[dhcp_relay] Use dhcprelayd to manage critical processes (#17236)

Modify j2 template files in docker-dhcp-relay. Add dhcprelayd to group dhcp-relay instead of isc-dhcp-relay-VlanXXX, which would make dhcprelayd to become critical process. In dhcprelayd, subscribe FEATURE table to check whether dhcp_server feature is enabled. 2.1 If dhcp_server feature is disabled, means we need original dhcp_relay functionality, dhcprelayd would do nothing. Because dhcrelay/dhcpmon configuration is generated in supervisord configuration, they will automatically run. 2.2 If dhcp_server feature is enabled, dhcprelayd will stop dhcpmon/dhcrelay processes started by supervisord and subscribe dhcp_server related tables in config_db to start dhcpmon/dhcrelay processes. 2.3 While dhcprelayd running, it will regularly check feature status (by default per 5s) and would encounter below 4 state change about dhcp_server feature: A) disabled -> enabled In this scenario, dhcprelayd will subscribe dhcp_server related tables and stop dhcpmon/dhcrelay processes started by supervisord and start new pair of dhcpmon/dhcrelay processes. After this, dhcpmon/dhcrelay processes are totally managed by dhcprelayd. B) enabled -> enabled In this scenaro, dhcprelayd will monitor db changes in dhcp_server related tables to determine whether to restart dhcpmon/dhrelay processes. C) enabled -> disabled In this scenario, dhcprelayd would unsubscribe dhcp_server related tables and kill dhcpmon/dhcrelay processes started by itself. And then dhcprelayd will start dhcpmon/dhcrelay processes via supervisorctl. D) disabled -> disabled dhcprelayd will check whether dhcrelay processes running status consistent with supervisord configuration file. If they are not consistent, dhcprelayd will kill itself, then dhcp_relay container will stop because dhcprelayd is critical process.
sonic-net · Nov 27, 2023 · da80593 · da80593
1 parent 49dd425
commit da80593
Show file tree

Hide file tree

Showing 21 changed files with 506 additions and 119 deletions.
diff --git a/dockers/docker-dhcp-relay/Dockerfile.j2 b/dockers/docker-dhcp-relay/Dockerfile.j2
@@ -13,13 +13,11 @@ ENV IMAGE_VERSION=$image_version
 # Update apt's cache of available packages
 RUN apt-get update
 
-RUN apt-get install -y libjsoncpp-dev {%- if INCLUDE_DHCP_SERVER == "y" %}\
-                       python3-dev         \
-                       build-essential{%- endif %}
+RUN apt-get install -y libjsoncpp-dev \
+                       python3-dev    \
+                       build-essential
 
-{% if INCLUDE_DHCP_SERVER == "y" -%}
 RUN pip3 install psutil
-{%- endif %}
 
 RUN apt-get install -y libjsoncpp-dev
 
@@ -40,10 +38,8 @@ RUN apt-get install -y libjsoncpp-dev
 {% endif %}
 
 # Clean up
-{% if INCLUDE_DHCP_SERVER == "y" -%}
 RUN apt-get remove -y build-essential     \
                 python3-dev
-{%- endif %}
 RUN apt-get clean -y         && \
     apt-get autoclean -y     && \
     apt-get autoremove -y    && \

diff --git a/dockers/docker-dhcp-relay/dhcp-relay.programs.j2 b/dockers/docker-dhcp-relay/dhcp-relay.programs.j2
@@ -1,18 +1,10 @@
 [group:dhcp-relay]
-programs=
+programs=dhcprelayd,
 {%- set relay_for_ipv6 = { 'flag': False } %}
 {%- set add_preceding_comma = { 'flag': False } %}
 {% if dhcp_server_ipv4_enabled %}
-{% set _dummy = add_preceding_comma.update({'flag': True}) %}
-dhcprelayd
 {%- endif %}
 {% for vlan_name in VLAN_INTERFACE %}
-{# Append DHCPv4 agents #}
-{% if not dhcp_server_ipv4_enabled and VLAN and vlan_name in VLAN and 'dhcp_servers' in VLAN[vlan_name] and VLAN[vlan_name]['dhcp_servers']|length > 0 %}
-{% if add_preceding_comma.flag %},{% endif %}
-{% set _dummy = add_preceding_comma.update({'flag': True}) %}
-isc-dhcpv4-relay-{{ vlan_name }}
-{%- endif %}
 {% if DHCP_RELAY and vlan_name in DHCP_RELAY and DHCP_RELAY[vlan_name]['dhcpv6_servers']|length > 0 %}
 {% set _dummy = relay_for_ipv6.update({'flag': True})  %}
 {%- endif %}

diff --git a/dockers/docker-dhcp-relay/docker-dhcp-relay.supervisord.conf.j2 b/dockers/docker-dhcp-relay/docker-dhcp-relay.supervisord.conf.j2
@@ -39,10 +39,6 @@ stderr_logfile=syslog
 dependent_startup=true
 dependent_startup_wait_for=rsyslogd:running
 
-{% set dhcp_server_ipv4_enabled = False %}
-{% if FEATURE and 'dhcp_server' in FEATURE and 'state' in FEATURE['dhcp_server'] and FEATURE['dhcp_server']['state'] == 'enabled' %}
-{% set dhcp_server_ipv4_enabled = True %}
-{% endif %}
 {# If our configuration has VLANs... #}
 {% if VLAN_INTERFACE %}
 {# Count how many VLANs require a DHCP relay agent... #}
@@ -63,16 +59,14 @@ dependent_startup_wait_for=rsyslogd:running
 {# Create a program entry for each DHCP relay agent instance #}
 {% set relay_for_ipv4 = { 'flag': False } %}
 {% set relay_for_ipv6 = { 'flag': False } %}
-{% if not dhcp_server_ipv4_enabled %}
 {% for vlan_name in VLAN_INTERFACE %}
 {% include 'dhcpv4-relay.agents.j2' %}
 {% endfor %}
 
-{% endif %}
 {% include 'dhcpv6-relay.agents.j2' %}
-{% if not dhcp_server_ipv4_enabled %}
 {% include 'dhcp-relay.monitors.j2' %}
-{% else %}
+{% endif %}
+{% endif %}
 [program:dhcprelayd]
 command=/usr/local/bin/dhcprelayd
 priority=3
@@ -82,6 +76,3 @@ stdout_logfile=syslog
 stderr_logfile=syslog
 dependent_startup=true
 dependent_startup_wait_for=start:exited
-{% endif %}
-{% endif %}
-{% endif %}
diff --git a/rules/docker-dhcp-relay.mk b/rules/docker-dhcp-relay.mk
@@ -17,9 +17,7 @@ $(DOCKER_DHCP_RELAY)_LOAD_DOCKERS = $(DOCKER_CONFIG_ENGINE_BULLSEYE)
 
 $(DOCKER_DHCP_RELAY)_INSTALL_PYTHON_WHEELS = $(SONIC_UTILITIES_PY3)
 $(DOCKER_DHCP_RELAY)_INSTALL_DEBS = $(PYTHON3_SWSSCOMMON)
-ifeq ($(INCLUDE_DHCP_SERVER), y)
 $(DOCKER_DHCP_RELAY)_PYTHON_WHEELS += $(SONIC_DHCP_SERVER_PY3)
-endif
 
 $(DOCKER_DHCP_RELAY)_VERSION = 1.0.0
 $(DOCKER_DHCP_RELAY)_PACKAGE_NAME = dhcp-relay

diff --git a/rules/sonic-dhcp-server.mk b/rules/sonic-dhcp-server.mk
@@ -5,6 +5,4 @@ $(SONIC_DHCP_SERVER_PY3)_SRC_PATH = $(SRC_PATH)/sonic-dhcp-server
 $(SONIC_DHCP_SERVER_PY3)_DEPENDS += $(SONIC_PY_COMMON_PY3)
 $(SONIC_DHCP_SERVER_PY3)_DEBS_DEPENDS = $(LIBSWSSCOMMON) $(PYTHON3_SWSSCOMMON)
 $(SONIC_DHCP_SERVER_PY3)_PYTHON_VERSION = 3
-ifeq ($(INCLUDE_DHCP_SERVER), y)
 SONIC_PYTHON_WHEELS += $(SONIC_DHCP_SERVER_PY3)
-endif
diff --git a/src/sonic-config-engine/tests/dhcp-relay-enable-dhcp-server-sample.json b/src/sonic-config-engine/tests/dhcp-relay-enable-dhcp-server-sample.json
diff --git a/...nfig-engine/tests/sample_output/py2/docker-dhcp-relay-enable-dhcp-server.supervisord.conf b/...nfig-engine/tests/sample_output/py2/docker-dhcp-relay-enable-dhcp-server.supervisord.conf
diff --git a/...nic-config-engine/tests/sample_output/py2/docker-dhcp-relay-no-ip-helper.supervisord.conf b/...nic-config-engine/tests/sample_output/py2/docker-dhcp-relay-no-ip-helper.supervisord.conf
@@ -40,7 +40,7 @@ dependent_startup=true
 dependent_startup_wait_for=rsyslogd:running
 
 [group:dhcp-relay]
-programs=isc-dhcpv4-relay-Vlan1000,dhcp6relay
+programs=dhcprelayd,dhcp6relay
 
 [program:isc-dhcpv4-relay-Vlan1000]
 command=/usr/sbin/dhcrelay -d -m discard -a %%h:%%p %%P --name-alias-map-file /tmp/port-name-alias-map.txt -id Vlan1000 -iu Vlan2000 -iu PortChannel02 -iu PortChannel03 -iu PortChannel04 -iu PortChannel01 192.0.0.1 192.0.0.2
@@ -76,4 +76,12 @@ stderr_logfile=syslog
 dependent_startup=true
 dependent_startup_wait_for=isc-dhcpv4-relay-Vlan1000:running 
 
-
+[program:dhcprelayd]
+command=/usr/local/bin/dhcprelayd
+priority=3
+autostart=false
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=start:exited
diff --git a/src/sonic-config-engine/tests/sample_output/py2/docker-dhcp-relay.supervisord.conf b/src/sonic-config-engine/tests/sample_output/py2/docker-dhcp-relay.supervisord.conf
@@ -40,7 +40,7 @@ dependent_startup=true
 dependent_startup_wait_for=rsyslogd:running
 
 [group:dhcp-relay]
-programs=isc-dhcpv4-relay-Vlan1000,isc-dhcpv4-relay-Vlan2000,dhcp6relay
+programs=dhcprelayd,dhcp6relay
 
 [program:isc-dhcpv4-relay-Vlan1000]
 command=/usr/sbin/dhcrelay -d -m discard -a %%h:%%p %%P --name-alias-map-file /tmp/port-name-alias-map.txt -id Vlan1000 -iu Vlan2000 -iu PortChannel02 -iu PortChannel03 -iu PortChannel04 -iu PortChannel01 192.0.0.1 192.0.0.2
@@ -96,4 +96,12 @@ stderr_logfile=syslog
 dependent_startup=true
 dependent_startup_wait_for=isc-dhcpv4-relay-Vlan2000:running 
 
-
+[program:dhcprelayd]
+command=/usr/local/bin/dhcprelayd
+priority=3
+autostart=false
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=start:exited
diff --git a/...nic-config-engine/tests/sample_output/py3/docker-dhcp-relay-no-ip-helper.supervisord.conf b/...nic-config-engine/tests/sample_output/py3/docker-dhcp-relay-no-ip-helper.supervisord.conf
@@ -40,7 +40,7 @@ dependent_startup=true
 dependent_startup_wait_for=rsyslogd:running
 
 [group:dhcp-relay]
-programs=isc-dhcpv4-relay-Vlan1000,dhcp6relay
+programs=dhcprelayd,dhcp6relay
 
 [program:isc-dhcpv4-relay-Vlan1000]
 command=/usr/sbin/dhcrelay -d -m discard -a %%h:%%p %%P --name-alias-map-file /tmp/port-name-alias-map.txt -id Vlan1000 -iu Vlan2000 -iu PortChannel01 -iu PortChannel02 -iu PortChannel03 -iu PortChannel04 192.0.0.1 192.0.0.2
@@ -76,4 +76,12 @@ stderr_logfile=syslog
 dependent_startup=true
 dependent_startup_wait_for=isc-dhcpv4-relay-Vlan1000:running 
 
-
+[program:dhcprelayd]
+command=/usr/local/bin/dhcprelayd
+priority=3
+autostart=false
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=start:exited
diff --git a/src/sonic-config-engine/tests/sample_output/py3/docker-dhcp-relay.supervisord.conf b/src/sonic-config-engine/tests/sample_output/py3/docker-dhcp-relay.supervisord.conf
@@ -40,7 +40,7 @@ dependent_startup=true
 dependent_startup_wait_for=rsyslogd:running
 
 [group:dhcp-relay]
-programs=isc-dhcpv4-relay-Vlan1000,isc-dhcpv4-relay-Vlan2000,dhcp6relay
+programs=dhcprelayd,dhcp6relay
 
 [program:isc-dhcpv4-relay-Vlan1000]
 command=/usr/sbin/dhcrelay -d -m discard -a %%h:%%p %%P --name-alias-map-file /tmp/port-name-alias-map.txt -id Vlan1000 -iu Vlan2000 -iu PortChannel01 -iu PortChannel02 -iu PortChannel03 -iu PortChannel04 192.0.0.1 192.0.0.2
@@ -96,4 +96,12 @@ stderr_logfile=syslog
 dependent_startup=true
 dependent_startup_wait_for=isc-dhcpv4-relay-Vlan2000:running 
 
-
+[program:dhcprelayd]
+command=/usr/local/bin/dhcprelayd
+priority=3
+autostart=false
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=start:exited
diff --git a/src/sonic-config-engine/tests/test_j2files.py b/src/sonic-config-engine/tests/test_j2files.py
@@ -154,36 +154,16 @@ def test_ports_json(self):
     def test_dhcp_relay(self):
         # Test generation of wait_for_intf.sh
         dhc_sample_data = os.path.join(self.test_dir, "dhcp-relay-sample.json")
-        enable_dhcp_server_sample_data = os.path.join(self.test_dir, "dhcp-relay-enable-dhcp-server-sample.json")
         template_path = os.path.join(self.test_dir, '..', '..', '..', 'dockers', 'docker-dhcp-relay', 'wait_for_intf.sh.j2')
         argument = ['-m', self.t0_minigraph, '-j', dhc_sample_data, '-p', self.t0_port_config, '-t', template_path]
         self.run_script(argument, output_file=self.output_file)
         self.assertTrue(utils.cmp(os.path.join(self.test_dir, 'sample_output', utils.PYvX_DIR, 'wait_for_intf.sh'), self.output_file))
 
-        # Test generation of docker-dhcp-relay.supervisord.conf witout dhcp_server feature entry
         template_path = os.path.join(self.test_dir, '..', '..', '..', 'dockers', 'docker-dhcp-relay', 'docker-dhcp-relay.supervisord.conf.j2')
         argument = ['-m', self.t0_minigraph, '-p', self.t0_port_config, '-t', template_path]
         self.run_script(argument, output_file=self.output_file)
         self.assertTrue(utils.cmp(os.path.join(self.test_dir, 'sample_output', utils.PYvX_DIR, 'docker-dhcp-relay.supervisord.conf'), self.output_file))
 
-        # Test generation of docker-dhcp-relay.supervisord.conf with disabled dhcp_server feature
-        template_path = os.path.join(self.test_dir, '..', '..', '..', 'dockers', 'docker-dhcp-relay',
-                                     'docker-dhcp-relay.supervisord.conf.j2')
-        argument = ['-m', self.t0_minigraph, '-j', dhc_sample_data, '-p', self.t0_port_config, '-t', template_path]
-        self.run_script(argument, output_file=self.output_file)
-        self.assertTrue(utils.cmp(os.path.join(self.test_dir, 'sample_output', utils.PYvX_DIR,
-                                               'docker-dhcp-relay.supervisord.conf'), self.output_file))
-
-        # Test generation of docker-dhcp-relay.supervisord.conf with enabled dhcp_server feature
-        template_path = os.path.join(self.test_dir, '..', '..', '..', 'dockers', 'docker-dhcp-relay',
-                                     'docker-dhcp-relay.supervisord.conf.j2')
-        argument = ['-m', self.t0_minigraph, '-j', enable_dhcp_server_sample_data, '-p', self.t0_port_config, '-t',
-                    template_path]
-        self.run_script(argument, output_file=self.output_file)
-        self.assertTrue(utils.cmp(os.path.join(self.test_dir, 'sample_output', utils.PYvX_DIR,
-                                               'docker-dhcp-relay-enable-dhcp-server.supervisord.conf'),
-                                  self.output_file))
-
         # Test generation of docker-dhcp-relay.supervisord.conf when a vlan is missing ip/ipv6 helpers
         template_path = os.path.join(self.test_dir, '..', '..', '..', 'dockers', 'docker-dhcp-relay',
                                      'docker-dhcp-relay.supervisord.conf.j2')

diff --git a/src/sonic-dhcp-server/dhcp_server/common/dhcp_db_monitor.py b/src/sonic-dhcp-server/dhcp_server/common/dhcp_db_monitor.py
@@ -12,6 +12,7 @@
 VLAN = "VLAN"
 VLAN_MEMBER = "VLAN_MEMBER"
 VLAN_INTERFACE = "VLAN_INTERFACE"
+FEATURE = "FEATURE"
 
 
 class ConfigDbEventChecker(object):
@@ -343,6 +344,60 @@ def _process_check(self, key, op, entry, enabled_dhcp_interfaces):
         return False
 
 
+class DhcpServerFeatureStateChecker(ConfigDbEventChecker):
+    """
+    This event checker interested in dhcp_server feature state change in FEATURE table
+    """
+    table_name = FEATURE
+
+    def __init__(self, sel, db):
+        self.table_name = FEATURE
+        ConfigDbEventChecker.__init__(self, sel, db)
+
+    def _get_parameter(self, db_snapshot):
+        return ConfigDbEventChecker.get_parameter_by_name(db_snapshot, "dhcp_server_feature_enabled")
+
+    def _process_check(self, key, op, entry, dhcp_server_feature_enabled):
+        if key != "dhcp_server":
+            return False
+        if op == "DEL":
+            return dhcp_server_feature_enabled
+        for field, value in entry:
+            if field != "state":
+                continue
+            return value == "enabled" and not dhcp_server_feature_enabled or \
+                value == "disabled" and dhcp_server_feature_enabled
+        return False
+
+
+def _enable_monitor_checkers(checker_names, checker_dict):
+    """
+    Enable checkers
+    Args:
+        checker_names: set of tables checker to be enable
+        checker_dict: check_dict in monitor
+    """
+    for checker in checker_names:
+        if checker not in checker_dict:
+            syslog.syslog(syslog.LOG_ERR, "Cannot find checker for {} in checker_dict".format(checker))
+            continue
+        checker_dict[checker].enable()
+
+
+def _disable_monitor_checkers(checker_names, checker_dict):
+    """
+    Disable checkers
+    Args:
+        checker_names: set contains name of tables need to be disable
+        checker_dict: check_dict in monitor
+    """
+    for checker in checker_names:
+        if checker not in checker_dict:
+            syslog.syslog(syslog.LOG_ERR, "Cannot find checker for {} in checker_dict".format(checker))
+            continue
+        checker_dict[checker].disable()
+
+
 class DhcpRelaydDbMonitor(object):
     checker_dict = {}
 
@@ -354,17 +409,21 @@ def __init__(self, db_connector, sel, checkers, select_timeout=DEFAULT_SELECT_TI
         for checker in checkers:
             self.checker_dict[checker.get_class_name()] = checker
 
-    def enable_checker(self, checker_names):
+    def enable_checkers(self, checker_names):
         """
         Enable checkers
         Args:
             checker_names: set of tables checker to be enable
         """
-        for table in checker_names:
-            if table not in self.checker_dict:
-                syslog.syslog(syslog.LOG_ERR, "Cannot find checker for {} in checker_dict".format(table))
-                continue
-            self.checker_dict[table].enable()
+        _enable_monitor_checkers(checker_names, self.checker_dict)
+
+    def disable_checkers(self, checker_names):
+        """
+        Disable checkers
+        Args:
+            checker_names: set contains name of tables need to be disable
+        """
+        _disable_monitor_checkers(checker_names, self.checker_dict)
 
     def check_db_update(self, db_snapshot):
         """
@@ -376,10 +435,13 @@ def check_db_update(self, db_snapshot):
         """
         state, _ = self.sel.select(self.select_timeout)
         if state == swsscommon.Select.TIMEOUT or state != swsscommon.Select.OBJECT:
-            return (False, False, False)
-        return (self.checker_dict["DhcpServerTableIntfEnablementEventChecker"].check_update_event(db_snapshot),
-                self.checker_dict["VlanTableEventChecker"].check_update_event(db_snapshot),
-                self.checker_dict["VlanIntfTableEventChecker"].check_update_event(db_snapshot))
+            return {}
+        check_res = {}
+        for name, checker in self.checker_dict.items():
+            if not checker.is_enabled():
+                continue
+            check_res[name] = checker.check_update_event(db_snapshot)
+        return check_res
 
 
 class DhcpServdDbMonitor(object):
@@ -399,23 +461,15 @@ def disable_checkers(self, checker_names):
         Args:
             checker_names: set contains name of tables need to be disable
         """
-        for table in checker_names:
-            if table not in self.checker_dict:
-                syslog.syslog(syslog.LOG_ERR, "Cannot find checker for {} in checker_dict".format(table))
-                continue
-            self.checker_dict[table].disable()
+        _disable_monitor_checkers(checker_names, self.checker_dict)
 
     def enable_checkers(self, checker_names):
         """
         Enable checkers
         Args:
             checker_names: set contains name of tables need to be enable
         """
-        for table in checker_names:
-            if table not in self.checker_dict:
-                syslog.syslog(syslog.LOG_ERR, "Cannot find checker for {} in checker_dict".format(table))
-                continue
-            self.checker_dict[table].enable()
+        _enable_monitor_checkers(checker_names, self.checker_dict)
 
     def check_db_update(self, db_snapshot):
         """