Updated LLDP startup configuration for multi-asic (sonic-net#15440)

What I did:
Changes in LLDP Configuration to handle this:

Enable LLDP only on front panel interfaces.
Why I did:
This is done to free up CPU cycle as we don't see use for that in multi-asic and also for Chassis we have disable lldp docker on supervisor so there is no lldp peering even if send LLDP BPDU on backplane ports

For multi-asic do not generate lldpd.conf with eth0 related configuration
Why I did:
In namespace lldp docker there is no need to generate eth0 configuration. It gives not needed errror message as seen here sonic-net#15382

How I did it:
Instead of relying on DEVICE_METADTA sub_role we are using NAMESPACE_ID environmental variable (passed to all docker instance) which will be > 0 for multiasic docker instance and not define for global/host docker instance.

---------

Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>

Author: abdosi

dockers/docker-lldp/docker-lldp-init.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
 #Generate supervisord.conf based on device metadata
 mkdir -p /etc/supervisor/conf.d/
-sonic-cfggen -d -t /usr/share/sonic/templates/supervisord.conf.j2 > /etc/supervisor/conf.d/supervisord.conf
+sonic-cfggen -d -a "{\"namespace_id\":\"$NAMESPACE_ID\"}" -t /usr/share/sonic/templates/supervisord.conf.j2 > /etc/supervisor/conf.d/supervisord.conf
 exec /usr/local/bin/supervisord

dockers/docker-lldp/lldpd.conf.j2

@@ -8,12 +8,14 @@
 {% endfor %}
 {% endif %}
 {% if mgmt_if %}
+{% if not (namespace_id is defined and namespace_id|length) %}
 {# If MGMT port alias is available, use it for port ID subtype, otherwise use port name #}
 {% if MGMT_PORT and MGMT_PORT[mgmt_if.port_name] and MGMT_PORT[mgmt_if.port_name].alias %}
 configure ports eth0 lldp portidsubtype local {{ MGMT_PORT[mgmt_if.port_name].alias }}
 {% else %}
 configure ports eth0 lldp portidsubtype local {{ mgmt_if.port_name }}
 {% endif %}
+{% endif %}
 configure system ip management pattern {{ mgmt_if.ipv4 }}
 {% endif %}
 configure system hostname {{ DEVICE_METADATA['localhost']['hostname'] }}

dockers/docker-lldp/lldpmgrd

@@ -22,9 +22,8 @@ try:
 
     from sonic_py_common import daemon_base
     from swsscommon import swsscommon
-    from sonic_py_common.interface import inband_prefix, recirc_prefix
+    from sonic_py_common.interface import inband_prefix, recirc_prefix, backplane_prefix
     from sonic_py_common import device_info
-
 except ImportError as err:
     raise ImportError("%s - required module not found" % str(err))
 
@@ -138,9 +137,8 @@ class LldpManager(daemon_base.DaemonBase):
         """
         port_desc = None
 
-        # Skip recirc and inband interface prefixes. These are recycle ports exposed in PORT_TABLE for
-        # asic-to-asic communication in VOQ based chassis system. We do not configure LLDP on these.
-        if port_name.startswith(inband_prefix()) or port_name.startswith(recirc_prefix()):
+        # Skip special (recirc/inband) and backplane interfaces as we don't enable lldp on those interfaaces.
+        if any([port_name.startswith(inband_prefix()),port_name.startswith(recirc_prefix()),port_name.startswith(backplane_prefix())]):
             return
 
         # Get the port alias. If None or empty string, use port name instead

dockers/docker-lldp/start.sh

@@ -1,6 +1,7 @@
 #!/usr/bin/env bash
 CFGGEN_PARAMS=" \
     -d \
+    -a "{\"namespace_id\":\"$NAMESPACE_ID\"}" \
     -t /usr/share/sonic/templates/lldpd.conf.j2 \
     -y /etc/sonic/sonic_version.yml \
     -t /usr/share/sonic/templates/lldpdSysDescr.conf.j2 \

dockers/docker-lldp/supervisord.conf.j2

@@ -45,10 +45,10 @@ dependent_startup_wait_for=rsyslogd:running
 # - `-dd` means to stay in foreground, log warnings to console
 # - `-ddd` means to stay in foreground, log warnings and info to console
 # - `-dddd` means to stay in foreground, log all to console
-{% if DEVICE_METADATA['localhost']['sub_role'] is defined and DEVICE_METADATA['localhost']['sub_role']|length %}
-command=/usr/sbin/lldpd -d -I Ethernet* -C Ethernet*
+{% if namespace_id is defined and namespace_id|length %}
+command=/usr/sbin/lldpd -d -I Ethernet[0-9]* -C Ethernet[0-9]*
 {% else %}
-command=/usr/sbin/lldpd -d -I Ethernet*,eth0 -C eth0
+command=/usr/sbin/lldpd -d -I Ethernet[0-9]*,eth0 -C eth0
 {% endif %}
 priority=3
 autostart=false