Kubernetes集群之Flannel网络

ls /etc/flanneld/ssl/
<<'COMMENT'
flanneld-key.pem  flanneld.pem
COMMENT

/root/local/bin/etcdctl \
--endpoints=${ETCD_ENDPOINTS} \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/flanneld/ssl/flanneld.pem \
--key-file=/etc/flanneld/ssl/flanneld-key.pem \
set ${FLANNEL_ETCD_PREFIX}/config '{"Network":"'${CLUSTER_CIDR}'", "SubnetLen": 24, "Backend": {"Type": "vxlan"}}'

<<'COMMENT'
2017-05-11 13:42:17.082810 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
{"Network":"172.30.0.0/16", "SubnetLen": 24, "Backend": {"Type": "vxlan"}}
COMMENT

mkdir flannel
wget https://github.com/coreos/flannel/releases/download/v0.7.1/flannel-v0.7.1-linux-amd64.tar.gz
tar -xzvf flannel-v0.7.1-linux-amd64.tar.gz -C flannel
sudo cp flannel/{flanneld,mk-docker-opts.sh} /root/local/bin

cat > flanneld.service <<EOF
[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
ExecStart=/root/local/bin/flanneld \\
  -etcd-cafile=/etc/kubernetes/ssl/ca.pem \\
  -etcd-certfile=/etc/flanneld/ssl/flanneld.pem \\
  -etcd-keyfile=/etc/flanneld/ssl/flanneld-key.pem \\
  -etcd-endpoints=${ETCD_ENDPOINTS} \\
  -etcd-prefix=${FLANNEL_ETCD_PREFIX} \\
  $FLANNEL_OPTIONS
ExecStartPost=/root/local/bin/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/docker
Restart=on-failure

[Install]
WantedBy=multi-user.target
RequiredBy=docker.service
EOF

# 启动 flannelds
sudo cp flanneld.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable flanneld

<<'COMMENT'
Created symlink from /etc/systemd/system/multi-user.target.wants/flanneld.service to /etc/systemd/system/flanneld.service.
Created symlink from /etc/systemd/system/docker.service.requires/flanneld.service to /etc/systemd/system/flanneld.service.
COMMENT

sudo systemctl start flanneld
sudo systemctl status flanneld

<<'COMMENT'
● flanneld.service - Flanneld overlay address etcd agent
   Loaded: loaded (/etc/systemd/system/flanneld.service; enabled; vendor preset: disabled)
   Active: active (running) since Thu 2017-05-11 13:54:34 CST; 3s ago
  Process: 4946 ExecStartPost=/root/local/bin/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/docker (code=exited, status=0/SUCCESS)
 Main PID: 4938 (flanneld)
   CGroup: /system.slice/flanneld.service
           └─4938 /root/local/bin/flanneld -etcd-cafile=/etc/kubernetes/ssl/ca.pem -etcd-certfile=/etc/flanneld/ssl/flanneld.pem -etcd-keyfile=/etc/flan...

May 11 13:54:33 192-168-1-171.master systemd[1]: Starting Flanneld overlay address etcd agent...
May 11 13:54:34 192-168-1-171.master flanneld[4938]: warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
May 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.030738    4938 main.go:132] Installing signal handlers
May 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.033839    4938 manager.go:149] Using interface with name ens160 and address ...68.1.171
May 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.033937    4938 manager.go:166] Defaulting external address to interface addr...8.1.171)
May 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.114080    4938 local_manager.go:179] Picking subnet in range 172.30.1.0 ... ...30.255.0
May 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.118711    4938 manager.go:250] Lease acquired: 172.30.87.0/24
May 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.119706    4938 network.go:58] Watching for L3 misses
May 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.119739    4938 network.go:66] Watching for new subnet leases
May 11 13:54:34 192-168-1-171.master systemd[1]: Started Flanneld overlay address etcd agent.
Hint: Some lines were ellipsized, use -l to show in full.
COMMENT

# 检查 flanneld 服务
journalctl  -u flanneld |grep 'Lease acquired'
<<'COMMENT'
AMay 11 13:54:34 192-168-1-171.master flanneld[4938]: I0511 13:54:34.118711    4938 manager.go:250] Lease acquired: 172.30.87.0/24
COMMENT

ifconfig flannel.1
<<'COMMENT'
flannel.1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1450
        inet 172.30.1.0  netmask 255.255.255.255  broadcast 0.0.0.0
        ether 3e:27:de:39:f1:1a  txqueuelen 0  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 2 overruns 0  carrier 0  collisions 0
COMMENT

# 检查分配给各 flanneld 的 Pod 网段信息
/root/local/bin/etcdctl \
--endpoints=${ETCD_ENDPOINTS} \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/flanneld/ssl/flanneld.pem \
--key-file=/etc/flanneld/ssl/flanneld-key.pem \
get ${FLANNEL_ETCD_PREFIX}/config

<<'COMMENT'
2017-05-11 13:59:47.686607 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
{"Network":"172.30.0.0/16", "SubnetLen": 24, "Backend": {"Type": "vxlan"}}
COMMENT


# 查看已分配的 Pod 子网段列表(/24)
/root/local/bin/etcdctl \
--endpoints=${ETCD_ENDPOINTS} \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/flanneld/ssl/flanneld.pem \
--key-file=/etc/flanneld/ssl/flanneld-key.pem \
ls ${FLANNEL_ETCD_PREFIX}/subnets

<<'COMMENT'
2017-05-11 14:00:17.969753 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
/kubernetes/network/subnets/172.30.87.0-24
COMMENT

# 查看某一 Pod 网段对应的 flanneld 进程监听的 IP 和网络参数
/root/local/bin/etcdctl \
--endpoints=${ETCD_ENDPOINTS} \
--ca-file=/etc/kubernetes/ssl/ca.pem \
--cert-file=/etc/flanneld/ssl/flanneld.pem \
--key-file=/etc/flanneld/ssl/flanneld-key.pem \
get ${FLANNEL_ETCD_PREFIX}/subnets/172.30.87.0-24

<<'COMMENT'
2017-05-11 14:00:58.398312 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
{"PublicIP":"192.168.1.171","BackendType":"vxlan","BackendData":{"VtepMAC":"3e:27:de:39:f1:1a"}}
COMMENT