISTRATION_PARAMETERS="$WORKING_DIR/registration_parameters"
 TEST_CHECKSUM="$WORKING_DIR/test_checksum"
 STATUS_REPORT="$WORKING_DIR/status_report"
 APPLYING_CONF="$WORKING_DIR/applying_conf"
+BOOTUP="$WORKING_DIR/bootup"
 REGISTRATION_URL="$URL/controller/register/"
 UNMANAGED_DIR="$WORKING_DIR/unmanaged"
 FETCH_COMMAND="curl -s --connect-timeout $CONNECT_TIMEOUT --max-time $MAX_TIME"
@@ -557,6 +560,18 @@ if [ -z "$UUID" ] || [ -z "$KEY" ]; then
 	do
 		sleep $(expr $INTERVAL / 4)
 	done
+	touch "$BOOTUP"
+else
+	# add delay only after bootup, not after registration or restart
+	if [ "$BOOTUP_DELAY" != "0" ] && [ ! -f "$BOOTUP" ]; then
+		# random bootup delay between 0..300 seconds
+		DELAY="$(($RANDOM%$BOOTUP_DELAY))"
+		logger "Delaying startup for $DELAY seconds..." \
+				 -t openwisp \
+				 -p daemon.info
+		sleep $DELAY
+		touch "$BOOTUP"
+	fi
 fi
 
 # these variables are evaluated here because "register()" might set UUID and KEY

openwisp-config/files/openwisp.init

@@ -17,6 +17,7 @@ start_service() {
 	consistent_key=$(config_get http consistent_key)
 	hardware_id_script=$(config_get http hardware_id_script)
 	hardware_id_key=$(config_get http hardware_id_key)
+	bootup_delay=$(config_get http bootup_delay)
 	unmanaged=$(config_get http unmanaged)
 	merge_config=$(config_get http merge_config)
 	test_config=$(config_get http test_config)
@@ -39,6 +40,7 @@ start_service() {
 	if [ $consistent_key ]; then consistent_key="--consistent-key $consistent_key"; fi
 	if [ $hardware_id_script ]; then hardware_id_script="--hardware-id-script $hardware_id_script"; fi
 	if [ $hardware_id_key ]; then hardware_id_key="--hardware-id-key $hardware_id_key"; fi
+	if [ $bootup_delay ]; then bootup_delay="--bootup-delay $bootup_delay"; fi
 	if [ -n "$unmanaged" ]; then
 		# replace spaces with commas to avoid problems when
 		# passing this arg to procd_set_param command
@@ -75,10 +77,10 @@ start_service() {
 	procd_open_instance
 	procd_set_param command $PROG $url $interval $verify_ssl $uuid $key $shared_secret \
 	                        $consistent_key $hardware_id_script $hardware_id_key \
-	                        $unmanaged $merge_config $test_config $test_script \
-	                        $connect_timeout $max_time $capath $cacert $mac_interface \
-	                        $management_interface $pre_reload_hook $post_reload_hook \
-	                        $post_registration_hook
+	                        $bootup_delay $unmanaged $merge_config $test_config \
+	                        $test_script $connect_timeout $max_time $capath $cacert \
+	                        $mac_interface $management_interface $pre_reload_hook \
+	                        $post_reload_hook $post_registration_hook
 	procd_set_param respawn
 	procd_close_instance
 	logger -s "$PROG_NAME started" \