docker数据卷

容器如何与宿主机之间进行数据共享

容器如何和宿主机进行数据共享

数据卷是一个供容器使用的特殊的目录，在容器中，和宿主机的目录进行映射，主机和宿主机之间都可以对目录中的文件进行修改，双方同步生效，对镜像也没有影响，宿主机到容器实现数据迁移

宿主机的目录和容器中目录进行挂载（映射关系）

[root@docker1 ~]# docker run -itd  --name test1 -v /opt/test1:/opt/test nginx:1.22.0 /bin/bash
a335cb5c1211cebe0c06ffaa64de73f3771a17743958d23b273117aedd2e2df4
[root@docker1 ~]# cd /opt/test1/
[root@docker1 test1]# ls
[root@docker1 test1]# echo 123 > 123.txt
[root@docker1 test1]# docker exec -it test1 bash
root@a335cb5c1211:/# 
root@a335cb5c1211:/# cd /opt/test/
root@a335cb5c1211:/opt/test# cat 123.txt 
123
root@a335cb5c1211:/opt/test# 

加上ro（容器只能读）

[root@docker1 test1]# docker run -itd --name test2 -v /opt/test2:/opt/test1:ro nginx:1.22.0 /bin/bash
68390c72c3169ab251db210f605fa277516e61b373477ac8bf831f624e39aa17
[root@docker1 test1]# cd /opt/test2/
[root@docker1 test2]# echo 123 > 1.txt
[root@docker1 test2]# docker exec -it test
test1  test2  
[root@docker1 test2]# docker exec -it test2 bash
root@68390c72c316:/# cd /opt/test1/
root@68390c72c316:/opt/test1# cat 1.txt 
123
root@68390c72c316:/opt/test1# echo 1 > 1.txt   
bash: 1.txt: Read-only file system
root@68390c72c316:/opt/test1# 

容器和容器之间实现数据共享

test1 test2 可以有一个或者多个映射目录，实现数据互传，数据同步

创建挂载卷容器
docker run -itd --name test3 -v /opt/data1 -v /opt/data2 nginx:1.22.0 /bin/bash

创建容器使用挂载卷
docker run -itd --volumes-from test3 --name test4 nginx:1.22.0 /bin/bash

[root@docker1 test2]# docker ps -a
CONTAINER ID   IMAGE          COMMAND                  CREATED          STATUS          PORTS     NAMES
583801dc6745   nginx:1.22.0   "/docker-entrypoint.…"   8 seconds ago    Up 8 seconds    80/tcp    test4
8dc4ec61f469   nginx:1.22.0   "/docker-entrypoint.…"   2 minutes ago    Up 2 minutes    80/tcp    test3
68390c72c316   nginx:1.22.0   "/docker-entrypoint.…"   8 minutes ago    Up 8 minutes    80/tcp    test2
a335cb5c1211   nginx:1.22.0   "/docker-entrypoint.…"   11 minutes ago   Up 11 minutes   80/tcp    test1
[root@docker1 test2]# docker exec -it test4 bash
root@583801dc6745:/# cd /opt/
root@583801dc6745:/opt# sl
bash: sl: command not found
root@583801dc6745:/opt# ls
data1  data2
root@583801dc6745:/opt# cd data2
root@583801dc6745:/opt/data2# echo 1 > 12




[root@docker1 ~]# docker exec -it test3 bash
root@8dc4ec61f469:/# cd /opt/
root@8dc4ec61f469:/opt# ls
data1  data2
root@8dc4ec61f469:/opt# cd data  
bash: cd: data: No such file or directory
root@8dc4ec61f469:/opt# cd data1/
root@8dc4ec61f469:/opt/data1# ls
root@8dc4ec61f469:/opt/data1# cd .. 
root@8dc4ec61f469:/opt# cd data2
root@8dc4ec61f469:/opt/data2# ls
12

容器互联

两个容器之间实现网络通信

方法一：

[root@docker1 test2]# docker run -itd --name host1 -P centos:7 /bin/bash
61f66eb7446be8d9e4bd16d25c8e9c2d3987f687866d4c2c859f6615f8e6e97b
[root@docker1 test2]# docker run -itd --name host2 -P --link host1:host2 centos:7 /bin/bash
e0040bcc515510f809dd2d338de1dac74867d5be1ecacce6cbe3573f7b602a69
[root@docker1 test2]# docker exec -it host1 bash
[root@61f66eb7446b /]# yum install -y net-tools 
[root@docker1 ~]# docker exec -it host2 bash
[root@e0040bcc5155 /]# yum install -y net-tools 

方法二：

先创建一个网段
[root@docker1 ~]# docker network create --subnet 190.0.0.0/16 --opt "com.docker.network.bridge.name"="docker" mydocker
ddd311276e782cefee5f0ab62885a72b64f292f03be8e8a93ea3d0a09fc75951
[root@docker1 ~]# ifconfig 
docker: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        inet 190.0.0.1  netmask 255.255.0.0  broadcast 190.0.255.255
        ether 02:42:76:bb:56:6e  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 0 overruns 0  carrier 0  collisions 0

创建两个容器，指定网段
[root@docker1 ~]# docker run -itd --name xiaobu1 -P --network mydocker centos:7 /bin/bash
435604edf1e3501db53268574adcf62cff1daae59df13b92de6ad81efd1d4483
[root@docker1 ~]# docker run -itd --name xiaobu2 -P --network mydocker centos:7 /bin/bash
1831431ae1fba8e12fcbf1cd0f88853431d74f06b72e87e58ad73d95e9ea9579

通过ping的方式
[root@docker1 ~]# docker exec -it xiaobu1 bash
[root@435604edf1e3 /]# ping xiaobu2      
PING xiaobu2 (190.0.0.3) 56(84) bytes of data.
64 bytes from xiaobu2.mydocker (190.0.0.3): icmp_seq=1 ttl=64 time=0.030 ms
64 bytes from xiaobu2.mydocker (190.0.0.3): icmp_seq=2 ttl=64 time=0.045 ms
64 bytes from xiaobu2.mydocker (190.0.0.3): icmp_seq=3 ttl=64 time=0.047 ms
64 bytes from xiaobu2.mydocker (190.0.0.3): icmp_seq=4 ttl=64 time=0.048 ms
64 bytes from xiaobu2.mydocker (190.0.0.3): icmp_seq=5 ttl=64 time=0.047 ms
^C
--- xiaobu2 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4000ms
rtt min/avg/max/mdev = 0.030/0.043/0.048/0.009 ms

[root@docker1 test2]# docker exec -it xiaobu2 bash
[root@1831431ae1fb /]# ping xiaobu1
PING xiaobu1 (190.0.0.2) 56(84) bytes of data.
64 bytes from xiaobu1.mydocker (190.0.0.2): icmp_seq=1 ttl=64 time=0.072 ms
64 bytes from xiaobu1.mydocker (190.0.0.2): icmp_seq=2 ttl=64 time=0.050 ms
64 bytes from xiaobu1.mydocker (190.0.0.2): icmp_seq=3 ttl=64 time=0.048 ms
^C
--- xiaobu1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 0.048/0.056/0.072/0.013 ms