fix: Remove unused bridge network (#183)

Author: honcao

parts/k8s/cloud-init/artifacts/cse_config.sh

@@ -334,6 +334,21 @@ ensureContainerd() {
   systemctlEnableAndStart containerd || exit {{GetCSEErrorCode "ERR_SYSTEMCTL_START_FAIL"}}
   enableCRISystemdMonitor
 }
+
+ensureNoBridgeDocker0 () {
+  # Define the name of the bridge you want to check and potentially delete
+  BRIDGE_NAME="docker0"
+  # Check if the bridge exists
+  if ip link show "$BRIDGE_NAME" &> /dev/null; then
+      # The bridge exists, so delete it
+      echo "Deleting bridge network $BRIDGE_NAME"
+      retrycmd 120 5 25 ip link delete "$BRIDGE_NAME" type bridge || exit {{GetCSEErrorCode "ERR_REMOVE_DOCKER_BRIDGE_FAIL"}}
+  else
+      # The bridge does not exist
+      echo "Bridge network $BRIDGE_NAME does not exist"
+  fi
+}
+
 {{end}}
 {{- if IsDockerContainerRuntime}}
 ensureDocker() {

parts/k8s/cloud-init/artifacts/cse_main.sh

@@ -314,6 +314,10 @@ else
   fi
 fi
 
+{{- if NeedsContainerd}}
+ensureNoBridgeDocker0
+{{end}}
+
 echo "CSE finished successfully"
 echo $(date),$(hostname), endcustomscript >>/opt/m
 mkdir -p /opt/azure/containers && touch /opt/azure/containers/provision.complete

pkg/engine/cse.go

@@ -80,6 +80,7 @@ var cseErrorCodes = map[string]int{
 	"ERR_DEB_DOWNLOAD_TIMEOUT":                   184,
 	"ERR_DEB_PKG_ADD_FAIL":                       185,
 	"ERR_VHD_FILE_NOT_FOUND":                     186,
+	"ERR_REMOVE_DOCKER_BRIDGE_FAIL":              187,
 }
 
 func GetCSEErrorCode(errorType string) int {