Docker系列2：Docker安裝配置與基本使用

一、基礎(chǔ)環(huán)境介紹

1、基礎(chǔ)軟硬件環(huán)境介紹

• 需要64位的CPU

• linux內(nèi)核版本3.10及以上

• 內(nèi)核支持cggroups 和 namespace

• 系統(tǒng)版本為CentOS7.4【centos6也可安裝，但是不穩(wěn)定】

• Docker版本為18.06
  

• K8S版本為1.16 【k8s版本必須和docker版本兼容】

2、查看k8s與docker版本的對(duì)應(yīng)關(guān)系

第一步：登錄github

https://github.com/kubernetes/kubernetes/releases

第二步：查看指定版本k8s的CHANGELOG文件

第三步：搜索docker version，查看支持的docker版本

3、配置yum源

1）用阿里云的鏡像即可，路徑為 https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/7/x86_64/stable/Packages/，如下

2）配置yum源

[root@host1?~]#?cat?/etc/yum.repos.d/docker.repo?
[docker]
name=aliyun?docker?repo
enabled=1
gpgcheck=0
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/7/x86_64/stable/

查看是否配置成功

[root@host1?~]#?yum?repolist
Loaded?plugins:?fastestmirror
Loading?mirror?speeds?from?cached?hostfile
?*?base:?mirror.bit.edu.cn
?*?extras:?mirrors.huaweicloud.com
?*?updates:?mirrors.huaweicloud.com
repo?id???????????????????????????????????????repo?name????????????????????????????????????????status
docker????????????????????????????????????????aliyun?docker?repo???????????????????????????????????58
base/7/x86_64?????????????????????????????????CentOS-7?-?Base??????????????????????????????????10,097
extras/7/x86_64???????????????????????????????CentOS-7?-?Extras???????????????????????????????????307
updates/7/x86_64??????????????????????????????CentOS-7?-?Updates??????????????????????????????????997

二、安裝配置docker

1、安裝docker 18.06.0

[root@host1?~]#?yum?install?docker-ce-18.06.0.ce

2、創(chuàng)建json文件加速docker鏡像下載速度

[root@host1?~]#?mkdir?/etc/docker
[root@host1?~]#?cat?/etc/docker/daemon.json
{
????"registry-mirrors":?["https://registry.docker-cn.com"]
}

3、啟動(dòng)服務(wù)

[root@host1?~]#?systemctl?start?docker
[root@host1?~]#?systemctl?status?docker

看下docker版本

[root@host1?~]#?docker?--version
Docker?version?18.06.0-ce,?build?0ffa825

查看docker信息

[root@host1?~]#?docker?info

三、關(guān)于鏡像的操作

1、關(guān)于防火墻問(wèn)題

docker是需要啟動(dòng)iptables這個(gè)服務(wù)的，但是在centos7中，默認(rèn)是用firewalld來(lái)管理，而不是iptables，所以可能會(huì)導(dǎo)致docer使用有問(wèn)題，因?yàn)樾枰猧ptables做端口映射?？梢杂萌缦碌姆绞絹?lái)解決

[root@host1?~]#?systemctl?disable?firewalld??????????^C
[root@host1?~]#?yum?install?iptables-services?-y???????^C
[root@host1?~]#?systemctl?enable?iptables?????????????^C

2、查看本地的鏡像

[root@host1?~]#?docker?images
REPOSITORY??????????TAG?????????????????IMAGE?ID????????????CREATED?????????????SIZE

3、搜索鏡像，如搜索nginx鏡像

[root@host1?~]#?docker?search?nginx

從上面的search的結(jié)果可以看到，有些搜索出來(lái)的結(jié)果就是一個(gè)內(nèi)容，而有些結(jié)果是用斜杠分割的

• 沒(méi)有斜杠分隔的，我們稱之為頂級(jí)倉(cāng)庫(kù)，一般就是官方的

• 有分隔的稱之為：用戶倉(cāng)庫(kù)或者像倉(cāng)庫(kù)，一般就是用戶自己注冊(cè)賬號(hào)，然后做個(gè)倉(cāng)庫(kù)，并放一些鏡像給別人用。

4、拉去幾個(gè)鏡像

1）拉取nginx鏡像，為節(jié)省帶寬，此處選alpine版本

[root@host1?~]#?docker?image?pull?nginx:1.14-alpine
1.14-alpine:?Pulling?from?library/nginx
bdf0201b3a05:?Pull?complete?
3d0a573c81ed:?Pull?complete?
8129faeb2eb6:?Pull?complete?
3dc99f571daf:?Pull?complete?
Digest:?sha256:485b610fefec7ff6c463ced9623314a04ed67e3945b9c08d7e53a47f6d108dc7
Status:?Downloaded?newer?image?for?nginx:1.14-alpine

2）拉取busybox鏡像

[root@host1?~]#?docker?image?pull?busybox
Using?default?tag:?latest
latest:?Pulling?from?library/busybox
322973677ef5:?Pull?complete?
Digest:?sha256:1828edd60c5efd34b2bf5dd3282ec0cc04d47b2ff9caa0b6d4f07a21d1c08084
Status:?Downloaded?newer?image?for?busybox:latest

3）查看本地已經(jīng)下載的鏡像

[root@host1?~]#?docker?image?ls
REPOSITORY??????????TAG?????????????????IMAGE?ID????????????CREATED?????????????SIZE
busybox?????????????latest??????????????b534869c81f0????????2?weeks?ago?????????1.22MB
nginx???????????????1.14-alpine?????????8a2fb25a19f5????????8?months?ago????????16MB

• REPOSITORY：倉(cāng)庫(kù)名稱

• TAG：標(biāo)簽

• IMAGE ID：唯一ID值

• CREATED：什么時(shí)間創(chuàng)建的

• SIZE：大小

4）查看鏡像的詳細(xì)信息

[root@host1?~]#?docker?image?ls?--no-trunc
REPOSITORY??????????TAG?????????????????IMAGE?ID??????????????????????????????????????????????????????????????????CREATED?????????????SIZE
busybox?????????????latest??????????????sha256:b534869c81f05ce6fbbdd3a3293e64fd032e059ab4b28a0e0d5b485cf904be4b???2?weeks?ago?????????1.22MB
nginx???????????????1.14-alpine?????????sha256:8a2fb25a19f5dc1528b7a3fabe8b3145ff57fe10e4f1edac6c718a3cf4aa4b73???8?months?ago????????16MB

四、關(guān)于容器的操作

1、容器操作包括如下

• 啟動(dòng)容器：start

• 停止容器：stop

• 強(qiáng)制停止：kill

• 創(chuàng)建后直接啟動(dòng)容器：run

• 暫停容器：pause

• 取消暫停（繼續(xù)運(yùn)行）容器：unpause

• 也可以列出來(lái)全部的容器：docker ps或docker container ls

2、啟動(dòng)容器操作

啟動(dòng)容器用run命令，包括如下參數(shù)

• -t：這里是指定一個(gè)終端，如果沒(méi)有終端，是無(wú)法登陸這個(gè)容器的

• -i, --interactive：如果想用交互式訪問(wèn)，就需要用這個(gè)選項(xiàng)

• --name string：這里是指定容器的名字

• --rm：當(dāng)容器停止的時(shí)候，自動(dòng)刪除容器對(duì)象

• -d, --detach ：讓當(dāng)前的這個(gè)容器工作在后臺(tái)

• --network string ：指定容器加入到哪個(gè)網(wǎng)絡(luò)，如果不加的話，默認(rèn)是一個(gè)bridge網(wǎng)絡(luò)

3、基于busybox啟動(dòng)容器

[root@host1?~]#?docker?run?--name?bbox?-it?busybox
/?#

• 此時(shí)就啟動(dòng)了容器，同時(shí)進(jìn)入了容器的shell中

此時(shí)，在其他的終端可以看到busybox容器已經(jīng)啟動(dòng)了

[root@host1?~]#?docker?ps
CONTAINER?ID????????IMAGE???????????????COMMAND?????????????CREATED??????????????STATUS??????????????PORTS???????????????NAMES
dc696a322096????????busybox?????????????"sh"????????????????About?a?minute?ago???Up?About?a?minute???????????????????????bbox

查看busybox容器中的信息可以看到此時(shí)id為1的進(jìn)程是sh而不是init

/?#?ps
PID???USER?????TIME??COMMAND
????1?root??????0:00?sh
????6?root??????0:00?ps

在busybox容器中模擬apache

/?#?mkdir?/data/html?-p
/?#?echo?"test?page">>/data/html/index.html
/?#?
/?#?httpd?-f?-h?/data/html/

也可以在bash中查看一下容器的詳細(xì)信息

[root@host1?~]#?docker?inspect?bbox2?|?grep?IPAddress
????????????"SecondaryIPAddresses":?null,
????????????"IPAddress":?"172.17.0.3",
????????????????????"IPAddress":?"172.17.0.3",

• 可看到這個(gè)容器的地址是172.16.0.3
  

其實(shí)在安裝了docker以后，系統(tǒng)默認(rèn)生成一個(gè)虛擬網(wǎng)卡docker0，物理機(jī)就是用docker0和虛擬機(jī)通信的

[root@host1?~]#?ip?addr?
1:?lo:?<LOOPBACK,UP,LOWER_UP>?mtu?65536?qdisc?noqueue?state?UNKNOWN?group?default?qlen?1000
2:?ens33:?<BROADCAST,MULTICAST,UP,LOWER_UP>?mtu?1500?qdisc?pfifo_fast?state?UP?group?default?qlen?1000
3:?ens37:?<BROADCAST,MULTICAST,UP,LOWER_UP>?mtu?1500?qdisc?pfifo_fast?state?UP?group?default?qlen?1000
4:?docker0:?<BROADCAST,MULTICAST,UP,LOWER_UP>?mtu?1500?qdisc?noqueue?state?UP?group?default?
????link/ether?02:42:d5:cc:54:6d?brd?ff:ff:ff:ff:ff:ff
????inet?172.17.0.1/16?brd?172.17.255.255?scope?global?docker0
???????valid_lft?forever?preferred_lft?forever
????inet6?fe80::42:d5ff:fecc:546d/64?scope?link?
???????valid_lft?forever?preferred_lft?forever
6:?veth96dc278@if5:?<BROADCAST,MULTICAST,UP,LOWER_UP>?mtu?1500?qdisc?noqueue?master?docker0?state?UP?group?default?
10:?veth793182e@if9:?<BROADCAST,MULTICAST,UP,LOWER_UP>?mtu?1500?qdisc?noqueue?master?docker0?state?UP?group?default

• docker0的地址是172.17.0.1

在物理機(jī)用curl可以訪問(wèn)容器中的apache

[root@host1?~]#?curl?172.17.0.3
test?page

3、停止容器與重新啟動(dòng)容器

執(zhí)行exit就可以退出容器

/?#?exit
[root@host1?~]#

退出容器后，容器只是停止了，但是依然存在

• docker ps：查看正在運(yùn)行的容器

• docker ps -a：查看全部的容器，包括已經(jīng)停止的

[root@host1?~]#?docker?ps
CONTAINER?ID????????IMAGE???????????????COMMAND?????????????CREATED?????????????STATUS??????????????PORTS???????????????NAMES

[root@host1?~]#?docker?ps?-a
CONTAINER?ID????????IMAGE???????????????COMMAND?????????????CREATED?????????????STATUS???????????????????????PORTS???????????????NAMES
dc696a322096????????busybox?????????????"sh"????????????????2?hours?ago?????????Up?2?hours???????????????????????????????????????bbox

重啟啟動(dòng)這個(gè)停止的容器，用start命令，可能用兩個(gè)選項(xiàng)

• -i：交互模式
  

• -a：附加到終端上

[root@host1?~]#?docker?start?-i?-a?bbox

4、刪除已經(jīng)停止的容器

[root@host1?~]#?docker?rm?bbox
bbox
[root@host1?~]#?docker?ps?-a
CONTAINER?ID????????IMAGE???????????????COMMAND?????????????CREATED?????????????STATUS???????????????????????PORTS???????????????NAMES

在創(chuàng)建容器的時(shí)候加入rm選項(xiàng)，可以實(shí)現(xiàn)當(dāng)容器停止的時(shí)候，自動(dòng)刪除

[root@host1?~]#?docker?run?--rm?-it?--name?bbox2?busybox
/?#?
/?#?exit

[root@host1?~]#?docker?ps?-a
CONTAINER?ID????????IMAGE???????????????COMMAND?????????????CREATED?????????????STATUS??????????????PORTS???????????????NAMES

在刪除容器時(shí)候可以指定名稱來(lái)刪除，也可以指定容器的ID來(lái)刪除

• 在指定ID的時(shí)候，不需要寫(xiě)全部的ID內(nèi)容，寫(xiě)開(kāi)頭的一部分即可
  

[root@host1?~]#?docker?ps?-a
CONTAINER?ID????????IMAGE???????????????COMMAND?????????????CREATED?????????????STATUS????????????????????PORTS???????????????NAMES
9c2d1bbe32e8????????busybox?????????????"sh"????????????????3?seconds?ago???????Exited?(0)?1?second?ago???????????????????????bbox

[root@host1?~]#?docker?rm?9c2d
9c2d

[root@host1?~]#?docker?ps?-a
CONTAINER?ID????????IMAGE???????????????COMMAND?????????????CREATED?????????????STATUS??????????????PORTS???????????????NAMES

下面的命令可以一次將所有已經(jīng)停止的容器刪除

[root@host1?~]#?docker?rm?$(docker?ps?-a?-q)

5、刪除鏡像、導(dǎo)出鏡像、導(dǎo)入鏡像

• rmi：刪除本地的鏡像
  

• load：導(dǎo)入鏡像文件
  

• save：導(dǎo)出鏡像文件

查看當(dāng)前有哪些鏡像

[root@host1?~]#?docker?image?ls
REPOSITORY??????????TAG?????????????????IMAGE?ID????????????CREATED?????????????SIZE
busybox?????????????latest??????????????b534869c81f0????????2?weeks?ago?????????1.22MB
nginx???????????????1.14-alpine?????????8a2fb25a19f5????????8?months?ago????????16MB

導(dǎo)出busybox的鏡像到tmp下

[root@host1?~]#?docker?save?busybox:latest>/tmp/busybox-latest.tar.gz
[root@host1?~]#?ls?/tmp/
busybox-latest.tar.gz

刪除本地的busybox鏡像

[root@host1?~]#?docker?rmi?b53
Untagged:?busybox:latest
Untagged:?busybox@sha256:1828edd60c5efd34b2bf5dd3282ec0cc04d47b2ff9caa0b6d4f07a21d1c08084
Deleted:?sha256:b534869c81f05ce6fbbdd3a3293e64fd032e059ab4b28a0e0d5b485cf904be4b
Deleted:?sha256:eac247cb7af5edc34d3620e8bce653d4af7d4e3a0427d487a97530c7fac0b841

[root@host1?~]#?docker?image?ls
REPOSITORY??????????TAG?????????????????IMAGE?ID????????????CREATED?????????????SIZE
nginx???????????????1.14-alpine?????????8a2fb25a19f5????????8?months?ago????????16MB

從tmp下導(dǎo)入鏡像文件

[root@host1?~]#?docker?load</tmp/busybox-latest.tar.gz?
eac247cb7af5:?Loading?layer?[==================================================>]??1.437MB/1.437MB
Loaded?image:?busybox:latest

[root@host1?~]#?docker?image?ls
REPOSITORY??????????TAG?????????????????IMAGE?ID????????????CREATED?????????????SIZE
busybox?????????????latest??????????????b534869c81f0????????2?weeks?ago?????????1.22MB
nginx???????????????1.14-alpine?????????8a2fb25a19f5????????8?months?ago????????16MB