flannel單節點的安裝

yum -y install etcd

[root@localhost sysconfig]# etcd --version
etcd Version: 3.3.11
Git SHA: 2cf9e51
Go Version: go1.10.3
Go OS/Arch: linux/amd64

修改vim /etc/etcd/etcd.conf

然後systemctl start etcd

yum -y install flannel 

[root@localhost sysconfig]# flanneld --version
0.7.1

systemctl start flanneld

systemctl status flanneld.service  報錯

[root@localhost opt]# systemctl start flanneld
Job for flanneld.service failed because a timeout was exceeded. See "systemctl status flanneld.service" and "journalctl -xe" for details.
[root@localhost opt]# systemctl status flanneld.service
● flanneld.service - Flanneld overlay address etcd agent
   Loaded: loaded (/usr/lib/systemd/system/flanneld.service; disabled; vendor preset: disabled)
   Active: activating (start) since Mon 2019-11-18 22:01:16 CST; 20s ago
 Main PID: 4146 (flanneld)
    Tasks: 7
   CGroup: /system.slice/flanneld.service
           └─4146 /usr/bin/flanneld -etcd-endpoints=http://192.168.218.136:2379 -etcd-prefix=/atomic.io/network -etcd-endpoints=h...

Nov 18 22:01:26 localhost.localdomain flanneld-start[4146]: E1118 22:01:26.711831    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:27 localhost.localdomain flanneld-start[4146]: E1118 22:01:27.713119    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:28 localhost.localdomain flanneld-start[4146]: E1118 22:01:28.714723    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:29 localhost.localdomain flanneld-start[4146]: E1118 22:01:29.715350    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:30 localhost.localdomain flanneld-start[4146]: E1118 22:01:30.716540    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:31 localhost.localdomain flanneld-start[4146]: E1118 22:01:31.717618    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:32 localhost.localdomain flanneld-start[4146]: E1118 22:01:32.718599    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:33 localhost.localdomain flanneld-start[4146]: E1118 22:01:33.719938    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:34 localhost.localdomain flanneld-start[4146]: E1118 22:01:34.721043    4146 network.go:102] failed to retrieve...fused
Nov 18 22:01:35 localhost.localdomain flanneld-start[4146]: E1118 22:01:35.721980    4146 network.go:102] failed to retrieve...fused
Hint: Some lines were ellipsized, use -l to show in full.
[root@localhost opt]# 

啓動時會讀取啓動/usr/lib/systemd/system/flanneld.service

注意-etcd-prefix=/automic.io/network 

   flanel讀取的網絡配置是這個文件，這個文件是在

注意：

FLANNEL_ETCD_PREFIX="/atomic.io/network"

這個FLANNEL_ETCD_PREFIX需要etcdctl手動去建立

etcdctl mk /atomic.io/network/config '{"Network":"172.20.0.0/16", "SubnetMin": "172.20.1.0", "SubnetMax": "172.20.20.0", "Backend":{"Type":"vxlan"}}'

[root@localhost sysconfig]# etcdctl mk /atomic.io/network/config '{"Network":"172.20.0.0/16", "SubnetMin": "172.20.1.0", "SubnetMax": "172.20.20.0", "Backend":{"Type":"vxlan"}}'
{"Network":"172.20.0.0/16", "SubnetMin": "172.20.1.0", "SubnetMax": "172.20.20.0", "Backend":{"Type":"vxlan"}}

172.20.15.1 爲在設置區間內隨機分配的subnet片段

[root@localhost etcd]# cat /run/flannel/docker
DOCKER_OPT_BIP="--bip=172.20.15.1/24"
DOCKER_OPT_IPMASQ="--ip-masq=true"
DOCKER_OPT_MTU="--mtu=1450"
DOCKER_NETWORK_OPTIONS=" --bip=172.20.15.1/24 --ip-masq=true --mtu=1450"
[root@localhost etcd]#

重啓docker

查看dcker 網絡

docker network inspect bridge

[root@localhost etcd]# docker network inspect bridge
[
    {
        "Name": "bridge",
        "Id": "686ad2bb5b07bd9e4e28abe56d9c1f69ebd12bdd7b2fc169bd791356b94a9c34",
        "Created": "2019-11-18T23:57:20.242084993+08:00",
        "Scope": "local",
        "Driver": "bridge",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": null,
            "Config": [
                {
                    "Subnet": "172.20.15.1/24",
                    "Gateway": "172.20.15.1"
                }
            ]
        },
        "Internal": false,
        "Attachable": false,
        "Containers": {},
        "Options": {
            "com.docker.network.bridge.default_bridge": "true",
            "com.docker.network.bridge.enable_icc": "true",
            "com.docker.network.bridge.enable_ip_masquerade": "true",
            "com.docker.network.bridge.host_binding_ipv4": "0.0.0.0",
            "com.docker.network.bridge.name": "docker0",
            "com.docker.network.driver.mtu": "1450"
        },
        "Labels": {}
    }
]
[root@localhost etcd]#

查看ip a 及ip r路由

[root@localhost etcd]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:c9:e3:41 brd ff:ff:ff:ff:ff:ff
    inet 192.168.218.136/24 brd 192.168.218.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::7ef0:7fad:153e:1e78/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:a8:5f:99 brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:a8:5f:99 brd ff:ff:ff:ff:ff:ff
5: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default
    link/ether 02:42:29:39:00:fd brd ff:ff:ff:ff:ff:ff
    inet 172.20.15.1/24 scope global docker0
       valid_lft forever preferred_lft forever
    inet6 fe80::42:29ff:fe39:fd/64 scope link
       valid_lft forever preferred_lft forever
38: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN group default
    link/ether c2:13:c2:e9:7f:ed brd ff:ff:ff:ff:ff:ff
    inet 172.20.15.0/32 scope global flannel.1
       valid_lft forever preferred_lft forever
    inet6 fe80::c013:c2ff:fee9:7fed/64 scope link
       valid_lft forever preferred_lft forever
[root@localhost etcd]# ip r
default via 192.168.218.2 dev ens33 proto static metric 100
172.20.0.0/16 dev flannel.1
172.20.15.0/24 dev docker0 proto kernel scope link src 172.20.15.1
192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1
192.168.218.0/24 dev ens33 proto kernel scope link src 192.168.218.136 metric 100
[root@localhost etcd]#