[201811] Check platform reboot cause to see if any reset happened during fast/warm-reboot (#8912)

[201811] Check platform reboot cause to see if any reset happened during fast/warm-reboot

Why I did it
To recover syncd and swss from any cold reset during fast/warm-reboot

How I did it
Check platform reboot-cause to see if any cold reset happens for fast-reboot power up

How to verify it
Manual test

files/build_templates/database.service.j2

@@ -2,6 +2,7 @@
 Description=Database container
 Requires=docker.service
 After=docker.service
+After=rc-local.service
 
 [Service]
 User=root

files/build_templates/docker_image_ctl.j2

@@ -5,6 +5,17 @@ function getMountPoint()
     echo $1 | python -c "import sys, json, os; mnts = [x for x in json.load(sys.stdin)[0]['Mounts'] if x['Destination'] == '/usr/share/sonic/hwsku']; print '' if len(mnts) == 0 else os.path.basename(mnts[0]['Source'])" 2>/dev/null
 }
 
+function isPlatformReset()
+{
+    output=$(python -c "import sonic_platform.platform; p = sonic_platform.platform.Platform(); c = p.get_chassis(); hw_rc_major, hw_rc_minor = c.get_reboot_cause(); print(hw_rc_major)" 2>/dev/null)
+
+    if [[ "${output}" != "Non-Hardware" ]]; then
+        return 0
+    else
+        return 1
+    fi
+}
+
 function getBootType()
 {
     # same code snippet in files/scripts/syncd.sh
@@ -21,6 +32,9 @@ function getBootType()
     *)
         TYPE='cold'
     esac
+    if isPlatformReset; then
+        TYPE='cold'
+    fi
     echo "${TYPE}"
 }
 
@@ -59,7 +73,7 @@ function postStartAction()
         fi
 
         if [[ "$BOOT_TYPE" == "fast" ]]; then
-            # set the key to expire in 3 minutes
+            # set the FAST_REBOOT|system key to expire in 3 minutes
             redis-cli -n 6 SET "FAST_REBOOT|system" "1" "EX" "180"
         fi
 

files/build_templates/sonic_debian_extension.j2

@@ -268,6 +268,11 @@ sudo cp $IMAGE_CONFIGS/process-reboot-cause/process-reboot-cause.service  $FILES
 sudo LANG=C chroot $FILESYSTEM_ROOT systemctl enable process-reboot-cause.service
 sudo cp $IMAGE_CONFIGS/process-reboot-cause/process-reboot-cause $FILESYSTEM_ROOT/usr/bin/
 
+# Copy determine-reboot-cause service files
+sudo cp $IMAGE_CONFIGS/process-reboot-cause/determine-reboot-cause.service  $FILESYSTEM_ROOT/etc/systemd/system/
+sudo LANG=C chroot $FILESYSTEM_ROOT systemctl enable determine-reboot-cause.service
+sudo cp $IMAGE_CONFIGS/process-reboot-cause/determine-reboot-cause $FILESYSTEM_ROOT/usr/bin/
+
 ## Install package without starting service
 ## ref: https://wiki.debian.org/chroot
 sudo tee -a $FILESYSTEM_ROOT/usr/sbin/policy-rc.d > /dev/null <<EOF

files/build_templates/swss.service.j2

@@ -8,6 +8,7 @@ Requires=nps-modules-4.9.0-14-amd64.service
 {% endif %}
 After=database.service updategraph.service
 After=interfaces-config.service
+After=pmon.service
 Before=ntp-config.service
 StartLimitIntervalSec=1200
 StartLimitBurst=3

files/image_config/process-reboot-cause/determine-reboot-cause

@@ -0,0 +1,248 @@
+#!/usr/bin/env python
+#
+# determine-reboot-cause
+#
+# Program designed to run once, soon after system boot which will
+# determine the cause of the previous reboot and store it to the disk,
+#
+
+try:
+    import datetime
+    import json
+    import os
+    import pwd
+    import re
+    import sys
+    import syslog
+
+    import sonic_device_util
+except ImportError as err:
+    raise ImportError("%s - required module not found" % str(err))
+
+VERSION = "1.0"
+
+SYSLOG_IDENTIFIER = "determine-reboot-cause"
+
+REBOOT_CAUSE_DIR = "/host/reboot-cause/"
+REBOOT_CAUSE_FILE = REBOOT_CAUSE_DIR + "reboot-cause.txt"
+PREVIOUS_REBOOT_CAUSE_FILE = REBOOT_CAUSE_DIR + "previous-reboot-cause.txt"
+PREVIOUS_REBOOT_CAUSE_FILE_JSON = REBOOT_CAUSE_DIR + "previous-reboot-cause.json"
+FIRST_BOOT_PLATFORM_FILE = "/tmp/notify_firstboot_to_platform"
+REBOOT_TYPE_KEXEC_FILE = "/proc/cmdline"
+# The following SONIC_BOOT_TYPEs come from the warm/fast reboot script which is in sonic-utilities
+# Because the system can be rebooted from some old versions, we have to take all possible BOOT options into consideration.
+# On 201803, 201807 we have
+# BOOT_OPTIONS="$(echo $KERNEL_OPTIONS | sed -e 's/\s*linux\s*/BOOT_IMAGE=/') fast-reboot"
+# On 201811 and later we have
+# BOOT_OPTIONS="$(echo $KERNEL_OPTIONS | sed -e 's/\s*linux\s*/BOOT_IMAGE=/') SONIC_BOOT_TYPE=${BOOT_TYPE_ARG}" where BOOT_TYPE_ARG can be warm, fastfast or fast
+# To extract the commom part of them, we should have the following PATTERN
+REBOOT_TYPE_KEXEC_PATTERN_WARM = ".*SONIC_BOOT_TYPE=(warm|fastfast).*"
+REBOOT_TYPE_KEXEC_PATTERN_FAST = ".*SONIC_BOOT_TYPE=(fast|fast-reboot).*"
+
+REBOOT_CAUSE_UNKNOWN = "Unknown"
+
+
+# ========================== Syslog wrappers ==========================
+
+def log_info(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_INFO, msg)
+    syslog.closelog()
+
+
+def log_warning(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_WARNING, msg)
+    syslog.closelog()
+
+
+def log_error(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_ERR, msg)
+    syslog.closelog()
+
+
+# ============================= Functions =============================
+def parse_warmfast_reboot_from_proc_cmdline():
+    if os.path.isfile(REBOOT_TYPE_KEXEC_FILE):
+        with open(REBOOT_TYPE_KEXEC_FILE, "r") as cause_file:
+            cause_file_kexec = cause_file.readline()
+        m = re.search(REBOOT_TYPE_KEXEC_PATTERN_WARM, cause_file_kexec)
+        if m and m.group(1):
+            return 'warm-reboot'
+        m = re.search(REBOOT_TYPE_KEXEC_PATTERN_FAST, cause_file_kexec)
+        if m and m.group(1):
+            return 'fast-reboot'
+    return None
+
+
+def find_software_reboot_cause():
+    software_reboot_cause = REBOOT_CAUSE_UNKNOWN
+
+    if os.path.isfile(REBOOT_CAUSE_FILE):
+        with open(REBOOT_CAUSE_FILE, "r") as cause_file:
+            software_reboot_cause = cause_file.readline().rstrip('\n')
+            log_info("{} indicates the reboot cause: {}".format(REBOOT_CAUSE_FILE, software_reboot_cause))
+    else:
+        log_info("Reboot cause file {} not found".format(REBOOT_CAUSE_FILE))
+
+    if os.path.isfile(FIRST_BOOT_PLATFORM_FILE):
+        if software_reboot_cause == REBOOT_CAUSE_UNKNOWN:
+            version_info = sonic_device_util.get_sonic_version_info()
+            build_version = version_info['build_version'] if version_info else "unknown"
+            software_reboot_cause += " (First boot of SONiC version {})".format(build_version)
+        os.remove(FIRST_BOOT_PLATFORM_FILE)
+
+    return software_reboot_cause
+
+
+def find_proc_cmdline_reboot_cause():
+    proc_cmdline_reboot_cause = parse_warmfast_reboot_from_proc_cmdline()
+ 
+    if proc_cmdline_reboot_cause:
+        log_info("/proc/cmdline indicates reboot type: {}".format(proc_cmdline_reboot_cause))
+    else:
+        log_info("No reboot cause found from /proc/cmdline")
+ 
+    return proc_cmdline_reboot_cause
+ 
+
+def find_hardware_reboot_cause():
+    hardware_reboot_cause = None
+
+    # Until all platform vendors have provided sonic_platform packages,
+    # if there is no sonic_platform package installed, we only provide
+    # software-related reboot causes.
+    try:
+        import sonic_platform
+
+        platform = sonic_platform.platform.Platform()
+
+        chassis = platform.get_chassis()
+
+        hardware_reboot_cause_major, hardware_reboot_cause_minor = chassis.get_reboot_cause()
+
+        if hardware_reboot_cause_major == chassis.REBOOT_CAUSE_NON_HARDWARE:
+            # The reboot was not caused by hardware. If there is a REBOOT_CAUSE_FILE, it will
+            # contain any software-related reboot info. We will use it as the previous cause.
+            pass
+        elif hardware_reboot_cause_major == chassis.REBOOT_CAUSE_HARDWARE_OTHER:
+            hardware_reboot_cause = "{} ({})".format(hardware_reboot_cause_major, hardware_reboot_cause_minor)
+        else:
+            hardware_reboot_cause = hardware_reboot_cause_major
+    except ImportError as err:
+        log_warning("sonic_platform package not installed. Unable to detect hardware reboot causes.")
+
+    if hardware_reboot_cause:
+        log_info("Platform api indicates reboot cause {}".format(hardware_reboot_cause))
+    else:
+        log_info("No reboot cause found from platform api")
+
+    return hardware_reboot_cause
+
+
+def get_reboot_cause_dict(previous_reboot_cause, comment, gen_time):
+    """Store the key infomation of device reboot into a dictionary by parsing the string in
+    previous_reboot_cause.
+    If user issused a command to reboot device, then user, command and time will be
+    stored into a dictionary.
+    If device was rebooted due to the kernel panic, then the string `Kernel Panic`
+    and time will be stored into a dictionary.
+    """
+    reboot_cause_dict = {}
+    reboot_cause_dict['gen_time'] = gen_time
+    reboot_cause_dict['cause'] = previous_reboot_cause
+    reboot_cause_dict['user'] = "N/A"
+    reboot_cause_dict['time'] = "N/A"
+    reboot_cause_dict['comment'] = comment if comment is not None else "N/A"
+    if re.search(r'User issued', previous_reboot_cause):
+        # Match with "User issued '{}' command [User: {}, Time: {}]"
+        match = re.search(r'User issued \'(.*)\' command \[User: (.*), Time: (.*)\]', previous_reboot_cause)
+        if match is not None:
+            reboot_cause_dict['cause'] = match.group(1)
+            reboot_cause_dict['user'] = match.group(2)
+            reboot_cause_dict['time'] = match.group(3)
+    elif re.search(r'Kernel Panic', previous_reboot_cause):
+        match = re.search(r'Kernel Panic \[Time: (.*)\]', previous_reboot_cause)
+        if match is not None:
+            reboot_cause_dict['cause'] = "Kernel Panic"
+            reboot_cause_dict['time'] = match.group(1)
+
+    return reboot_cause_dict
+
+def main():
+    log_info("Starting up...")
+
+    if not os.geteuid() == 0:
+        log_error("User {} does not have permission to execute".format(pwd.getpwuid(os.getuid()).pw_name))
+        sys.exit("This utility must be run as root")
+
+    # Create REBOOT_CAUSE_DIR if it doesn't exist
+    if not os.path.exists(REBOOT_CAUSE_DIR):
+        os.makedirs(REBOOT_CAUSE_DIR)
+
+    # Remove stale PREVIOUS_REBOOT_CAUSE_FILE if it exists
+    if os.path.exists(PREVIOUS_REBOOT_CAUSE_FILE):
+        os.remove(PREVIOUS_REBOOT_CAUSE_FILE)
+
+    # Set a default previous reboot cause
+    previous_reboot_cause = REBOOT_CAUSE_UNKNOWN
+
+    # 1. Check if the previous reboot was warm/fast reboot by testing whether there is "fast|fastfast|warm" in /proc/cmdline
+    proc_cmdline_reboot_cause = find_proc_cmdline_reboot_cause()
+
+    # 2. Check if the previous reboot was caused by hardware
+    #    If yes, the hardware reboot cause will be treated as the reboot cause
+    hardware_reboot_cause = find_hardware_reboot_cause()
+
+    # 3. If there is a REBOOT_CAUSE_FILE, it will contain any software-related
+    #    reboot info. We will use it as the previous cause.
+    software_reboot_cause = find_software_reboot_cause()
+
+    additional_reboot_info = None
+
+    # The main decision logic of the reboot cause:
+    # If there is a reboot cause indicated by /proc/cmdline, it should be warmreboot/fastreboot
+    #   the software_reboot_cause which is the content of /hosts/reboot-cause/reboot-cause.txt 
+    #   will be treated as the reboot cause
+    # Elif there is a reboot cause indicated by platform API,
+    #   the hardware_reboot_cause will be treated as the reboot cause
+    # Else the software_reboot_cause will be treated as the reboot cause
+    if proc_cmdline_reboot_cause is not None:
+        previous_reboot_cause = software_reboot_cause
+        if not hardware_reboot_cause.startswith(REBOOT_CAUSE_NON_HARDWARE):
+            # Add the hardware_reboot_cause into additional_reboot_info
+            additional_reboot_info = hardware_reboot_cause
+    elif hardware_reboot_cause is not None:
+        previous_reboot_cause = hardware_reboot_cause
+        # Check if any software reboot was issued before this hardware reboot happened
+        if software_reboot_cause is not REBOOT_CAUSE_UNKNOWN:
+            additional_reboot_info = software_reboot_cause
+    else:
+        previous_reboot_cause = software_reboot_cause
+
+    # Current time
+    reboot_cause_gen_time = str(datetime.datetime.now().strftime('%Y_%m_%d_%H_%M_%S'))
+
+    # Save the previous cause info into its history file as json format
+    reboot_cause_dict = get_reboot_cause_dict(previous_reboot_cause, additional_reboot_info, reboot_cause_gen_time)
+
+    # Write the previous reboot cause to REBOOT_CAUSE_HISTORY_FILE_JSON as a JSON format
+    with open(PREVIOUS_REBOOT_CAUSE_FILE_JSON, "w") as reboot_cause_history_file:
+        json.dump(reboot_cause_dict, reboot_cause_history_file)
+
+    # Write the previous reboot cause to PREVIOUS_REBOOT_CAUSE_FILE
+    with open(PREVIOUS_REBOOT_CAUSE_FILE, "w") as prev_cause_file:
+        prev_cause_file.write(previous_reboot_cause)
+
+    # Remove the old REBOOT_CAUSE_FILE
+    if os.path.exists(REBOOT_CAUSE_FILE):
+        os.remove(REBOOT_CAUSE_FILE)
+
+    # Write a new default reboot cause file for the next reboot
+    with open(REBOOT_CAUSE_FILE, "w") as cause_file:
+        cause_file.write(REBOOT_CAUSE_UNKNOWN)
+
+
+if __name__ == "__main__":
+    main()

files/image_config/process-reboot-cause/determine-reboot-cause.service

@@ -0,0 +1,7 @@
+[Unit]
+Description=Reboot cause determination service
+After=rc-local.service
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/determine-reboot-cause

files/image_config/process-reboot-cause/process-reboot-cause

@@ -7,11 +7,12 @@
 #
 
 try:
+    import json
     import os
     import pwd
+    import re
     import sys
     import syslog
-    import re
 
     import sonic_device_util
 except ImportError as err:
@@ -22,19 +23,7 @@ VERSION = "1.0"
 SYSLOG_IDENTIFIER = "process-reboot-cause"
 
 REBOOT_CAUSE_DIR = "/host/reboot-cause/"
-REBOOT_CAUSE_FILE = REBOOT_CAUSE_DIR + "reboot-cause.txt"
+PREVIOUS_REBOOT_CAUSE_FILE = REBOOT_CAUSE_DIR + "previous-reboot-cause.json"
-PREVIOUS_REBOOT_CAUSE_FILE = REBOOT_CAUSE_DIR + "previous-reboot-cause.txt"
-FIRST_BOOT_PLATFORM_FILE = "/tmp/notify_firstboot_to_platform"
-REBOOT_TYPE_KEXEC_FILE = "/proc/cmdline"
-# The following SONIC_BOOT_TYPEs come from the warm/fast reboot script which is in sonic-utilities
-# Because the system can be rebooted from some old versions, we have to take all possible BOOT options into consideration.
-# On 201803, 201807 we have
-# BOOT_OPTIONS="$(echo $KERNEL_OPTIONS | sed -e 's/\s*linux\s*/BOOT_IMAGE=/') fast-reboot"
-# On 201811 and later we have
-# BOOT_OPTIONS="$(echo $KERNEL_OPTIONS | sed -e 's/\s*linux\s*/BOOT_IMAGE=/') SONIC_BOOT_TYPE=${BOOT_TYPE_ARG}" where BOOT_TYPE_ARG can be warm, fastfast or fast
-# To extract the commom part of them, we should have the following PATTERN
-REBOOT_TYPE_KEXEC_PATTERN_WARM = ".*SONIC_BOOT_TYPE=(warm|fastfast).*"
-REBOOT_TYPE_KEXEC_PATTERN_FAST = ".*SONIC_BOOT_TYPE=(fast|fast-reboot).*"
 
 REBOOT_CAUSE_UNKNOWN = "Unknown"
 
@@ -60,142 +49,27 @@ def log_error(msg):
 
 
 # ============================= Functions =============================
-def parse_warmfast_reboot_from_proc_cmdline():
-    if os.path.isfile(REBOOT_TYPE_KEXEC_FILE):
-        with open(REBOOT_TYPE_KEXEC_FILE, "r") as cause_file:
-            cause_file_kexec = cause_file.readline()
-        m = re.search(REBOOT_TYPE_KEXEC_PATTERN_WARM, cause_file_kexec)
-        if m and m.group(1):
-            return 'warm-reboot'
-        m = re.search(REBOOT_TYPE_KEXEC_PATTERN_FAST, cause_file_kexec)
-        if m and m.group(1):
-            return 'fast-reboot'
-    return None
-
-
-def find_software_reboot_cause():
-    software_reboot_cause = REBOOT_CAUSE_UNKNOWN
-
-    if os.path.isfile(REBOOT_CAUSE_FILE):
-        with open(REBOOT_CAUSE_FILE, "r") as cause_file:
-            software_reboot_cause = cause_file.readline().rstrip('\n')
-            log_info("{} indicates the reboot cause: {}".format(REBOOT_CAUSE_FILE, software_reboot_cause))
-    else:
-        log_info("Reboot cause file {} not found".format(REBOOT_CAUSE_FILE))
-
-    if os.path.isfile(FIRST_BOOT_PLATFORM_FILE):
-        if software_reboot_cause == REBOOT_CAUSE_UNKNOWN:
-            version_info = sonic_device_util.get_sonic_version_info()
-            build_version = version_info['build_version'] if version_info else "unknown"
-            software_reboot_cause += " (First boot of SONiC version {})".format(build_version)
-        os.remove(FIRST_BOOT_PLATFORM_FILE)
-
-    return software_reboot_cause
-
-
-def find_proc_cmdline_reboot_cause():
-    proc_cmdline_reboot_cause = parse_warmfast_reboot_from_proc_cmdline()
- 
-    if proc_cmdline_reboot_cause:
-        log_info("/proc/cmdline indicates reboot type: {}".format(proc_cmdline_reboot_cause))
-    else:
-        log_info("No reboot cause found from /proc/cmdline")
- 
-    return proc_cmdline_reboot_cause
- 
-
-def find_hardware_reboot_cause():
-    hardware_reboot_cause = None
-
-    # Until all platform vendors have provided sonic_platform packages,
-    # if there is no sonic_platform package installed, we only provide
-    # software-related reboot causes.
-    try:
-        import sonic_platform
-
-        platform = sonic_platform.platform.Platform()
-
-        chassis = platform.get_chassis()
-
-        hardware_reboot_cause_major, hardware_reboot_cause_minor = chassis.get_reboot_cause()
-
-        if hardware_reboot_cause_major == chassis.REBOOT_CAUSE_NON_HARDWARE:
-            # The reboot was not caused by hardware. If there is a REBOOT_CAUSE_FILE, it will
-            # contain any software-related reboot info. We will use it as the previous cause.
-            pass
-        elif hardware_reboot_cause_major == chassis.REBOOT_CAUSE_HARDWARE_OTHER:
-            hardware_reboot_cause = "{} ({})".format(hardware_reboot_cause_major, hardware_reboot_cause_minor)
-        else:
-            hardware_reboot_cause = hardware_reboot_cause_major
-    except ImportError as err:
-        log_warning("sonic_platform package not installed. Unable to detect hardware reboot causes.")
-
-    if hardware_reboot_cause:
-        log_info("Platform api indicates reboot cause {}".format(hardware_reboot_cause))
-    else:
-        log_info("No reboot cause found from platform api")
-
-    return hardware_reboot_cause
-
-
 def main():
-    log_info("Starting up...")
+    log_info("Logging reboot-cause...")
 
     if not os.geteuid() == 0:
         log_error("User {} does not have permission to execute".format(pwd.getpwuid(os.getuid()).pw_name))
         sys.exit("This utility must be run as root")
 
-    # Create REBOOT_CAUSE_DIR if it doesn't exist
-    if not os.path.exists(REBOOT_CAUSE_DIR):
-        os.makedirs(REBOOT_CAUSE_DIR)
-
-    # Remove stale PREVIOUS_REBOOT_CAUSE_FILE if it exists
-    if os.path.exists(PREVIOUS_REBOOT_CAUSE_FILE):
-        os.remove(PREVIOUS_REBOOT_CAUSE_FILE)
-
     # Set a default previous reboot cause
     previous_reboot_cause = REBOOT_CAUSE_UNKNOWN
 
-    # 1. Check if the previous reboot was warm/fast reboot by testing whether there is "fast|fastfast|warm" in /proc/cmdline
+    # Read the most recent reboot cause file and log data to syslog
-    proc_cmdline_reboot_cause = find_proc_cmdline_reboot_cause()
+    if os.path.exists(PREVIOUS_REBOOT_CAUSE_FILE):
+        with open(PREVIOUS_REBOOT_CAUSE_FILE, "r") as last_cause_file:
+            data = json.load(last_cause_file)
+            if data['user']:
+                previous_reboot_cause = USER_ISSUED_REBOOT_CAUSE_REGEX.format(data['cause'], data['user'], data['time'])
+            else:
+                previous_reboot_cause = "{}".format(data['cause'])
 
-    # 2. Check if the previous reboot was caused by hardware
+    # Log the last reboot cause to the syslog
-    #    If yes, the hardware reboot cause will be treated as the reboot cause
-    hardware_reboot_cause = find_hardware_reboot_cause()
-
-    # 3. If there is a REBOOT_CAUSE_FILE, it will contain any software-related
-    #    reboot info. We will use it as the previous cause.
-    software_reboot_cause = find_software_reboot_cause()
-
-    # The main decision logic of the reboot cause:
-    # If there is a reboot cause indicated by /proc/cmdline, it should be warmreboot/fastreboot
-    #   the software_reboot_cause which is the content of /hosts/reboot-cause/reboot-cause.txt 
-    #   will be treated as the reboot cause
-    # Elif there is a reboot cause indicated by platform API,
-    #   the hardware_reboot_cause will be treated as the reboot cause
-    # Else the software_reboot_cause will be treated as the reboot cause
-    if proc_cmdline_reboot_cause is not None:
-        previous_reboot_cause = software_reboot_cause
-    elif hardware_reboot_cause is not None:
-        previous_reboot_cause = hardware_reboot_cause
-    else:
-        previous_reboot_cause = software_reboot_cause
-
-    # Write the previous reboot cause to PREVIOUS_REBOOT_CAUSE_FILE
-    with open(PREVIOUS_REBOOT_CAUSE_FILE, "w") as prev_cause_file:
-        prev_cause_file.write(previous_reboot_cause)
-
-    # Also log the previous reboot cause to the syslog
     log_info("Previous reboot cause: {}".format(previous_reboot_cause))
 
-    # Remove the old REBOOT_CAUSE_FILE
-    if os.path.exists(REBOOT_CAUSE_FILE):
-        os.remove(REBOOT_CAUSE_FILE)
-
-    # Write a new default reboot cause file for the next reboot
-    with open(REBOOT_CAUSE_FILE, "w") as cause_file:
-        cause_file.write(REBOOT_CAUSE_UNKNOWN)
-
-
 if __name__ == "__main__":
     main()