[LLDP] Add lldpmgrd Daemon to Manage LLDP Configuration (#1428)

dockers/docker-lldp-sv2/Dockerfile.j2

@@ -1,37 +1,49 @@
 FROM docker-config-engine
 
-COPY \
-{% for deb in docker_lldp_sv2_debs.split(' ') -%}
-debs/{{ deb }}{{' '}}
-{%- endfor -%}
-debs/
+# Make apt-get non-interactive
+ENV DEBIAN_FRONTEND=noninteractive
 
-COPY python-wheels /python-wheels
+# Update apt's cache of available packages
+RUN apt-get update
 
-## Make apt-get non-interactive
-ENV DEBIAN_FRONTEND=noninteractive
+# Install dependencies
+RUN apt-get install -y python-pip libbsd0 libevent-2.0-5 libjansson4 libwrap0 libxml2 libpci3 libperl5.20 libpython2.7
+
+{% if docker_lldp_sv2_debs.strip() -%}
+# Copy locally-built Debian package dependencies
+{%- for deb in docker_lldp_sv2_debs.split(' ') %}
+COPY debs/{{ deb }} /debs/
+{%- endfor %}
 
-RUN apt-get update && apt-get install -y python-pip libbsd0 libevent-2.0-5 libjansson4 libwrap0 libxml2 libpci3 libperl5.20 
+# Install locally-built Debian packages and implicitly install their dependencies
+{%- for deb in docker_lldp_sv2_debs.split(' ') %}
+RUN dpkg_apt() { [ -f $1 ] && { dpkg -i $1 || apt-get -y install -f; } || return 1; }; dpkg_apt /debs/{{ deb }}
+{%- endfor %}
+{%- endif %}
 
-# Pre-install the fundamental packages
-# Install Python SwSS SDK
-# Install LLDP Sync Daemon
+{% if docker_lldp_sv2_whls.strip() -%}
+# Copy locally-built Python wheel dependencies
+{%- for whl in docker_lldp_sv2_whls.split(' ') %}
+COPY python-wheels/{{ whl }} /python-wheels/
+{%- endfor %}
 
-RUN dpkg -i \
-{% for deb in docker_lldp_sv2_debs.split(' ') -%}
-debs/{{ deb }}{{' '}}
+# Install locally-built Python wheel dependencies
+{%- for whl in docker_lldp_sv2_whls.split(' ') %}
+RUN pip install /python-wheels/{{ whl }}
 {%- endfor %}
+{% endif %}
 
-RUN pip install /python-wheels/swsssdk-2.0.1-py2-none-any.whl && \
-    pip install /python-wheels/sonic_d-2.0.0-py2-none-any.whl && \
-    apt-get remove -y python-pip && \
-    apt-get purge -y && apt-get autoclean -y && apt-get autoremove -y && \
-    rm -rf /debs /python-wheels ~/.cache
+# Clean up
+RUN apt-get remove -y python-pip
+RUN apt-get clean -y
+RUN apt-get autoclean -y
+RUN apt-get autoremove -y
+RUN rm -rf /debs /python-wheels ~/.cache
 
 COPY ["start.sh", "/usr/bin/"]
 COPY ["supervisord.conf", "/etc/supervisor/conf.d/"]
-COPY ["reconfigure.sh", "/usr/bin/"]
 COPY ["lldpd.conf.j2", "/usr/share/sonic/templates/"]
 COPY ["lldpd", "/etc/default/"]
+COPY ["lldpmgrd", "/usr/bin/"]
 
 ENTRYPOINT ["/usr/bin/supervisord"]

dockers/docker-lldp-sv2/lldpmgrd

@@ -0,0 +1,199 @@
+#!/usr/bin/env python
+
+"""
+    lldpmgrd
+
+    LLDP manager daemon for SONiC
+
+    Daemon which listens for changes in the PORT table of the State DB
+    and updates LLDP configuration accordingly for that port by calling
+    lldpcli.
+
+    TODO: Also listen for changes in DEVICE_NEIGHBOR and PORT tables in
+          Config DB and update LLDP config upon changes.
+"""
+
+
+try:
+    import os
+    import signal
+    import subprocess
+    import sys
+    import syslog
+    from swsscommon import swsscommon
+except ImportError as err:
+    raise ImportError("%s - required module not found" % str(err))
+
+VERSION = "1.0"
+
+SYSLOG_IDENTIFIER = "lldpmgrd"
+
+
+# ========================== 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()
+
+
+# ========================== Signal Handling ==========================
+
+def signal_handler(sig, frame):
+    if sig == signal.SIGHUP:
+        log_info("Caught SIGHUP - ignoring...")
+        return
+    elif sig == signal.SIGINT:
+        log_info("Caught SIGINT - exiting...")
+        sys.exit(128 + sig)
+    elif sig == signal.SIGTERM:
+        log_info("Caught SIGTERM - exiting...")
+        sys.exit(128 + sig)
+    else:
+        log_warning("Caught unhandled signal '" + sig + "'")
+
+
+# ============================== Classes ==============================
+
+class LldpManager(object):
+    """
+    Class which subscribes to notifications of changes in the PORT table of
+    the Redis State database and updates LLDP configuration accordingly for
+    that port by calling lldpcli.
+    Attributes:
+        state_db: Handle to Redis State database via swsscommon lib
+        config_db: Handle to Redis Config database via swsscommon lib
+    """
+    REDIS_HOSTNAME = "localhost"
+    REDIS_PORT = 6379
+    REDIS_TIMEOUT_USECS = 0
+
+    def __init__(self):
+        # Open a handle to the State database
+        self.state_db = swsscommon.DBConnector(swsscommon.STATE_DB,
+                                               self.REDIS_HOSTNAME,
+                                               self.REDIS_PORT,
+                                               self.REDIS_TIMEOUT_USECS)
+
+        # Open a handle to the Config database
+        self.config_db = swsscommon.DBConnector(swsscommon.CONFIG_DB,
+                                                self.REDIS_HOSTNAME,
+                                                self.REDIS_PORT,
+                                                self.REDIS_TIMEOUT_USECS)
+
+    def update_lldp_config_for_port(self, port_name):
+        """
+        For port `port_name`, look up the neighboring device's hostname and
+        corresponding port alias in the Config database, then form the
+        appropriate lldpcli configuration command and run it.
+        """
+        TABLE_SEPARATOR = "|"
+
+        # Retrieve all entires for this port from the Port table
+        port_table = swsscommon.Table(self.config_db, swsscommon.CFG_PORT_TABLE_NAME, TABLE_SEPARATOR)
+        (status, fvp) = port_table.get(port_name)
+        if status:
+            # Convert list of tuples to a dictionary
+            port_table_dict = dict(fvp)
+
+            # Get the port alias. If None or empty string, use port name instead
+            port_alias = port_table_dict.get("alias")
+            if not port_alias:
+                log_info("Unable to retrieve port alias for port '{}'. Using port name instead.".format(port_name))
+                port_alias = port_name
+        else:
+            log_error("Port '{}' not found in {} table in Config DB. Using port name instead of port alias.".format(port_name, swsscommon.CFG_PORT_TABLE_NAME))
+            port_alias = port_name
+
+        lldpcli_cmd = "lldpcli configure ports {0} lldp portidsubtype local {1}".format(port_name, port_alias)
+
+        # Retrieve all entires for this port from the Device Neighbor table
+        device_neighbor_table = swsscommon.Table(self.config_db, swsscommon.CFG_DEVICE_NEIGHBOR_TABLE_NAME, TABLE_SEPARATOR)
+        (status, fvp) = device_neighbor_table.get(port_name)
+        if status:
+            # Convert list of tuples to a dictionary
+            device_neighbor_table_dict = dict(fvp)
+
+            # Get neighbor host name and port name
+            neighbor_hostname = device_neighbor_table_dict.get("name")
+            neighbor_portname = device_neighbor_table_dict.get("port")
+
+            # If we sucessfully obtained the neighbor's host name and port name, append a port description to the command
+            if neighbor_hostname and neighbor_portname:
+                lldpcli_cmd += " description {0}:{1}".format(neighbor_hostname, neighbor_portname)
+            else:
+                if not neighbor_hostname:
+                    log_info("Failed to retrieve neighbor host name for port '{}'. Not adding port description.".format(port_name))
+
+                if not neighbor_portname:
+                    log_info("Failed to retrieve neighbor port name for port '{}'. Not adding port description.".format(port_name))
+        else:
+            log_info("Unable to retrieve neighbor information for port '{}'. Not adding port description.".format(port_name))
+
+        log_info("Running command: '{}'".format(lldpcli_cmd))
+
+        proc = subprocess.Popen(lldpcli_cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+
+        (stdout, stderr) = proc.communicate()
+
+        if proc.returncode != 0:
+            log_error("Error running command '{}': {}".format(cmd, stderr))
+
+    def run(self):
+        """
+        Infinite loop. Subscribes to notifications of changes in the PORT table
+        of the Redis State database. When we are notified of the creation of an
+        interface, update LLDP configuration accordingly.
+        """
+        # Subscribe to PORT table notifications in the State DB
+        sel = swsscommon.Select()
+        sst = swsscommon.SubscriberStateTable(self.state_db, swsscommon.STATE_PORT_TABLE_NAME)
+        sel.addSelectable(sst)
+
+        # Listen indefinitely for changes to the PORT table in the State DB
+        while True:
+            (state, c, fd) = sel.select()
+            if state != swsscommon.Select.OBJECT:
+                log_warning("sel.select() did not return swsscommon.Select.OBJECT")
+                continue
+
+            (key, op, fvp) = sst.pop()
+            fvp_dict = dict(fvp)
+
+            if op == "SET" and fvp_dict.get("state") == "ok":
+                self.update_lldp_config_for_port(key)
+
+
+# ============================= Functions =============================
+
+def main():
+    log_info("Starting up...")
+
+    if not os.geteuid() == 0:
+        log_error("Must be root to run this daemon")
+        print "Error: Must be root to run this daemon"
+        sys.exit(1)
+
+    # Register our signal handlers
+    signal.signal(signal.SIGHUP, signal_handler)
+    signal.signal(signal.SIGINT, signal_handler)
+    signal.signal(signal.SIGTERM, signal_handler)
+
+    # Instantiate a LldpManager object
+    lldpmgr = LldpManager()
+    lldpmgr.run()
+
+if __name__ == "__main__":
+    main()

dockers/docker-lldp-sv2/start.sh

@@ -9,5 +9,5 @@ rm -f /var/run/rsyslogd.pid
 
 supervisorctl start rsyslogd
 supervisorctl start lldpd
-supervisorctl start lldpd-conf-reload
 supervisorctl start lldp-syncd
+supervisorctl start lldpmgrd

dockers/docker-lldp-sv2/supervisord.conf

@@ -26,23 +26,23 @@ stderr_logfile=syslog
 # - `-ddd` means to stay in foreground, log warnings and info to console
 # - `-dddd` means to stay in foreground, log all to console
 command=/usr/sbin/lldpd -d -I Ethernet*,eth*
-priority=100
+priority=3
 autostart=false
 autorestart=false
 stdout_logfile=syslog
 stderr_logfile=syslog
 
-[program:lldpd-conf-reload]
-command=/usr/bin/reconfigure.sh
-priority=150
+[program:lldp-syncd]
+command=/usr/bin/env python2 -m lldp_syncd
+priority=4
 autostart=false
 autorestart=false
 stdout_logfile=syslog
 stderr_logfile=syslog
 
-[program:lldp-syncd]
-command=/usr/bin/env python2 -m lldp_syncd
-priority=200
+[program:lldpmgrd]
+command=/usr/bin/lldpmgrd
+priority=5
 autostart=false
 autorestart=false
 stdout_logfile=syslog

rules/docker-lldp-sv2.mk

@@ -2,7 +2,7 @@
 
 DOCKER_LLDP_SV2 = docker-lldp-sv2.gz
 $(DOCKER_LLDP_SV2)_PATH = $(DOCKERS_PATH)/docker-lldp-sv2
-$(DOCKER_LLDP_SV2)_DEPENDS += $(LLDPD)
+$(DOCKER_LLDP_SV2)_DEPENDS += $(LLDPD) $(LIBSWSSCOMMON) $(PYTHON_SWSSCOMMON)
 $(DOCKER_LLDP_SV2)_PYTHON_WHEELS += $(DBSYNCD_PY2)
 $(DOCKER_LLDP_SV2)_LOAD_DOCKERS += $(DOCKER_CONFIG_ENGINE)
 SONIC_DOCKER_IMAGES += $(DOCKER_LLDP_SV2)