err:hcnCreateNetwork failed in Win32: Invalid JSON document string

[keyingliu]

We trying to run windows containers, but the kubernetes pod cannot be up during network setup. The CNI congiurations are:

{
    "cniVersion": "0.2.0",
    "name": "nat",
    "type": "nat",
    "master": "Ethernet",
    "ipam": {
        "subnet": "10.172.204.0/8",
        "routes": [
            {
                "GW": "10.172.204.178"
            }
        ]
    },
    "capabilities": {
        "portMappings": true,
        "dns": true
    }
}

The output from wincni.log

{"level":"debug","msg":"[cni-net] Plugin wcn-net version .","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"[net] Network interface: {Index:14 MTU:1500 Name:Ethernet HardwareAddr:54:bf:64:98:1d:c6 Flags:up|broadcast|multicast} with IP addresses: [2404:f801:10:124:883:4be4:12ff:53d4/64 fe80::883:4be4:12ff:53d4/64 10.172.204.178/24]","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"[net] Network interface: {Index:1 MTU:-1 Name:Loopback Pseudo-Interface 1 HardwareAddr: Flags:up|loopback|multicast} with IP addresses: [::1/128 127.0.0.1/8]","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"[net] Network interface: {Index:21 MTU:1500 Name:vEthernet (nat) HardwareAddr:00:15:5d:5f:9a:47 Flags:up|broadcast|multicast} with IP addresses: [fe80::c1ed:f301:c00e:2af6/64 172.27.0.1/20]","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"[cni-net] Plugin started.","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"[cni-net] Processing ADD command with args {ContainerID:dcc9786445818f4a843162bfaf0c164d4617ece21ddc692c6ffb554462bafac6 Netns:a19ed0b3-b149-4fd2-9457-66815769ad99 IfName:eth0 Args:K8S_POD_INFRA_CONTAINER_ID=dcc9786445818f4a843162bfaf0c164d4617ece21ddc692c6ffb554462bafac6;K8S_POD_UID=f3c02187-8def-4311-9b2c-13fd75b5440f;IgnoreUnknown=1;K8S_POD_NAMESPACE=kube-system;K8S_POD_NAME=kube-flannel-ds-windows-amd64-tbvjd Path:c:/opt/cni/bin}.","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"[cni-net] Read network configuration \u0026{CniVersion:0.2.0 Name:nat Type:nat Ipam:{Type: Environment: AddrSpace: Subnet:10.172.204.0/8 Address: QueryInterval: Routes:[{Dst:{IP:\u003cnil\u003e Mask:\u003cnil\u003e} GW:10.172.204.178}]} DNS:{Nameservers:[] Domain: Search:[] Options:[]} OptionalFlags:{LocalRoutePortMapping:false AllowAclPortMapping:false ForceBridgeGateway:false EnableDualStack:false LoopbackDSR:false GatewayFromAdditionalRoutes:false} RuntimeConfig:{PortMappings:[] DNS:{Servers:[] Searches:[] Options:[]}} AdditionalRoutes:[] AdditionalArgs:[]}.","time":"2022-05-26T06:44:29-07:00"}
{"level":"info","msg":"[cni-net] Dual stack is disabled","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"Parsing port mappings from []","time":"2022-05-26T06:44:29-07:00"}
{"level":"info","msg":"[cni-net] Creating network.","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"hcn::HostComputeNetwork::Create id=","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"hcn::HostComputeNetwork::Create JSON: {\"Name\":\"nat\",\"Type\":\"nat\",\"MacPool\":{},\"Dns\":{},\"Ipams\":[{\"Type\":\"Static\",\"Subnets\":[{\"IpAddressPrefix\":\"10.0.0.0/8\",\"Routes\":[{\"NextHop\":\"10.172.204.178\",\"DestinationPrefix\":\"0.0.0.0/0\"}]}]}],\"SchemaVersion\":{\"Major\":2,\"Minor\":0}}","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"hcnCreateNetwork failed in Win32: Invalid JSON document string. (0x803b001b) {\"Success\":false,\"Error\":\"Invalid JSON document string. \",\"ErrorCode\":2151350299}","time":"2022-05-26T06:44:29-07:00"}
{"level":"error","msg":"[cni-net] Failed to create network, err:hcnCreateNetwork failed in Win32: Invalid JSON document string. (0x803b001b) {\"Success\":false,\"Error\":\"Invalid JSON document string. \",\"ErrorCode\":2151350299}.","time":"2022-05-26T06:44:29-07:00"}
{"level":"debug","msg":"[cni-net] Plugin stopped.","time":"2022-05-26T06:44:29-07:00"}
{"level":"error","msg":"Failed to Execute network plugin, err:hcnCreateNetwork failed in Win32: Invalid JSON document string. (0x803b001b) {\"Success\":false,\"Error\":\"Invalid JSON document string. \",\"ErrorCode\":2151350299}.\n","time":"2022-05-26T06:44:29-07:00"}
-26T06:33:55-07:00"}

Windows Edition: Windows Server 2019 Datacenter

[MikeZappa87]

Hello, it looks like the example for nat is incorrect. Please disregard my previous.

[keyingliu]

More details: we are following the guide https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/adding-windows-nodes/, and windows node has joined the cluster and became ready, container runtime is containerd latest stable version, we saw the errors when this yaml was applied: kubectl apply -f https://github.com/kubernetes-sigs/sig-windows-tools/releases/latest/download/flannel-overlay.yml