flanneld安装部署
最主要的是让pod容器内部能互相联通，形成集群。
CNI 网络插件最主要的功能就是实现pod资源跨宿主机进行通讯
CNI 网络插件
flannel
calico
canal
contiv
OpenContrail
Kube-router
下载flannel: https://github.com/flannel/releases
在jackie21上部署
#cd /opt/src
#wget https:github.com/coreos/flannel/releases/download/v0.11.0/flannel-v0.11.0-linux-amd64.tar.gz
#mkdir /opt/flannel-v0.11.0
#tar xf flannel-v0.11.0-linux-amd-64.tar.gz -C /opt/flannel-v0.11.0/
#ln -s /opt/flannel-v0.11.0/ /opt/flannel
#cd flannel
#mkdir cert
#cd cert/
因为要和apserver通信，所以要配置client证书
cert]# scp jackie200:/opt/certs/ca.pem .
cert]# scp jackie200:/opt/certs/client.pem .
cert]# scp jackie200:/opt/certs/client-key.pem .
编辑环境变量env文件:
flannel ]#
vi /opt/flannel/subnet.env
FLANNEL_NETWORK=172.7.0.0/16
FLANNEL_SUBNET=172.7.21.1/24
FLANNEL_MTU=1500
FLANNEL_IPMASQ=false
创建启动脚本
jackie21上
vi /opt/flannel/flannel.sh
#!/bin/sh
./flanneld \
--public-ip=10.0.0.21 \
--etcd-endpoints=https://10.0.0.12:2379,https://10.0.0.21:2379,https://10.0.0.22:2379 \
--etcd-keyfile=./cert/client-key.pem \
--etcd-certfile=./cert/client.pem \
--etcd-cafile=./cert/ca.pem \
--iface=eth0 \
--subnet-file=./subnet.env \
--healthz-port=2401
chmod u+x flanneld.sh
创建日志存放目录
mkdir -p /data/logs/flanneld
在etcd中增加网络配置信息
cd /opt/etcd
测试使用host-gw模型:
#./etcdctl set /coreos.com/network/config ‘{“Network”: “172.7.0.0/16”, “Backend”: {“Type”: “host-gw”}}’
查看网络模型配置:
#./etcdctl get /coreos.com/network/config
编辑supervisor启动脚本:
vi /etc/supervisord.d/flannel.ini
[program:flanneld-7-21]
command=/opt/flannel/flanneld.sh ; the program (relative uses PATH, can take args)
numprocs=1 ; number of processes copies to start (def 1)
directory=/opt/flannel ; directory to cwd to before exec (def no cwd)
autostart=true ; start at supervisord start (default: true)
autorestart=true ; retstart at unexpected quit (default: true)
startsecs=30 ; number of secs prog must stay running (def. 1)
startretries=3 ; max # of serial start failures (default 3)
exitcodes=0,2 ; 'expected' exit codes for process (default 0,2)
stopsignal=QUIT ; signal used to kill process (default TERM)
stopwaitsecs=10 ; max num secs to wait b4 SIGKILL (default 10)
user=root ; setuid to this UNIX account to run the program
redirect_stderr=true ; redirect proc stderr to stdout (default false)
stdout_logfile=/data/logs/flanneld/flanneld.stdout.log ; stderr log path, NONE for none; default AUTO
stdout_logfile_maxbytes=64MB ; max # logfile bytes b4 rotation (default 50MB)
stdout_logfile_backups=4 ; # of stdout logfile backups (default 10)
stdout_capture_maxbytes=1MB ; number of bytes in 'capturemode' (default 0)
stdout_events_enabled=false ; emit events on stdout writes (default false)
更新supervisor配置:
supervisorctl update
这里需要修改iptables优化SNAT规则，否则在访问时，其他节点记录的是node节点的ip 10.4.7.21，而不是pod集群内部的172.7.21.x，红色部分按需修改
#yum install iptables-services -y
#iptables -t nat -D POSTROUTING -s 172.7.21.0/24 ! -o docker0 -j MASQUERADE
#iptables -t nat -I POSTROUTING -s 172.7.21.0/24 ! -d 172.7.0.0/16 ! -o docker0 -j MASQUERADE
#iptables-save |grep -i postrouting
#iptables-save > /etc/sysconfig/iptables
修改后会影响到docker原本的iptables链的规则，所以需要重启docker服务
#systemctl restart docker
配置vxlan模型：
cd /opt/etcd
./etcdctl set /coreos.com/network/config ‘{“Network”: “172.7.0.0/16”, “Backend”: {“Type”: “vxlan”}}’
重启flanneld：
#supervisorctl restart flanneld-7-21
可以发现多了一块网卡，这块网卡就是vxlan用于隧道通信的虚拟网卡：
配置vxlan跟host-gw混合模型：
./etcdctl set /coreos.com/network/config ‘{“Network”: “172.7.0.0/16”, “Backend”: {“Type”: “vxlan”,“Directrouting”: true}}’
重启flanneld：
#supervisorctl restart flanneld-7-21