[warm boot] move warm reboot/fast reboot knowledge to syncd service s…

…cript (sonic-net#372)

* [warm boot] set warm boot flag before killing swss docker

Kill swss docker will cause service swss to fail, systemctrl will then
stop swss as result. If the flag is not set, swss will also stop syncd
without letting syncd to warm shutdown.

Signed-off-by: Ying Xie <ying.xie@microsoft.com>

* [fast/warm reboot] let syncd service handle different types of shutdowns

Signed-off-by: Ying Xie <ying.xie@microsoft.com>

* [warm/fast reboot] stop execution after error

Signed-off-by: Ying Xie <ying.xie@microsoft.com>

* [warm boot] set warm boot flag earlier and clear it on error

Signed-off-by: Ying Xie <ying.xie@microsoft.com>

* [warm boot] stop syncd before backing up database

Signed-off-by: Ying Xie <ying.xie@microsoft.com>

scripts/fast-reboot

@@ -1,9 +1,20 @@
-#!/bin/bash
+#!/bin/bash -e
 
 REBOOT_USER=$(logname)
 REBOOT_TIME=$(date)
 REBOOT_CAUSE_FILE="/var/cache/sonic/reboot-cause.txt"
 REBOOT_TYPE=$(basename $0)
+WARM_DIR=/host/warmboot
+
+function clear_warm_boot()
+{
+    config warm_restart disable || /bin/true
+
+    TIMESTAMP=`date +%Y%m%d-%H%M%S`
+    if [[ -f ${WARM_DIR}/config_db.json ]]; then
+        mv -f ${WARM_DIR}/config_db.json ${WARM_DIR}/config_db-${TIMESTAMP}.json || /bin/true
+    fi
+}
 
 # Check reboot type supported
 BOOT_TYPE_ARG="cold"
@@ -13,6 +24,8 @@ case "$REBOOT_TYPE" in
         ;;
     "warm-reboot")
         BOOT_TYPE_ARG="warm"
+        trap clear_warm_boot EXIT HUP INT QUIT TERM KILL ABRT ALRM
+        config warm_restart enable system
         ;;
     *)
         echo "Not supported reboot type: $REBOOT_TYPE" >&2
@@ -119,15 +132,15 @@ fi
 # Kill swss dockers
 docker kill swss
 
+# syncd service stop is capable of handling both warm/fast/cold shutdown
+systemctl stop syncd
+
 # Warm reboot: dump state to host disk
 # Note: even if syncd changed ASIC_DB before killed, we don't care
 if [[ "$REBOOT_TYPE" = "warm-reboot" ]]; then
-    # Set whole system warm reboot flag
-    config warm_restart enable system
     # Dump redis content to directory
     # Note: don't use pretty mode redis-dump (1.1) since there is a known bug with key pattern
     DUMP_CMD="redis-dump -s /var/run/redis/redis.sock"
-    WARM_DIR=/host/warmboot
     mkdir -p $WARM_DIR
     # Note: requiring redis-dump-load
     # Save applDB in /host/warm-reboot/appl_db.json
@@ -144,23 +157,6 @@ if [[ "$REBOOT_TYPE" = "warm-reboot" ]]; then
     $DUMP_CMD -d 3 -o $WARM_DIR/loglevel_db.json
 fi
 
-if [[ "$REBOOT_TYPE" = "warm-reboot" ]]; then
-    # Gracefully stop syncd for warm-reboot
-    systemctl stop syncd
-elif [[ "$REBOOT_TYPE" = "fast-reboot" ]]; then
-    # syncd graceful stop for fast-reboot is supported only for Broadcom platforms only for now
-    if [[ "$sonic_asic_type" = 'broadcom' ]]; then
-        # Gracefully stop syncd
-        docker exec -i syncd /usr/bin/syncd_request_shutdown --cold > /dev/null
-
-        # Check that syncd was stopped
-        while docker top syncd | grep -q /usr/bin/syncd
-        do
-            sleep 0.1
-        done
-    fi
-fi
-
 # Kill other containers to make the reboot faster
 docker ps -q | xargs docker kill > /dev/null