docker 安装、升级、修改数据目录
1、查看系统要求
Docker 要求 CentOS 系统的内核版本高于 3.10 ,查看CentOS的内核版本。
uname -a
2、删除旧版本
yum remove docker docker-common docker-selinux docker-engine
3、安装需要的软件包
yum-util 提供yum-config-manager功能，另外两个是devicemapper驱动依赖的
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
4、设置Docker yum源
# 使用官方源
sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
# 使用阿里源
sudo yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
sudo sed -i 's+download.docker.com+mirrors.aliyun.com/docker-ce+' /etc/yum.repos.d/docker-ce.repo
5、查看所有仓库中所有docker版本
可以查看所有仓库中所有docker版本,并选择特定的版本安装。
yum list docker-ce --showduplicates | sort -r
6、安装docker
sudo yum install docker-ce
由于repo中默认只开启stable仓库，故这里安装的是最新稳18.03.0.ce-1.el7.centos。
如果要安装特定版本：
sudo yum install docker-ce-18.06.1.ce
7、启动
设置为开机启动
systemctl enable docker
启动
systemctl start docker
查看启动状态
systemctl status docker
如果出现异常
$ systemctl start docker
A dependency job for docker.service failed. See 'journalctl -xe' for details.
查看报错信息
Mar 03 11:19:47 master1 systemd[1]: Starting containerd container runtime...
-- Subject: Unit containerd.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit containerd.service has begun starting up.
Mar 03 11:19:47 master1 systemd[104332]: Failed at step LIMITS spawning /sbin/modprobe: Operation not permitted
-- Subject: Process /sbin/modprobe could not be executed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- The process /sbin/modprobe could not be executed and failed.
--
-- The error number returned by this process is 1.
Mar 03 11:19:47 master1 systemd[104335]: Failed at step LIMITS spawning /usr/bin/containerd: Operation not permitted
-- Subject: Process /usr/bin/containerd could not be executed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- The process /usr/bin/containerd could not be executed and failed.
解决方案：
查看open files的值，修改/usr/lib/systemd/system/docker.service和/usr/lib/systemd/system/containerd.service（如下图），启动即可
$ ulimit -a
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 23056
max locked memory (kbytes, -l) 64
max memory size (kbytes, -m) unlimited
open files (-n) 654350
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) 23056
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited
$ vim /usr/lib/systemd/system/docker.service
...
# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNOFILE=654349 # 注意这里
LimitNPROC=23057
LimitCORE=infinity
# Comment TasksMax if your systemd version does not supports it.
...
$ vim /usr/lib/systemd/system/containerd.service
...
# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNOFILE=654349 # 注意这里
LimitNPROC=23057
LimitCORE=infinity
# Comment TasksMax if your systemd version does not support it.
...
查看版本
docker version
8、修改数据目录
方式一
# 将下面的json拷贝纸docker启动目录
$ vim /etc/docker/daemon.json
{
"data-root": "/data/docker"
}
方式二
查看docker当前信息
$ docker info
Client:
Context: default
Debug Mode: false
Plugins:
app: Docker App (Docker Inc., v0.9.1-beta3)
buildx: Docker Buildx (Docker Inc., v0.8.2-docker)
scan: Docker Scan (Docker Inc., v0.17.0)
Server:
Containers: 40
Running: 15
Paused: 0
Stopped: 25
Images: 91
Server Version: 20.10.17
Storage Driver: overlay2
Backing Filesystem: extfs
Supports d_type: true
Native Overlay Diff: true
userxattr: false
Logging Driver: json-file
Cgroup Driver: systemd
Cgroup Version: 1
Plugins:
Volume: local
Network: bridge host ipvlan macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
Swarm: inactive
Runtimes: io.containerd.runc.v2 io.containerd.runtime.v1.linux runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 10c12954828e7c7c9b6e0ea9b0c02b01407d3ae1
runc version: v1.1.2-0-ga916309f
init version: de40ad0
Security Options:
seccomp
Profile: default
Kernel Version: 3.10.0-1160.71.1.el7.x86_64
Operating System: CentOS Linux 7 (Core)
OSType: linux
Architecture: x86_64
CPUs: 16
Total Memory: 15.5GiB
Name: master1
ID: 3WQC:QCTB:I5D4:2ZWL:VBSH:6GWQ:4W2G:BTK2:XSEY:PDXG:BQAI:ZB6D
Docker Root Dir: /data/docker # 这里是数据目录的位置，我因为已经更改过，原位置为/var/lib/docker
Debug Mode: false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Registry Mirrors:
https://x6u7jv2l.mirror.aliyuncs.com/
Live Restore Enabled: false
9、停止docker服务
$ systemctl stop docker
10、修改docker服务启动文件
vi /usr/lib/systemd/system/docker.service
ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock --graph=/data/docker
11、复制原有数据，若无数据，可跳过此步骤
$ cp -rf /var/lib/docker/* /data/docker/
12、重新加载配置文件并启动
$ systemctl daemon-reload
$ systemctl start docker
最后执行步骤8，查看是否已启动
