Disable TX Checksum Offload

nodeup/pkg/model/networking/flannel.go

@@ -0,0 +1,55 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package networking
+
+import (
+	"k8s.io/kops/nodeup/pkg/model"
+	"k8s.io/kops/upup/pkg/fi"
+	"k8s.io/kops/upup/pkg/fi/nodeup/nodetasks"
+	"k8s.io/kops/util/pkg/distributions"
+)
+
+// FlannelBuilder writes the Amazon VPC CNI configuration
+type FlannelBuilder struct {
+	*model.NodeupModelContext
+}
+
+var _ fi.NodeupModelBuilder = &FlannelBuilder{}
+
+// Build is responsible for configuring the network cni
+func (b *FlannelBuilder) Build(c *fi.NodeupModelBuilderContext) error {
+	if b.NodeupConfig.Networking.Flannel == nil {
+		return nil
+	}
+
+	if b.Distribution == distributions.DistributionUbuntu2404 {
+		// https://github.com/flannel-io/flannel/blob/master/Documentation/troubleshooting.md#nat
+		c.AddTask(&nodetasks.File{
+			Path: "/etc/udev/rules.d/90-flannel.rules",
+			Contents: fi.NewStringResource(
+				`SUBSYSTEM=="net", ACTION=="add|change|move", ENV{INTERFACE}=="flannel.1", RUN+="/usr/sbin/ethtool -K flannel.1 tx-checksum-ip-generic off"`,
+			),
+			Type: nodetasks.FileType_File,
+			OnChangeExecute: [][]string{
+				{"udevadm", "control", "--reload-rules"},
+				{"udevadm", "trigger"},
+			},
+		})
+	}
+
+	return nil
+}

upup/pkg/fi/nodeup/command.go

@@ -323,6 +323,7 @@ func (c *NodeUpCommand) Run(out io.Writer) error {
 	loader.Builders = append(loader.Builders, &networking.CalicoBuilder{NodeupModelContext: modelContext})
 	loader.Builders = append(loader.Builders, &networking.CiliumBuilder{NodeupModelContext: modelContext})
 	loader.Builders = append(loader.Builders, &networking.AmazonVPCRoutedENIBuilder{NodeupModelContext: modelContext})
+	loader.Builders = append(loader.Builders, &networking.FlannelBuilder{NodeupModelContext: modelContext})
 	loader.Builders = append(loader.Builders, &networking.KuberouterBuilder{NodeupModelContext: modelContext})
 
 	loader.Builders = append(loader.Builders, &model.BootstrapClientBuilder{NodeupModelContext: modelContext})