Generic changes and new py-common API's for BMC based platforms

device/nexthop/arm64-nexthop_b27-r0/pmon_daemon_control.json

@@ -1,13 +1,17 @@
 {
-    "skip_thermalctld": false,
+    "skip_chassisd": true,
     "skip_ledd": true,
     "skip_xcvrd": true,
     "skip_psud": true,
-    "skip_syseepromd": true,
-    "skip_pcied": true,
-    "skip_chassisd": true,
+    "skip_syseepromd": false,
+    "skip_thermalctld": false,
     "skip_fancontrol": true,
+    "skip_sensors": true,
+    "skip_pcied": true,
+    "skip_stormond": false,
+    "skip_ycabled": true,
     "include_sensormond": false,
+    "skip_chassis_db_init": false,
     "thermalctld": {
         "thermal_monitor_initial_interval": 5,
         "thermal_monitor_update_interval": 60,

dockers/docker-database/database_config.json.j2

@@ -24,7 +24,7 @@
             "persistence_for_warm_boot" : "yes"
         }
 {% endif %}
-{% if DATABASE_TYPE is defined and (DATABASE_TYPE == "dpudb" or DATABASE_TYPE == "bmcdb") %}
+{% if DATABASE_TYPE is defined and DATABASE_TYPE == "dpudb" %}
 {% else %}
         ,
         "redis_bmp":{
@@ -139,8 +139,6 @@
             "separator": ":",
             "instance" : {% if include_remote_db %} "remote_redis" {% else %} "redis" {% endif %}
         }
-{% elif DATABASE_TYPE is defined and DATABASE_TYPE == "bmcdb" %}
-        {# No BMP_STATE_DB for BMC devices #}
 {% else %}
         ,
         "BMP_STATE_DB" : {

dockers/docker-database/docker-database-init.sh

@@ -41,10 +41,6 @@ then
     fi
 fi
 
-if [[ $IS_BMC_DEVICE == "true" ]]
-then
-    export DATABASE_TYPE="bmcdb"
-fi
 
 export BMP_DB_PORT=6400
 

dockers/docker-database/multi_database_config.json.j2

@@ -60,7 +60,7 @@
             "persistence_for_warm_boot" : "yes"
         }
 {% endif %}
-{% if DATABASE_TYPE is defined and (DATABASE_TYPE == "dpudb" or DATABASE_TYPE == "bmcdb") %}
+{% if DATABASE_TYPE is defined and DATABASE_TYPE == "dpudb" %}
 {% else %}
         ,
         "redis_bmp":{
@@ -185,8 +185,6 @@
             "separator": ":",
             "instance" : {% if include_remote_db %} "remote_redis" {% else %} "redis" {% endif %}
         }
-{% elif DATABASE_TYPE is defined and DATABASE_TYPE == "bmcdb" %}
-        {# No BMP_STATE_DB for BMC devices #}
 {% else %}
         ,
         "BMP_STATE_DB" : {

dockers/docker-platform-monitor/docker-pmon.supervisord.conf.j2

@@ -31,6 +31,23 @@ stderr_syslog=true
 dependent_startup=true
 
 
+{% if IS_SWITCH_BMC %}
+[program:bmcctld]
+command=/usr/local/bin/bmcctld
+priority=2
+autostart=false
+autorestart=unexpected
+stdout_logfile=NONE
+stdout_syslog=true
+stderr_logfile=NONE
+stderr_syslog=true
+startsecs=10
+startretries=50
+dependent_startup=true
+dependent_startup_wait_for=rsyslogd:running
+{% endif %}
+
+
 {% if delay_non_critical_daemon %}
 [program:delay]
 command=python3 /usr/bin/delay.py
@@ -40,7 +57,7 @@ startsecs=0
 dependent_startup=true
 {% endif %}
 
-{% if not skip_chassisd and (IS_MODULAR_CHASSIS == 1 or is_smartswitch) %}
+{% if not skip_chassisd and (IS_MODULAR_CHASSIS == 1 or is_smartswitch) and not IS_SWITCH_BMC %}
 [program:chassisd]
 command=/usr/local/bin/chassisd
 priority=3

dockers/docker-platform-monitor/docker_init.j2

@@ -140,7 +140,17 @@ if [ -e $MODULAR_CHASSISDB_CONF_FILE ] && [[ $disaggregated_chassis -ne 1 ]]; th
     IS_MODULAR_CHASSIS=1
 fi
 
-confvar="{\"HAVE_SENSORS_CONF\":$HAVE_SENSORS_CONF, \"HAVE_FANCONTROL_CONF\":$HAVE_FANCONTROL_CONF, \"API_VERSION\":$SONIC_PLATFORM_API_PYTHON_VERSION, \"IS_MODULAR_CHASSIS\":$IS_MODULAR_CHASSIS}"
+# Determine if this pmon instance is running on the Switch BMC.
+# switch_bmc=1 is set in platform_env.conf on BMC systems.
+IS_SWITCH_BMC=0
+if [ -e $PLATFORM_ENV_CONF_FILE ]; then
+    bmc_val=$(grep -s '^switch_bmc=' $PLATFORM_ENV_CONF_FILE | cut -d= -f2 | tr -d '[:space:]')
+    if [[ "$bmc_val" == "1" ]]; then
+        IS_SWITCH_BMC=1
+    fi
+fi
+
+confvar="{\"HAVE_SENSORS_CONF\":$HAVE_SENSORS_CONF, \"HAVE_FANCONTROL_CONF\":$HAVE_FANCONTROL_CONF, \"API_VERSION\":$SONIC_PLATFORM_API_PYTHON_VERSION, \"IS_MODULAR_CHASSIS\":$IS_MODULAR_CHASSIS, \"IS_SWITCH_BMC\":$IS_SWITCH_BMC}"
 
 if [ -e $PMON_DAEMON_CONTROL_FILE ];
 then

files/build_templates/docker_image_ctl.j2

@@ -111,9 +111,7 @@ function preStartAction()
             # Create an emtpy file and overwrite any RDB if already there
             echo -n > /tmp/dump.rdb
             docker cp /tmp/dump.rdb database$DEV:/var/lib/redis/
-            if [[ "$DATABASE_TYPE" != "bmcdb" ]]; then
-                docker cp /tmp/dump.rdb database$DEV:/var/lib/redis_bmp/
-            fi
+            docker cp /tmp/dump.rdb database$DEV:/var/lib/redis_bmp/
         fi
     fi
 {%- elif docker_container_name == "pde" %}
@@ -433,6 +431,17 @@ start() {
         source $PLATFORM_ENV_CONF
     fi
 
+    # switch_host=1 / switch_bmc=1 may be set by platform_env.conf above.
+    # Normalise to 0 when absent so downstream env vars are always defined.
+    IS_SWITCH_HOST=${switch_host:-0}
+    IS_SWITCH_BMC=${switch_bmc:-0}
+
+    # Derive IS_BMC_DEVICE from switch_bmc so docker-database-init.sh can use
+    # the existing IS_BMC_DEVICE mechanism without extra env vars.
+    if [[ "$IS_SWITCH_BMC" == "1" ]]; then
+        IS_BMC_DEVICE=true
+    fi
+
 
     {%- if sonic_asic_platform == "broadcom" %}
     {%- if docker_container_name == "syncd" %}
@@ -889,10 +898,6 @@ if [[ "$DEV" == *"dpu"* ]]; then
     DATABASE_TYPE="dpudb"
 fi
 
-if [[ "$IS_BMC_DEVICE" == "true" ]]; then
-    DATABASE_TYPE="bmcdb"
-fi
-
 {%- endif %}
 NAMESPACE_PREFIX="asic"
 DOCKERNAME=$DOCKERNAME$DEV

files/image_config/constants/bmc.json

@@ -0,0 +1,6 @@
+{
+    "bmc_if_name": "bmc0",
+    "bmc_if_addr": "169.254.100.2",
+    "bmc_addr": "169.254.100.1",
+    "bmc_net_mask": "255.255.255.252"
+}

files/image_config/logrotate/logrotate.d/bmc-event

@@ -0,0 +1,13 @@
+# BMC persistent event log: leak events, Switch-Host power state changes,
+# and Rack Manager interactions.  Lives on /host (eMMC) so it survives
+# reboots and tmpfs-mounted /var/log.
+/host/bmc/event.log {
+    missingok
+    notifempty
+    size 10M
+    rotate 5
+    compress
+    delaycompress
+    copytruncate
+    create 0640 root root
+}

files/image_config/platform/rc.local

@@ -425,4 +425,14 @@ if [ -f /var/log/fsck.log.gz ]; then
     rm -f /var/log/fsck.log.gz
 fi
 
+# On Switch-BMC systems, create the persistent BMC event log directory and
+# file on /host (eMMC-backed) so that leak, power and host-state events
+# survive reboots.  /var/log is on tmpfs so it is NOT used for this.
+PLATFORM_ENV_CONF="/usr/share/sonic/device/$platform/platform_env.conf"
+if [ -f "$PLATFORM_ENV_CONF" ] && grep -q '^switch_bmc=1' "$PLATFORM_ENV_CONF" 2>/dev/null; then
+    mkdir -p /host/bmc
+    touch /host/bmc/event.log
+    chmod 640 /host/bmc/event.log
+fi
+
 exit 0

files/initramfs-tools/union-mount.j2

@@ -54,6 +54,15 @@ for x in $(cat /proc/cmdline); do
     esac
 done
 
+# On Switch-BMC systems /var/log is always on tmpfs to avoid wearing out
+# the eMMC flash with high-frequency syslog writes.
+_platform=$(grep '^onie_platform=' ${rootmnt}/host/machine.conf 2>/dev/null | cut -d= -f2)
+_penv="${rootmnt}/usr/share/sonic/device/${_platform}/platform_env.conf"
+if [ -f "$_penv" ] && grep -q '^switch_bmc=1' "$_penv" 2>/dev/null; then
+    logs_inram=true
+fi
+unset _platform _penv
+
 set_tmpfs_log_partition_size()
 {
     if [ $varlog_size -gt 0 ]; then

src/sonic-py-common/sonic_py_common/daemon_base.py

@@ -29,6 +29,23 @@ def db_connect(db_name, namespace=EMPTY_NAMESPACE):
     return swsscommon.DBConnector(db_name, REDIS_TIMEOUT_MSECS, True, namespace)
 
 
+def db_connect_remote(db_id, host, port=6379):
+    """
+    Connect to a Redis instance on a remote host by IP and port,
+    bypassing database_config.json lookup entirely.
+
+    Args:
+        db_id: Redis database index (e.g. 6 for STATE_DB, 4 for CONFIG_DB)
+        host : IP address of the remote Redis
+        port : TCP port of the remote Redis (default 6379)
+
+    Returns:
+        A swsscommon.DBConnector connected to the remote instance.
+    """
+    from swsscommon import swsscommon
+    return swsscommon.DBConnector(db_id, host, port, REDIS_TIMEOUT_MSECS)
+
+
 #
 # DaemonBase ===================================================================
 #

src/sonic-py-common/sonic_py_common/device_info.py

@@ -23,6 +23,7 @@
 PLATFORM_JSON_FILE = "platform.json"
 BMC_DATA_FILE = 'bmc.json'
 BMC_BUILD_CONFIG_FILE = '/etc/sonic/bmc_config.json'
+GLOBAL_BMC_DATA_FILE = '/etc/sonic/bmc.json'
 
 # Fabric port configuration file names
 FABRIC_MONITOR_CONFIG_FILE = "fabric_monitor_config.json"
@@ -693,6 +694,81 @@ def is_dpu():
     return False
 
 
+def is_switch_host():
+    """
+    Check if this system is the Switch-Host (the main switching ASIC host,
+    as opposed to the Switch BMC).  Reads the 'switch_host' key from
+    platform_env.conf.
+
+    Returns:
+        True if switch_host=1 is present in platform_env.conf, False otherwise.
+    """
+    platform_env_conf_file_path = get_platform_env_conf_file_path()
+    if platform_env_conf_file_path is None:
+        return False
+    with open(platform_env_conf_file_path) as platform_env_conf_file:
+        for line in platform_env_conf_file:
+            tokens = line.split('=')
+            if len(tokens) < 2:
+                continue
+            if tokens[0].lower() == 'switch_host':
+                return tokens[1].strip() == '1'
+    return False
+
+
+def is_switch_bmc():
+    """
+    Check if this system is the Switch BMC (the Baseboard Management
+    Controller running SONiC).  Reads the 'switch_bmc' key from
+    platform_env.conf.
+
+    Returns:
+        True if switch_bmc=1 is present in platform_env.conf, False otherwise.
+    """
+    platform_env_conf_file_path = get_platform_env_conf_file_path()
+    if platform_env_conf_file_path is None:
+        return False
+    with open(platform_env_conf_file_path) as platform_env_conf_file:
+        for line in platform_env_conf_file:
+            tokens = line.split('=')
+            if len(tokens) < 2:
+                continue
+            if tokens[0].lower() == 'switch_bmc':
+                return tokens[1].strip() == '1'
+    return False
+
+
+def is_liquid_cooled():
+    """
+    Check if this system uses liquid (or hybrid) cooling.  Reads the
+    'liquid_cooled' key from platform_env.conf.
+
+    Returns:
+        True if liquid_cooled=true is present in platform_env.conf, False otherwise.
+    """
+    platform_env_conf_file_path = get_platform_env_conf_file_path()
+    if platform_env_conf_file_path is None:
+        return False
+    with open(platform_env_conf_file_path) as platform_env_conf_file:
+        for line in platform_env_conf_file:
+            tokens = line.split('=')
+            if len(tokens) < 2:
+                continue
+            if tokens[0].lower() == 'liquid_cooled':
+                return tokens[1].strip().lower() == 'true'
+    return False
+
+
+def is_air_cooled():
+    """
+    Check if this system uses air cooling (i.e., is NOT liquid cooled).
+
+    Returns:
+        True when the system is not liquid cooled, False otherwise.
+    """
+    return not is_liquid_cooled()
+
+
 def is_supervisor():
     platform_env_conf_file_path = get_platform_env_conf_file_path()
     if platform_env_conf_file_path is None:
@@ -982,18 +1058,66 @@ def is_warm_restart_enabled(container_name):
 
 
 def get_bmc_data():
-    json_file = None
+    """
+    Get BMC network configuration.
+
+    Checks the SONiC-wide global bmc.json (/etc/sonic/bmc.json) first; if
+    that file is absent, falls back to the platform-specific bmc.json in
+    the platform directory.  A platform bmc.json overrides the global file
+    when both are present in the sense that sonic-config-engine will copy
+    the platform file over the installed global one during image generation.
+
+    Returns:
+        A dict with bmc_if_name, bmc_if_addr, bmc_addr and bmc_net_mask,
+        or None if no bmc.json is found.
+    """
     try:
-        platform_path = get_path_to_platform_dir()
-        json_file = os.path.join(platform_path, BMC_DATA_FILE)
-        if os.path.exists(json_file):
-            with open(json_file, "r") as f:
+        if os.path.exists(GLOBAL_BMC_DATA_FILE):
+            with open(GLOBAL_BMC_DATA_FILE, "r") as f:
                 return json.load(f)
+        platform_path = get_path_to_platform_dir()
+        if platform_path:
+            json_file = os.path.join(platform_path, BMC_DATA_FILE)
+            if os.path.exists(json_file):
+                with open(json_file, "r") as f:
+                    return json.load(f)
         return None
     except Exception:
         return None
 
 
+def get_bmc_address():
+    """
+    Return the IP address of the BMC.
+
+    Reads 'bmc_addr' from bmc.json (/etc/sonic/bmc.json or platform bmc.json).
+    Use this on a Switch-Host to connect to the BMC's Redis over TCP.
+
+    Returns:
+        IP address string, or None if bmc.json is unavailable.
+    """
+    bmc_data = get_bmc_data()
+    if not bmc_data:
+        return None
+    return bmc_data.get('bmc_addr')
+
+
+def get_switch_host_address():
+    """
+    Return the IP address of the switch-host's BMC interface.
+
+    Reads 'bmc_if_addr' from bmc.json (/etc/sonic/bmc.json or platform bmc.json).
+    Use this on a Switch-BMC to connect to the switch-host's Redis over TCP.
+
+    Returns:
+        IP address string, or None if bmc.json is unavailable.
+    """
+    bmc_data = get_bmc_data()
+    if not bmc_data:
+        return None
+    return bmc_data.get('bmc_if_addr')
+
+
 def get_bmc_build_config():
     """
     Get BMC build-time configuration