Implement a health check for SONiC to enable the measurement of its startup time

images/sonic/Dockerfile

@@ -5,10 +5,12 @@ ENV LIBGUESTFS_BACKEND=direct
 RUN apt-get update && \
     apt-get --no-install-recommends install --yes \
         curl \
+        libpcap0.8 \
         iproute2 \
         linux-image-cloud-amd64 \
         python3 \
         python3-guestfs \
+        python3-scapy \
         qemu-system-x86 \
         telnet
 
@@ -18,3 +20,5 @@ COPY --from=ghcr.io/metal-stack/mini-lab-sonic:base /frr-pythontools.deb /frr-py
 ENTRYPOINT ["/launch.py"]
 
 COPY config_db.json mirror_tap_to_eth.sh launch.py /
+
+HEALTHCHECK --start-period=10s --interval=5s --retries=20 CMD test -f /healthy

images/sonic/launch.py

@@ -13,6 +13,9 @@
 import guestfs
 from guestfs import GuestFS
 
+from scapy.all import sniff
+from scapy.contrib.lldp import LLDPDU, LLDPDUChassisID
+
 BASE_IMG = '/sonic-vs.img'
 
 
@@ -168,6 +171,14 @@ def main():
     logger.info('Start QEMU')
     vm.start()
 
+    # SONiC will start sending LLDP packets after PortConfigDone is set in APPL database
+    logger.info('Wait until port configuration is done')
+    sniff(iface="eth0", filter="ether proto 0x88cc", stop_filter=is_port_configuration_done, store=0)
+
+    logger.info('Port configuration is done')
+    with open('/healthy', 'w'):
+        pass
+
     logger.info('Wait until QEMU is terminated')
     vm.wait()
 
@@ -218,5 +229,13 @@ def get_default_gateway() -> str:
             return socket.inet_ntoa(struct.pack("<L", int(fields[2], 16)))
 
 
+def is_port_configuration_done(packet):
+    if packet.haslayer(LLDPDUChassisID):
+        chassis_id_tlv = packet.getlayer(LLDPDUChassisID)
+        if chassis_id_tlv.subtype == LLDPDUChassisID.SUBTYPE_MAC_ADDRESS and chassis_id_tlv.id == get_mac_address('eth0'):
+            return True
+    return False
+
+
 if __name__ == '__main__':
     main()