[swss]: Wait for vlan intf to start ndppd (#10036)

- Use the `wait_for_link.sh` script to delay ndppd start until after the VLAN interface is ready
- Avoids issue where ndppd tries to change interface attributes before the interface is ready

Signed-off-by: Lawrence Lee <lawlee@microsoft.com>

dockers/docker-orchagent/Dockerfile.j2

@@ -68,7 +68,6 @@ RUN apt-get purge -y          \
 
 COPY ["files/arp_update", "/usr/bin"]
 COPY ["arp_update.conf", "files/arp_update_vars.j2", "/usr/share/sonic/templates/"]
-COPY ["ndppd.conf", "/usr/share/sonic/templates/"]
 COPY ["enable_counters.py", "tunnel_packet_handler.py", "/usr/bin/"]
 COPY ["orchagent.sh", "swssconfig.sh", "buffermgrd.sh", "/usr/bin/"]
 COPY ["files/supervisor-proc-exit-listener", "/usr/bin"]

dockers/docker-orchagent/docker-init.j2

@@ -18,6 +18,7 @@ CFGGEN_PARAMS=" \
     -t /usr/share/sonic/templates/ndppd.conf.j2,/etc/ndppd.conf \
     -t /usr/share/sonic/templates/critical_processes.j2,/etc/supervisor/critical_processes \
     -t /usr/share/sonic/templates/supervisord.conf.j2,/etc/supervisor/conf.d/supervisord.conf
+    -t /usr/share/sonic/templates/wait_for_link.sh.j2,/usr/bin/wait_for_link.sh \
 "
 VLAN=$(sonic-cfggen $CFGGEN_PARAMS)
 

dockers/docker-orchagent/ndppd.conf

@@ -1,9 +0,0 @@
-[program:ndppd]
-command=/usr/sbin/ndppd
-priority=7
-autostart=false
-autorestart=unexpected
-stdout_logfile=syslog
-stderr_logfile=syslog
-dependent_startup=true
-dependent_startup_wait_for=vlanmgrd:running

dockers/docker-orchagent/supervisord.conf.j2

@@ -299,3 +299,28 @@ stderr_logfile=syslog
 dependent_startup=true
 dependent_startup_wait_for=swssconfig:exited
 {%- endif %}
+
+{% if is_fabric_asic == 0 %}
+[program:ndppd]
+command=/usr/sbin/ndppd
+priority=7
+autostart=false
+autorestart=unexpected
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=wait_for_link:exited
+{%- endif %}
+
+{% if is_fabric_asic == 0 %}
+[program:wait_for_link]
+command=/usr/bin/wait_for_link.sh
+priority=7
+autostart=false
+autorestart=false
+startsecs=0
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=swssconfig:exited
+{%- endif %}

dockers/docker-orchagent/wait_for_link.sh.j2

@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+
+VLAN_TABLE_PREFIX="VLAN_TABLE"
+
+function wait_until_iface_ready
+{
+    TABLE_PREFIX=$1
+    IFACE=$2
+
+    echo "Waiting until interface $IFACE is ready..."
+
+    # Wait for the interface to come up
+    # (i.e., interface is present in STATE_DB and state is "ok")
+    while true; do
+        RESULT=$(sonic-db-cli STATE_DB HGET "${TABLE_PREFIX}|${IFACE}" "state" 2> /dev/null)
+        if [ x"$RESULT" == x"ok" ]; then
+            break
+        fi
+
+        sleep 1
+    done
+
+    echo "Interface ${IFACE} is ready!"
+}
+
+
+# Wait for all interfaces to be up and ready
+{% for (name, prefix) in VLAN_INTERFACE|pfx_filter %}
+wait_until_iface_ready ${VLAN_TABLE_PREFIX} {{ name }}
+{% endfor %}