- 理解Docker0
- 参数--link
- 自定义网络
- 网络连通
- 实战：部署redis集群
理解Docker0
清空所有环境，帮助学习网络的理解
# 移除所有镜像
[hekai@localhost ~]$ docker rm -f $(docker ps -aq)
# 移除所有容器
[hekai@localhost ~]$ docker rmi -f $(docker images -aq)
三个网络
# 问题：docker是如何处理容器网络访问的？
[hekai@localhost ~]$ docker run -d -P --name tomcat01 tomcat
# 查看容器的内部地址
[hekai@localhost ~]$ docker exec -it tomcat01 ip addr
1: lo: 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
131: eth0@if132: mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 172.17.0.2/16 brd 172.17.255.255 scope global eth0
valid_lft forever preferred_lft forever
[hekai@localhost ~]$
# 看linux能不能ping通容器内部
[hekai@localhost ~]$ ping 172.17.0.2
PING 172.17.0.2 (172.17.0.2) 56(84) bytes of data.
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.112 ms
64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.073 ms
# 显然是可以的！
# 但是两个容器之间能ping通吗？
原理
1、每启动一个docker容器，docker就会给docker容器分配一个ip，只要安装了docker，就会有一个网卡docker0桥接模式，使用的技术是 evth-pair技术！
再次查看本地ip，发现多了一个vethxxx
# 可以发现，容器内的是131，本地是132，因为容器带来的网卡都是一对一对的
# evth-pair 就是一对的虚拟设备接口，他们都是成对出现的，一段连着协议，一段彼此相连
# evth-pair 充当一个桥梁，连接各种虚拟网络设备的OpenStac, Docker容器之间的连接，
# OVS连接，都是使用evth-pair技术
3、测试两个容器之间是否可以ping通
# 首先再启动一个容器tomcat02
docker run -d -P --name tomcat02 tomcat
# 尝试ping
[hekai@localhost ~]$ docker exec -it tomcat02 ping 172.17.0.2
PING 172.17.0.2 (172.17.0.2) 56(84) bytes of data.
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.124 ms
64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.082 ms
^C
--- 172.17.0.2 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 22ms
rtt min/avg/max/mdev = 0.082/0.103/0.124/0.021 ms
# 结论：容器和容器之间是可以相互ping通的，tomcat01和tomcat02是公用一个路由器，docker0
所有的容器不指定网络情况下，都是docker0路由的，docker会给我们的容器分配一个默认的IP
小结
Docker使用的是Linux的桥接，宿主机中是一个Docker容器的网桥docker0
Docker中的所有网络接口都是虚拟的，转化效率高
只要容器被删除，网桥消失
查看网卡中的东西
[hekai@localhost ~]$ docker network ls
NETWORK ID NAME DRIVER SCOPE
1d62f1dd42f9 bridge bridge local
d3c7ee72696e host host local
a8f0c9a8baa0 none null local
[hekai@localhost ~]$ docker network inspect 1d62f1dd42f9
参数--link
思考：我们编写了一个微服务，database url=ip; 项目不重启，数据库ip换掉了，我们希望可以处理这个问题，可以通过名字来访问容器？
springcloud feign = 服务名
mysql ip很多
# 直接使用名字来ping是不行的
[hekai@localhost ~]$ docker exec -it tomcat02 ping tomcat01
ping: tomcat01: Name or service not known
# 如何解决这个问题？
# 使用--link启动一个tomcat03
[hekai@localhost ~]$ docker run -d -P --name tomcat03 --link tomcat02 tomcat
6a37229c4b6a8413231480376d053240fca653c38ab9204a68dc4c68d426de0b
[hekai@localhost ~]$
# 用tomcat03去pingtomcat02
[hekai@localhost ~]$ docker exec -it tomcat03 ping tomcat02
PING tomcat02 (172.17.0.3) 56(84) bytes of data.
64 bytes from tomcat02 (172.17.0.3): icmp_seq=1 ttl=64 time=0.115 ms
64 bytes from tomcat02 (172.17.0.3): icmp_seq=2 ttl=64 time=0.079 ms
^C
--- tomcat02 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 32ms
rtt min/avg/max/mdev = 0.079/0.097/0.115/0.018 ms
[hekai@localhost ~]$
# 发现可以ping通
# 反向可以ping通吗？
[hekai@localhost ~]$ docker exec -it tomcat02 ping tomcat03
ping: tomcat03: Name or service not known
# 显然不行，因为没有配置
探究：inspect
[hekai@localhost ~]$ docker network ls
NETWORK ID NAME DRIVER SCOPE
1d62f1dd42f9 bridge bridge local
d3c7ee72696e host host local
a8f0c9a8baa0 none null local
[hekai@localhost ~]$ docker network inspect 1d62f1dd42f9
但是inspect查看tomcat03时，信息太多，不容易看到怎么连接过去tomcat2的
但是tomcat03是否在本地配置了tomcat02的配置？
# 查看hosts配置，--link原理发现！
[hekai@localhost ~]$ docker exec -i tomcat03 cat /etc/hosts
127.0.0.1 localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
172.17.0.3 tomcat02 4ab5dad3ff46
172.17.0.4 6a37229c4b6a
# 增加了172.17.0.3 tomcat02 4ab5dad3ff46
现在玩Docker已经不建议使用--link了！
自定义网络，不适用docker0
docker0问题：不支持容器名连接访问
自定义网络
查看所有docker网络
网络模式
bridge：桥接模式（默认，自己创建也是用bridge模式）
none：不配置网络
host：和宿主机共享网络
container：容器之间直接互连（局限很大，少用）
测试
# 直接启动的时候，--net bridge是默认参数
[hekai@localhost ~]$ docker run -d -P --name tomcat01 tomcat
[hekai@localhost ~]$ docker run -d -P --name tomcat01 --net bridge tomcat
# docker0特点：默认，域名不能用来访问，--link可以打通连接
# 可以自定义一个网络，docker network create
[hekai@localhost ~]$ docker network create --help
Usage: docker network create [OPTIONS] NETWORK
Create a network
Options:
--attachable Enable manual container attachment
--aux-address map Auxiliary IPv4 or IPv6 addresses used by Network driver (default map[])
--config-from string The network from which to copy the configuration
--config-only Create a configuration only network
-d, --driver string Driver to manage the Network (default "bridge")
--gateway strings IPv4 or IPv6 Gateway for the master subnet
--ingress Create swarm routing-mesh network
--internal Restrict external access to the network
--ip-range strings Allocate container ip from a sub-range
--ipam-driver string IP Address Management Driver (default "default")
--ipam-opt map Set IPAM driver specific options (default map[])
--ipv6 Enable IPv6 networking
--label list Set metadata on a network
-o, --opt map Set driver specific options (default map[])
--scope string Control the network's scope
--subnet strings Subnet in CIDR format that represents a network segment
# --subnet 子网掩码，一定要配置(这里一定要注意网关，比如是172开头的配置了192开头可能影响后续网络连接！！！)
[hekai@localhost ~]$ docker network create --driver bridge --subnet 192.168.0.0/16 --gateway 192.168.0.1 mynet
5590469f454a0fada3e9614bd541655988950929a77c4a39069e0e63d33e313a
[hekai@localhost ~]$ docker network ls
NETWORK ID NAME DRIVER SCOPE
1d62f1dd42f9 bridge bridge local
d3c7ee72696e host host local
5590469f454a mynet bridge local
a8f0c9a8baa0 none null local
[hekai@localhost ~]$
# 查看mynet的配置
[hekai@localhost ~]$ docker network inspect mynet
[
{
"Name": "mynet",
"Id": "5590469f454a0fada3e9614bd541655988950929a77c4a39069e0e63d33e313a",
"Created": "2021-03-16T12:07:37.248233125+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "192.168.0.0/16",
"Gateway": "192.168.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {},
"Options": {},
"Labels": {}
}
]
# 自己的网络就配置好了
# 启动两个容器
[hekai@localhost ~]$ docker run -d -P --name tomcat-net-01 --net mynet tomcat
b32fc7ec5a6e1319e8e7910632c80a57eb5927f93313f1d4a074fd9023aada81
[hekai@localhost ~]$ docker run -d -P --name tomcat-net-02 --net mynet tomcat
77a9ca3cdc097796be715c0e6440c63db7bfee37e6a119086b140dece46a8b1c
[hekai@localhost ~]$
[hekai@localhost ~]$ docker inspect mynet
[
{
"Name": "mynet",
"Id": "5590469f454a0fada3e9614bd541655988950929a77c4a39069e0e63d33e313a",
"Created": "2021-03-16T12:07:37.248233125+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "192.168.0.0/16",
"Gateway": "192.168.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"77a9ca3cdc097796be715c0e6440c63db7bfee37e6a119086b140dece46a8b1c": {
"Name": "tomcat-net-02",
"EndpointID": "0f29727d7b36b8757bf9d40350d12fe3d6455297d7983b3bf01120aa2a7bd577",
"MacAddress": "02:42:c0:a8:00:03",
"IPv4Address": "192.168.0.3/16",
"IPv6Address": ""
},
"b32fc7ec5a6e1319e8e7910632c80a57eb5927f93313f1d4a074fd9023aada81": {
"Name": "tomcat-net-01",
"EndpointID": "1955652ae224c426c79771670a396750e570ce56792640faf0664eda30ab70e9",
"MacAddress": "02:42:c0:a8:00:02",
"IPv4Address": "192.168.0.2/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]
# 再次测试ping连接
[hekai@localhost ~]$ docker exec -it tomcat-net-01 ping 192.168.0.3
PING 192.168.0.3 (192.168.0.3) 56(84) bytes of data.
64 bytes from 192.168.0.3: icmp_seq=1 ttl=64 time=0.130 ms
64 bytes from 192.168.0.3: icmp_seq=2 ttl=64 time=0.088 ms
^C
--- 192.168.0.3 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 27ms
rtt min/avg/max/mdev = 0.088/0.109/0.130/0.021 ms
[hekai@localhost ~]$ docker exec -it tomcat-net-01 ping tomcat-net-02
PING tomcat-net-02 (192.168.0.3) 56(84) bytes of data.
64 bytes from tomcat-net-02.mynet (192.168.0.3): icmp_seq=1 ttl=64 time=0.102 ms
64 bytes from tomcat-net-02.mynet (192.168.0.3): icmp_seq=2 ttl=64 time=0.084 ms
64 bytes from tomcat-net-02.mynet (192.168.0.3): icmp_seq=3 ttl=64 time=0.091 ms
64 bytes from tomcat-net-02.mynet (192.168.0.3): icmp_seq=4 ttl=64 time=0.095 ms
^C
--- tomcat-net-02 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 59ms
rtt min/avg/max/mdev = 0.084/0.093/0.102/0.006 ms
# 没有--link，也可以根据名字ping通！
自定义的网络docker都已经帮我们维护好了对应的关系，推荐我们平时这样使用网络
好处
redis # 不同的集群使用不同的网络，保证集群是安全和健康的
mysql # 不同的集群使用不同的网络，保证集群是安全和健康的
网络连通
[hekai@localhost ~]$ docker exec -it tomcat01 ping tomcat-net-01
ping: tomcat-net-01: Name or service not known
[hekai@localhost ~]$
# 显然直接连接不行
# 测试打通 tomcat01 tomcat-net-01
[hekai@localhost ~]$ docker network connect mynet tomcat01
[hekai@localhost ~]$ docker inspect mynet
[
{
"Name": "mynet",
"Id": "5590469f454a0fada3e9614bd541655988950929a77c4a39069e0e63d33e313a",
"Created": "2021-03-16T12:07:37.248233125+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "192.168.0.0/16",
"Gateway": "192.168.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"51e200a1d99e3c348b22d1231778ee417f9c092a4ac46459f505f19b142c9057": {
"Name": "tomcat01",
"EndpointID": "ea5ab2336fd3240bb43ac9defdd68c7a45fdebb49af2d51dfedeee15c74efe8e",
"MacAddress": "02:42:c0:a8:00:04",
"IPv4Address": "192.168.0.4/16",
"IPv6Address": ""
},
"77a9ca3cdc097796be715c0e6440c63db7bfee37e6a119086b140dece46a8b1c": {
"Name": "tomcat-net-02",
"EndpointID": "0f29727d7b36b8757bf9d40350d12fe3d6455297d7983b3bf01120aa2a7bd577",
"MacAddress": "02:42:c0:a8:00:03",
"IPv4Address": "192.168.0.3/16",
"IPv6Address": ""
},
"b32fc7ec5a6e1319e8e7910632c80a57eb5927f93313f1d4a074fd9023aada81": {
"Name": "tomcat-net-01",
"EndpointID": "1955652ae224c426c79771670a396750e570ce56792640faf0664eda30ab70e9",
"MacAddress": "02:42:c0:a8:00:02",
"IPv4Address": "192.168.0.2/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]
[hekai@localhost ~]$
# 发现连通之后就将tomcat01放到了mynet网络下
[hekai@localhost ~]$ docker exec -it tomcat01 ping tomcat-net-01
PING tomcat-net-01 (192.168.0.2) 56(84) bytes of data.
64 bytes from tomcat-net-01.mynet (192.168.0.2): icmp_seq=1 ttl=64 time=0.114 ms
64 bytes from tomcat-net-01.mynet (192.168.0.2): icmp_seq=2 ttl=64 time=0.102 ms
64 bytes from tomcat-net-01.mynet (192.168.0.2): icmp_seq=3 ttl=64 time=0.103 ms
^C
--- tomcat-net-01 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 38ms
rtt min/avg/max/mdev = 0.102/0.106/0.114/0.010 ms
# 显然上面tomcat01打通了，下面tomcat02没打通
[hekai@localhost ~]$ docker exec -it tomcat02 ping tomcat-net-01
ping: tomcat-net-01: Name or service not known
[hekai@localhost ~]$
结论：假设要跨网络操作别人，需要使用docker network connect连通！
实战：部署redis集群
# 创建一个网卡
# 首先清理容器
[hekai@localhost ~]$ docker rm -f $(docker ps -aq)
3e76cf8b4dac
51e200a1d99e
77a9ca3cdc09
b32fc7ec5a6e
# 创建一个redis网络
[hekai@localhost ~]$ docker network create redis --subnet 172.16.0.0/16
f82a6409056fa1b3f3a5c96d1a03b6b6195a18593552ab744169e28d625cca92
[hekai@localhost ~]$ docker network ls
NETWORK ID NAME DRIVER SCOPE
1d62f1dd42f9 bridge bridge local
d3c7ee72696e host host local
5590469f454a mynet bridge local
a8f0c9a8baa0 none null local
f82a6409056f redis bridge local
[hekai@localhost ~]$ docker network inspect redis
[
{
"Name": "redis",
"Id": "f82a6409056fa1b3f3a5c96d1a03b6b6195a18593552ab744169e28d625cca92",
"Created": "2021-03-16T14:45:22.229751861+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "172.16.0.0/16"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {},
"Options": {},
"Labels": {}
}
]
# 循环配置6个redis环境(root环境)
for port in $(seq 1 6);\
do \
mkdir -p /mydata/redis/node-${port}/conf
touch /mydata/redis/node-${port}/conf/redis.conf
cat << EOF >/mydata/redis/node-${port}/conf/redis.conf
port 6379
bind 0.0.0.0
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
cluster-announce-ip 172.16.0.1${port}
cluster-announce-port 6379
cluster-announce-bus-port 16379
appendonly yes
EOF
done
# 启动一个的集群
docker run -p 6371:6379 -p 16371:16379 --name redis-1 -v /mydata/redis/node-1/data:/data -v /mydata/redis/node-1/conf/redis.conf:/etc/redis/redis.conf -d --net redis --ip 172.16.0.11 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf
# 循环启动
for port in $(seq 2 6);\
do \
docker run -p 637${port}:6379 -p 1637${port}:16379 --name redis-${port} -v /mydata/redis/node-${port}/data:/data -v /mydata/redis/node-${port}/conf/redis.conf:/etc/redis/redis.conf -d --net redis --ip 172.16.0.1${port} redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf
done
root@X8DT6-ubuntu:/mydata/redis/node-1/conf# for port in $(seq 2 6);\
> do \
> docker run -p 637${port}:6379 -p 1637${port}:16379 --name redis-${port} -v /mydata/redis/node-${port}/data:/data -v /mydata/redis/node-${port}/conf/redis.conf:/etc/redis/redis.conf -d --net redis --ip 172.16.0.1${port} redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf
> done
ef0b410eea0a5d0b2dcf1c2b31b0a10f18eece31e57a1a4404965a671a97a195
98412d407ae720649bffe462b8f9e8a3a089001e56d3b3bf4b574331a35a9012
db977fd9874126a202374fdeeffafdabf16e047662b517fc80f10deb9e279efa
b8da639aa947337b2819d8ecd15051ca5e8922812baf5aa6a2c951d13a5cf658
623a4a69e8f97262156b78b785fbe94906e4cf254c0633c8f3280884856a836a
root@X8DT6-ubuntu:/mydata/redis/node-1/conf#
# 可以看到6个都启动了
root@X8DT6-ubuntu:/mydata/redis/node-1/conf# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
623a4a69e8f9 redis:5.0.9-alpine3.11 "docker-entrypoint.s…" 48 seconds ago Up 46 seconds 0.0.0.0:6376->6379/tcp, 0.0.0.0:16376->16379/tcp redis-6
b8da639aa947 redis:5.0.9-alpine3.11 "docker-entrypoint.s…" 50 seconds ago Up 48 seconds 0.0.0.0:6375->6379/tcp, 0.0.0.0:16375->16379/tcp redis-5
db977fd98741 redis:5.0.9-alpine3.11 "docker-entrypoint.s…" 51 seconds ago Up 49 seconds 0.0.0.0:6374->6379/tcp, 0.0.0.0:16374->16379/tcp redis-4
98412d407ae7 redis:5.0.9-alpine3.11 "docker-entrypoint.s…" 52 seconds ago Up 50 seconds 0.0.0.0:6373->6379/tcp, 0.0.0.0:16373->16379/tcp redis-3
ef0b410eea0a redis:5.0.9-alpine3.11 "docker-entrypoint.s…" 54 seconds ago Up 52 seconds 0.0.0.0:6372->6379/tcp, 0.0.0.0:16372->16379/tcp redis-2
2efafd9aed20 redis:5.0.9-alpine3.11 "docker-entrypoint.s…" About a minute ago Up About a minute 0.0.0.0:6371->6379/tcp, 0.0.0.0:16371->16379/tcp redis-1
root@X8DT6-ubuntu:/mydata/redis/node-1/conf#
# 进入redis-1
root@X8DT6-ubuntu:/mydata/redis/node-1/conf# docker exec -it redis-1 /bin/sh
/data # ls
appendonly.aof nodes.conf
/data # pwd
/data
/data #
# 创建集群
/data # redis-cli --cluster create 172.16.0.11:6379 172.16.0.12:6379 172.16.0.13:6379 172.16.0.14:6379 172.16.0.15:6379 172.16.0.16:6379 --cluster-replicas 1
>>> Performing hash slots allocation on 6 nodes...
Master[0] -> Slots 0 - 5460
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica 172.16.0.15:6379 to 172.16.0.11:6379
Adding replica 172.16.0.16:6379 to 172.16.0.12:6379
Adding replica 172.16.0.14:6379 to 172.16.0.13:6379
M: 56648fb39aa6568c1fe8c71ebede683ed6dd47e3 172.16.0.11:6379
slots:[0-5460] (5461 slots) master
M: 49255ecdc8ba9a02eb542979ea7d08aeda9e0013 172.16.0.12:6379
slots:[5461-10922] (5462 slots) master
M: a5fb7a42122ec6eedded0293dc2ffa551add96d4 172.16.0.13:6379
slots:[10923-16383] (5461 slots) master
S: b7282a9754d2079c57c8550aafb1ebd989d43a4e 172.16.0.14:6379
replicates a5fb7a42122ec6eedded0293dc2ffa551add96d4
S: fa55de0b00dc485074fd8f7496d5761c32fc1e6e 172.16.0.15:6379
replicates 56648fb39aa6568c1fe8c71ebede683ed6dd47e3
S: 698771267efc489c4a0d7b85cf5a7267a66e0cbc 172.16.0.16:6379
replicates 49255ecdc8ba9a02eb542979ea7d08aeda9e0013
Can I set the above configuration? (type 'yes' to accept): yes
>>> Nodes configuration updated
>>> Assign a different config epoch to each node
>>> Sending CLUSTER MEET messages to join the cluster
Waiting for the cluster to join
..
>>> Performing Cluster Check (using node 172.16.0.11:6379)
M: 56648fb39aa6568c1fe8c71ebede683ed6dd47e3 172.16.0.11:6379
slots:[0-5460] (5461 slots) master
1 additional replica(s)
M: 49255ecdc8ba9a02eb542979ea7d08aeda9e0013 172.16.0.12:6379
slots:[5461-10922] (5462 slots) master
1 additional replica(s)
S: fa55de0b00dc485074fd8f7496d5761c32fc1e6e 172.16.0.15:6379
slots: (0 slots) slave
replicates 56648fb39aa6568c1fe8c71ebede683ed6dd47e3
M: a5fb7a42122ec6eedded0293dc2ffa551add96d4 172.16.0.13:6379
slots:[10923-16383] (5461 slots) master
1 additional replica(s)
S: 698771267efc489c4a0d7b85cf5a7267a66e0cbc 172.16.0.16:6379
slots: (0 slots) slave
replicates 49255ecdc8ba9a02eb542979ea7d08aeda9e0013
S: b7282a9754d2079c57c8550aafb1ebd989d43a4e 172.16.0.14:6379
slots: (0 slots) slave
replicates a5fb7a42122ec6eedded0293dc2ffa551add96d4
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
# 创建完成
# 进入集群， redis-cli -c
/data # redis-cli -c
127.0.0.1:6379> cluster info
cluster_state:ok
cluster_slots_assigned:16384
cluster_slots_ok:16384
cluster_slots_pfail:0
cluster_slots_fail:0
cluster_known_nodes:6
cluster_size:3
cluster_current_epoch:6
cluster_my_epoch:1
cluster_stats_messages_ping_sent:135
cluster_stats_messages_pong_sent:124
cluster_stats_messages_sent:259
cluster_stats_messages_ping_received:119
cluster_stats_messages_pong_received:135
cluster_stats_messages_meet_received:5
cluster_stats_messages_received:259
127.0.0.1:6379> cluster nodes
49255ecdc8ba9a02eb542979ea7d08aeda9e0013 172.16.0.12:6379@16379 master - 0 1615883052570 2 connected 5461-10922
fa55de0b00dc485074fd8f7496d5761c32fc1e6e 172.16.0.15:6379@16379 slave 56648fb39aa6568c1fe8c71ebede683ed6dd47e3 0 1615883052000 5 connected
a5fb7a42122ec6eedded0293dc2ffa551add96d4 172.16.0.13:6379@16379 master - 0 1615883051000 3 connected 10923-16383
698771267efc489c4a0d7b85cf5a7267a66e0cbc 172.16.0.16:6379@16379 slave 49255ecdc8ba9a02eb542979ea7d08aeda9e0013 0 1615883051000 6 connected
56648fb39aa6568c1fe8c71ebede683ed6dd47e3 172.16.0.11:6379@16379 myself,master - 0 1615883050000 1 connected 0-5460
b7282a9754d2079c57c8550aafb1ebd989d43a4e 172.16.0.14:6379@16379 slave a5fb7a42122ec6eedded0293dc2ffa551add96d4 0 1615883051000 4 connected
127.0.0.1:6379>
# 设置两个值
127.0.0.1:6379> set a b
-> Redirected to slot [15495] located at 172.16.0.13:6379
OK
# 可以发现使用的是13来出来的，即redis-3，现在新开终端把redis-3停掉
root@X8DT6-ubuntu:/mydata/redis# docker stop redis-3
redis-3
root@X8DT6-ubuntu:/mydata/redis#
# 使用get a获得值，发现从14获得，原来是13的从机
127.0.0.1:6379> get a
-> Redirected to slot [15495] located at 172.16.0.14:6379
"b"
172.16.0.14:6379>
# 再次使用docker nodes查看，发现14变为master
172.16.0.14:6379> cluster nodes
a5fb7a42122ec6eedded0293dc2ffa551add96d4 172.16.0.13:6379@16379 master,fail - 1615883321508 1615883319000 3 connected
fa55de0b00dc485074fd8f7496d5761c32fc1e6e 172.16.0.15:6379@16379 slave 56648fb39aa6568c1fe8c71ebede683ed6dd47e3 0 1615883507410 5 connected
49255ecdc8ba9a02eb542979ea7d08aeda9e0013 172.16.0.12:6379@16379 master - 0 1615883507511 2 connected 5461-10922
698771267efc489c4a0d7b85cf5a7267a66e0cbc 172.16.0.16:6379@16379 slave 49255ecdc8ba9a02eb542979ea7d08aeda9e0013 0 1615883506406 2 connected
b7282a9754d2079c57c8550aafb1ebd989d43a4e 172.16.0.14:6379@16379 myself,master - 0 1615883506000 7 connected 10923-16383
56648fb39aa6568c1fe8c71ebede683ed6dd47e3 172.16.0.11:6379@16379 master - 0 1615883506000 1 connected 0-5460
使用了docker之后，所有的技术都会慢慢变得简单！