kubernetes-handbook/practice/flannel-installation.md

112 lines
4.2 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

## 安装flannel网络插件
所有的node节点都需要安装网络插件才能让所有的Pod加入到同一个局域网中本文是安装flannel网络插件的参考文档。
建议直接使用yum安装flanneld除非对版本有特殊需求默认安装的是0.7.1版本的flannel。
```shell
yum install -y flannel
```
service配置文件`/usr/lib/systemd/system/flanneld.service`。
```ini
[Unit]
Description=Flanneld overlay address etcd agent
After=network.target
After=network-online.target
Wants=network-online.target
After=etcd.service
Before=docker.service
[Service]
Type=notify
EnvironmentFile=/etc/sysconfig/flanneld
EnvironmentFile=-/etc/sysconfig/docker-network
ExecStart=/usr/bin/flanneld-start \
-etcd-endpoints=${ETCD_ENDPOINTS} \
-etcd-prefix=${ETCD_PREFIX} \
$FLANNEL_OPTIONS
ExecStartPost=/usr/libexec/flannel/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/docker
Restart=on-failure
[Install]
WantedBy=multi-user.target
RequiredBy=docker.service
```
`/etc/sysconfig/flanneld`配置文件:
```ini
# Flanneld configuration options
# etcd url location. Point this to the server where etcd runs
ETCD_ENDPOINTS="https://172.20.0.113:2379,https://172.20.0.114:2379,https://172.20.0.115:2379"
# etcd config key. This is the configuration key that flannel queries
# For address range assignment
ETCD_PREFIX="/kube-centos/network"
# Any additional options that you want to pass
FLANNEL_OPTIONS="-etcd-cafile=/etc/kubernetes/ssl/ca.pem -etcd-certfile=/etc/kubernetes/ssl/kubernetes.pem -etcd-keyfile=/etc/kubernetes/ssl/kubernetes-key.pem"
```
如果是多网卡例如vagrant环境则需要在FLANNEL_OPTIONS中增加指定的外网出口的网卡例如-iface=eth2
**在etcd中创建网络配置**
执行下面的命令为docker分配IP地址段。
```shell
etcdctl --endpoints=https://172.20.0.113:2379,https://172.20.0.114:2379,https://172.20.0.115:2379 \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/kubernetes/ssl/kubernetes.pem \
--key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
mkdir /kube-centos/network
etcdctl --endpoints=https://172.20.0.113:2379,https://172.20.0.114:2379,https://172.20.0.115:2379 \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/kubernetes/ssl/kubernetes.pem \
--key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
mk /kube-centos/network/config '{"Network":"172.30.0.0/16","SubnetLen":24,"Backend":{"Type":"vxlan"}}'
```
如果你要使用`host-gw`模式可以直接将vxlan改成`host-gw`即可。
**注**:参考[网络和集群性能测试](network-and-cluster-perfermance-test.md)那节,最终我们使用的`host-gw`模式关于flannel支持的backend模式见<https://github.com/coreos/flannel/blob/master/Documentation/backends.md>
**启动flannel**
```shell
systemctl daemon-reload
systemctl enable flanneld
systemctl start flanneld
systemctl status flanneld
```
现在查询etcd中的内容可以看到
```bash
$etcdctl --endpoints=${ETCD_ENDPOINTS} \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/kubernetes/ssl/kubernetes.pem \
--key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
ls /kube-centos/network/subnets
/kube-centos/network/subnets/172.30.14.0-24
/kube-centos/network/subnets/172.30.38.0-24
/kube-centos/network/subnets/172.30.46.0-24
$etcdctl --endpoints=${ETCD_ENDPOINTS} \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/kubernetes/ssl/kubernetes.pem \
--key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
get /kube-centos/network/config
{ "Network": "172.30.0.0/16", "SubnetLen": 24, "Backend": { "Type": "vxlan" } }
$etcdctl get /kube-centos/network/subnets/172.30.14.0-24
{"PublicIP":"172.20.0.114","BackendType":"vxlan","BackendData":{"VtepMAC":"56:27:7d:1c:08:22"}}
$etcdctl get /kube-centos/network/subnets/172.30.38.0-24
{"PublicIP":"172.20.0.115","BackendType":"vxlan","BackendData":{"VtepMAC":"12:82:83:59:cf:b8"}}
$etcdctl get /kube-centos/network/subnets/172.30.46.0-24
{"PublicIP":"172.20.0.113","BackendType":"vxlan","BackendData":{"VtepMAC":"e6:b2:fd:f6:66:96"}}
```
如果可以查看到以上内容证明flannel已经安装完成下一步是在node节点上安装和配置docker、kubelet、kube-proxy等请参考下一节[部署node节点](node-installation.md)。