Weave Quick Start

English | 简体中文

Weave, an open-source network solution, provides network connectivity and policies for containers by creating a virtual network, automatically discovering and connecting containers. Also known as a Kubernetes Container Network Interface (CNI) solution, Weave utilizes the built-in IPAM to allocate IP addresses for Pods by default, with limited visibility and IPAM capabilities for Pods. This page demonstrates how Weave and Spiderpool can be integrated to extend Weave's IPAM capabilities while preserving its original functions.

Prerequisites

A ready Kubernetes cluster without any CNI installed
Helm, Kubectl and Jq (optional)

Install

Install Weave:

kubectl apply -f  https://github.com/weaveworks/weave/releases/download/v2.8.1/weave-daemonset-k8s.yaml

Wait for Pod Running:

[root@node1 ~]# kubectl get po -n kube-system  | grep weave
weave-net-ck849                         2/2     Running     4     0   1m
weave-net-vhmqx                         2/2     Running     4     0   1m

Install Spiderpool
```
helm repo add spiderpool https://spidernet-io.github.io/spiderpool
helm repo update spiderpool
helm install spiderpool spiderpool/spiderpool --namespace kube-system --set multus.multusCNI.install=false
```
If you are mainland user who is not available to access ghcr.io，You can specify the parameter -set global.imageRegistryOverride=ghcr.m.daocloud.io to avoid image pulling failures for Spiderpool.

Specify the name of the NetworkAttachmentDefinition instance for the default CNI used by Multus via multus.multusCNI.defaultCniCRName. If the multus.multusCNI.defaultCniCRName option is provided, an empty NetworkAttachmentDefinition instance will be automatically generated upon installation. Otherwise, Multus will attempt to create a NetworkAttachmentDefinition instance based on the first CNI configuration found in the /etc/cni/net.d directory. If no suitable configuration is found, a NetworkAttachmentDefinition instance named default will be created to complete the installation of Multus.

Wait for Pod Running and create the IPPool used by Pod:
```
cat << EOF | kubectl apply -f -
apiVersion: spiderpool.spidernet.io/v2beta1
kind: SpiderIPPool
metadata:
  name: weave-ippool-v4
  labels:  
    ipam.spidernet.io/subnet-cidr: 10-32-0-0-12
spec:
  ips:
  - 10.32.0.100-10.32.50.200
  subnet: 10.32.0.0/12
EOF
```
Weave uses 10.32.0.0/12 as the cluster's default subnet, and thus a SpiderIPPool with the same subnet needs to be created in this case.
Verify installation

shell [root@node1 ~]# kubectl get po -n kube-system | grep spiderpool spiderpool-agent-7hhkz 1/1 Running 0 13m spiderpool-agent-kxf27 1/1 Running 0 13m spiderpool-controller-76798dbb68-xnktr 1/1 Running 0 13m spiderpool-init 0/1 Completed 0 13m [root@node1 ~]# kubectl get sp NAME VERSION SUBNET ALLOCATED-IP-COUNT TOTAL-IP-COUNT DISABLE weave-ippool-v4 4 10.32.0.0/12 0 12901 false

Switch `Weave`'s `IPAM` to Spiderpool

Change the ipam field of /etc/cni/net.d/10-weave.conflist on each node:

Change the following:

[root@node1 ~]# cat /etc/cni/net.d/10-weave.conflist
{
    "cniVersion": "0.3.0",
    "name": "weave",
    "plugins": [
        {
            "name": "weave",
            "type": "weave-net",
            "hairpinMode": true
        },
        {
            "type": "portmap",
            "capabilities": {"portMappings": true},
            "snat": true
        }
    ]
}

To:

{
    "cniVersion": "0.3.0",
    "name": "weave",
    "plugins": [
        {
            "name": "weave",
            "type": "weave-net",
            "ipam": {
              "type": "spiderpool"
            },
            "hairpinMode": true
        },
        {
            "type": "portmap",
            "capabilities": {"portMappings": true},
            "snat": true
        }
    ]
}

Alternatively, it can be changed with jq in one step. If jq is not installed, you can use the following command to install it:

# Take centos7 as an example
yum -y install jq

Change the CNI configuration file:

cat <<< $(jq '.plugins[0].ipam.type = "spiderpool" ' /etc/cni/net.d/10-weave.conflist) > /etc/cni/net.d/10-weave.conflist

Make sure to run this command at each node

Create applications

Specify that the Pods will be allocated IPs from that SpiderSubnet via the annotation ipam.spidernet.io/ippool:

[root@node1 ~]# cat << EOF | kubectl apply -f -
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
spec:
  replicas: 2
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      annotations:
        ipam.spidernet.io/ippool: '{"ipv4":["weave-ippool-v4"]}'
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx
        imagePullPolicy: IfNotPresent
        lifecycle: {}
        name: container-1
EOF

spec.template.metadata.annotations.ipam.spidernet.io/subnet: specifies that the Pods will be assigned IPs from SpiderSubnet: weave-ippool-v4.

The Pods have been created and allocated IP addresses from Spiderpool Subnets:

[root@node1 ~]# kubectl get po  -o wide
NAME                     READY   STATUS    RESTARTS   AGE   IP             NODE    NOMINATED NODE   READINESS GATES
nginx-5745d9b5d7-2rvn7   1/1     Running   0          8s    10.32.22.190   node1   <none>           <none>
nginx-5745d9b5d7-5ssck   1/1     Running   0          8s    10.32.35.87    node2   <none>           <none>

[root@node1 ~]# kubectl get sp
NAME              VERSION   SUBNET          ALLOCATED-IP-COUNT   TOTAL-IP-COUNT   DISABLE
weave-ippool-v4   4         10.32.0.0/12    2                    2                false

To test connectivity, let's use inter-node communication between Pods as an example:

[root@node1 ~]# kubectl exec  nginx-5745d9b5d7-2rvn7 -- ping 10.32.35.87 -c 2
PING 10.32.35.87 (10.32.35.87): 56 data bytes
64 bytes from 10.32.35.87: seq=0 ttl=64 time=4.561 ms
64 bytes from 10.32.35.87: seq=1 ttl=64 time=0.632 ms

--- 10.32.35.87 ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.632/2.596/4.561 ms

The test results indicate that IP allocation and network connectivity are normal. Spiderpool has extended the capabilities of Weave's IPAM. Next, you can go to Spiderpool to explore other features of Spiderpool.

Weave Quick Start

Prerequisites

Install

Switch Weave's IPAM to Spiderpool

Create applications

Switch `Weave`'s `IPAM` to Spiderpool