Docker数据卷和Docker系统管理（二）
一. 在镜像中定义卷
1. Dockerfile中定义卷的案例
VOLUME /app/data
VOLUME /app/data, /app/profiles, /app/config
VOLUME ["/app/data", "/app/profiles", "/app/config"]
注解:
- 第一行代表定义一个单 一的卷挂载在/app/data。
- 第二行代表定义了三个卷，使用逗号进行分隔
- 第三行代表定义了三个卷，只不过使用的是JSON数组
2. 获取数据卷信息案例1
（1）拉取名字叫做mongo:3.7的镜像
[root@c720120 ~]# docker image pull mongo:3.7
3.7: Pulling from library/mongo
b234f539f7a1: Pull complete
55172d420b43: Pull complete
（2）使用docker image inspect命令检查数据卷信息
[root@c720120 ~]# docker image inspect --format='{{json .ContainerConfig.Volumes}}' mongo:3.7
{"/data/configdb":{},"/data/db":{}}
（3）运行mongodb的实例
[root@c720120 ~]# docker run --name my-mongo -d mongo:3.7
0145aa8906d9e62823e091c3fbcfbce50bc27b27224f2cca456182d0dc52d9bc
（4）获取卷创建的详细信息
[root@c720120 ~]# docker inspect --format '{{json .Mounts}}' my-mongo
[{"Type":"volume","Name":"654e63e15e1366b10f661b5909bf5823e70637adf75252f4d7bdace5db3da357","Source":"/var/lib/docker/volumes/654e63e15e1366b10f661b5909bf5823e70637adf75252f4d7bdace5db3da357/_data","Destination":"/data/configdb","Driver":"local","Mode":"","RW":true,"Propagation":""},{"Type":"volume","Name":"083ed210294f7c7333d31f72123f5f2030caf0dfa56c5ba9375c590fbb9da99b","Source":"/var/lib/docker/volumes/083ed210294f7c7333d31f72123f5f2030caf0dfa56c5ba9375c590fbb9da99b/_data","Destination":"/data/db","Driver":"local","Mode":"","RW":true,"Propagation":""}]
二. 获得Docker系统的信息
1. 获得Docker基本信息
[root@c720120 ~]# docker version
Client:
Version: 18.05.0-ce
API version: 1.37
Go version: go1.9.5
Git commit: f150324
Built: Wed May 9 22:14:54 2018
OS/Arch: linux/amd64
Experimental: false
Orchestrator: swarmServer:
Engine:
Version: 18.05.0-ce
API version: 1.37 (minimum version 1.12)
Go version: go1.9.5
Git commit: f150324
Built: Wed May 9 22:18:36 2018
OS/Arch: linux/amd64
Experimental: false
2. 获得Docker的系统相关信息
[root@c720120 ~]# docker system info
Containers: 22
Running: 18
Paused: 0
Stopped: 4
Images: 55
Server Version: 18.05.0-ce
Storage Driver: overlay2
Backing Filesystem: xfs
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 773c489c9c1b21a6d78b5c538cd395416ec50f88
runc version: 4fc53a81fb7c994640722ac585fa9ca548971871
init version: 949e6fa
Security Options:
seccomp
Profile: default
Kernel Version: 3.10.0-693.el7.x86_64
Operating System: CentOS Linux 7 (Core)
OSType: linux
Architecture: x86_64
CPUs: 8
Total Memory: 7.641GiB
Name: c720120.xiodi.cn
ID: 3LFN:DY55:44IN:ZYQF:SCLG:LH7U:P2XQ:RLOP:WMMN:O7OA:C5Z5:KFC6
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Username: mike0405
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Registry Mirrors:
https://av0eyibf.mirror.aliyuncs.com/
Live Restore Enabled: false
三. 检查Docker主机的资源消耗
1. 显示当前使用的资源和多少空间可能会被回收
[root@c720120 ~]# docker system df
TYPE TOTAL ACTIVE SIZE RECLAIMABLE
Images 34 12 3.32GB 2.159GB (65%)
Containers 22 18 10.66kB 126B (1%)
Local Volumes 6 3 362.1MB 47.24MB (13%)
Build Cache
2. 如果想要显示更中详细的信息，使用-v选项。
[root@c720120 ~]# docker system df -v
Images space usage:REPOSITORY TAG IMAGE ID CREATED ago SIZE SHARED SIZE UNIQUE SiZE CONTAINERS
mongo 3.7 5651314706c2 3 hours ago ago 365.3MB 0B 365.3MB 1
my-website 1.0 26a2c3c3133d 10 hours ago ago 18MB 18MB 99B 1
<none> <none> 51e46f702575 10 hours ago ago 18MB 18MB 73B 0
hello-world latest e6de691461d8 10 hours ago ago 177.8MB 4.148MB 173.6MB 0
my-centos latest fcc50aa21ce3 11 hours ago ago 271.7MB 199.7MB 71.97MB 0
<none> <none> 48746de3c746 11 hours ago ago 902.3MB 902.3MB 0B 0
my-alpine latest dd2e0b200d6d 12 hours ago ago 5.647MB 4.148MB 1.499MB 0
centos 7 49f7960eb7e4 27 hours ago ago 199.7MB 199.7MB 0B 0
quay.io/kubernetes-for-developers/nodejs 0.2.0 593c8caeab0d 4 days ago ago 65.38MB 10.56MB 54.83MB 0
quay.io/kubernetes-for-developers/flask 0.1.0 affcedaf18ef 4 days ago ago 64.97MB 10.56MB 54.41MB 0
busybox latest 8c811b4aec35 13 days ago ago 1.146MB 0B 1.146MB 0
python 2.7 5a7d0660d94a 4 weeks ago ago 902.3MB 902.3MB 0B 0
nginx alpine ebe2c7c61055 8 weeks ago ago 18MB 18MB 0B 0
k8s.gcr.io/kube-proxy-amd64 v1.10.0 bfc21aadc7d3 2 months ago ago 97.04MB 0B 97.04MB 1
k8s.gcr.io/kube-scheduler-amd64 v1.10.0 704ba848e69a 2 months ago ago 50.39MB 1.146MB 49.25MB 1
k8s.gcr.io/kube-apiserver-amd64 v1.10.0 af20925d51a3 2 months ago ago 225MB 1.146MB 223.8MB 1
k8s.gcr.io/kube-controller-manager-amd64 v1.10.0 ad86dbed1555 2 months ago ago 147.8MB 1.146MB 146.7MB 1
k8s.gcr.io/etcd-amd64 3.1.12 52920ad46f5b 2 months ago ago 193.2MB 1.146MB 192.1MB 0
fundamentalsofdocker/ch08-web 1.0 922e085ed002 3 months ago ago 72.01MB 3.966MB 68.04MB 0
fundamentalsofdocker/ch08-db 1.0 4953d5353c17 3 months ago ago 39.46MB 4.148MB 35.31MB 0
coredns/coredns 1.0.6 d4b7466213fe 3 months ago ago 39.88MB 0B 39.88MB 2
k8s.gcr.io/kubernetes-dashboard-amd64 v1.8.3 0c60bcf89900 3 months ago ago 102.3MB 0B 102.3MB 2
registry.cn-shenzhen.aliyuncs.com/rancher_cn/heapster-amd64 v1.5.1 c41e77c31c91 3 months ago ago 75.32MB 0B 75.32MB 0
<none> <none> 65f32704f7a3 4 months ago ago 10.12MB 3.966MB 6.149MB 0
quay.io/coreos/flannel v0.10.0-amd64 f0fad859c909 4 months ago ago 44.6MB 4.148MB 40.45MB 2
registry.cn-hangzhou.aliyuncs.com/k8sth/heapster-grafana-amd64 v4.4.3 edd7018a59de 4 months ago ago 151.5MB 1.129MB 150.4MB 0
alpine 3.7 3fd9065eaf02 4 months ago ago 4.148MB 4.148MB 0B 1
k8s.gcr.io/k8s-dns-dnsmasq-nanny-amd64 1.14.8 c2ce1ffb51ed 5 months ago ago 40.95MB 0B 40.95MB 0
k8s.gcr.io/k8s-dns-sidecar-amd64 1.14.8 6f7f2dc7fab5 5 months ago ago 42.21MB 4.144MB 38.07MB 0
k8s.gcr.io/k8s-dns-kube-dns-amd64 1.14.8 80cc5ea4b547 5 months ago ago 50.46MB 4.144MB 46.31MB 0
k8s.gcr.io/pause-amd64 3.1 da86e6ba6ca1 5 months ago ago 742.5kB 0B 742.5kB 0
ubuntu 17.04 fe1cc5b91830 5 months ago ago 95.63MB 0B 95.63MB 1
registry.cn-shenzhen.aliyuncs.com/rancher_cn/heapster-influxdb-amd64 v1.3.3 577260d221db 9 months ago ago 12.55MB 1.129MB 11.42MB 0
registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64 3.0 99e59f495ffa 2 years ago ago 746.9kB 0B 746.9kB 8Containers space usage:
CONTAINER ID IMAGE COMMAND LOCAL VOLUMES SIZE CREATED ago STATUS NAMES
0145aa8906d9 mongo:3.7 "docker-entrypoint.s…" 2 0B 8 minutes ago ago Up 8 minutes my-mongo
557b896ff138 my-website:1.0 "nginx -g 'daemon of…" 0 2B 10 hours ago ago Up 10 hours my-site
f29815cfea52 ubuntu:17.04 "/bin/bash" 1 73B 10 hours ago ago Exited (1) 10 hours ago reader
02f3d25fe440 alpine "/bin/sh" 1 53B 10 hours ago ago Exited (0) 10 hours ago writer
eddd516d5c67 0c60bcf89900 "/dashboard --insecu…" 0 0B 10 hours ago ago Up 10 hours k8s_kubernetes-dashboard_kubernetes-dashboard-7b44ff9b77-87vnz_kube-system_f4b7d3c3-6354-11e8-aec8-525400da66d3_2
f628fc5261cb 0c60bcf89900 "/dashboard --insecu…" 0 0B 10 hours ago ago Exited (1) 10 hours ago k8s_kubernetes-dashboard_kubernetes-dashboard-7b44ff9b77-87vnz_kube-system_f4b7d3c3-6354-11e8-aec8-525400da66d3_1
4497d8983aa8 f0fad859c909 "/opt/bin/flanneld -…" 0 0B 10 hours ago ago Up 10 hours k8s_kube-flannel_kube-flannel-ds-jpn69_kube-system_d511775a-6350-11e8-aec8-525400da66d3_0
150eb223d319 d4b7466213fe "/coredns -conf /etc…" 0 5.27kB 10 hours ago ago Up 10 hours k8s_coredns_coredns-7997f8864c-bqjl6_kube-system_06d0a127-634e-11e8-8a76-525400da66d3_0
ce50540a5da6 d4b7466213fe "/coredns -conf /etc…" 0 5.27kB 10 hours ago ago Up 10 hours k8s_coredns_coredns-7997f8864c-7flkx_kube-system_06cd6faf-634e-11e8-8a76-525400da66d3_0
20ec466d4e7d ad86dbed1555 "kube-controller-man…" 0 0B 10 hours ago ago Up 10 hours k8s_kube-controller-manager_kube-controller-manager-c720120.xiodi.cn_kube-system_9ebd85f31a07b860847b300d2124c485_0
ccc1fa2f461b bfc21aadc7d3 "/usr/local/bin/kube…" 0 0B 10 hours ago ago Up 10 hours k8s_kube-proxy_kube-proxy-8g8xs_kube-system_06d4d12f-634e-11e8-8a76-525400da66d3_0
1e8615e3be7d f0fad859c909 "cp -f /etc/kube-fla…" 0 0B 10 hours ago ago Exited (0) 10 hours ago k8s_install-cni_kube-flannel-ds-jpn69_kube-system_d511775a-6350-11e8-aec8-525400da66d3_0
818acc639132 af20925d51a3 "kube-apiserver --re…" 0 0B 10 hours ago ago Up 10 hours k8s_kube-apiserver_kube-apiserver-c720120.xiodi.cn_kube-system_dc5a90c76fa85961f74db59b5ef2e0c1_0
68f022ef851b 704ba848e69a "kube-scheduler --ku…" 0 0B 10 hours ago ago Up 10 hours k8s_kube-scheduler_kube-scheduler-c720120.xiodi.cn_kube-system_ca4d1ecae9f198efae15156d524bb1d0_0
5184cfdeab1d registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_kube-flannel-ds-jpn69_kube-system_d511775a-6350-11e8-aec8-525400da66d3_0
f5b09907ac58 registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_kube-controller-manager-c720120.xiodi.cn_kube-system_9ebd85f31a07b860847b300d2124c485_0
94637d8b8614 registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_kube-proxy-8g8xs_kube-system_06d4d12f-634e-11e8-8a76-525400da66d3_0
f8965fe90c07 registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_coredns-7997f8864c-bqjl6_kube-system_06d0a127-634e-11e8-8a76-525400da66d3_0
09ac5692e5ac registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_kube-apiserver-c720120.xiodi.cn_kube-system_dc5a90c76fa85961f74db59b5ef2e0c1_0
c788ac0d3604 registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_kube-scheduler-c720120.xiodi.cn_kube-system_ca4d1ecae9f198efae15156d524bb1d0_0
d0ee0f4e50bb registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_kubernetes-dashboard-7b44ff9b77-87vnz_kube-system_f4b7d3c3-6354-11e8-aec8-525400da66d3_0
b8b969bf904a registry.cn-hangzhou.aliyuncs.com/k8sth/pause-amd64:3.0 "/pause" 0 0B 10 hours ago ago Up 10 hours k8s_POD_coredns-7997f8864c-7flkx_kube-system_06cd6faf-634e-11e8-8a76-525400da66d3_0Local Volumes space usage:
VOLUME NAME LINKS SIZE
docker_pets-data 0 47.24MB
my-data 0 57B
share-data 2 20B
shared-data 0 0B
654e63e15e1366b10f661b5909bf5823e70637adf75252f4d7bdace5db3da357 1 0B
083ed210294f7c7333d31f72123f5f2030caf0dfa56c5ba9375c590fbb9da99b 1 314.8MB
四. 修剪未使用的资源
1. 修剪未使用的容器
（1）修剪容器（没有在运行状态的容器）
[root@c720120 ~]# docker container prune
WARNING! This will remove all stopped containers.
Are you sure you want to continue? [y/N] y
Deleted Containers:
f29815cfea52eae2dd2e37a43d5260f5265299852f8f216ca7437b76222739c2
02f3d25fe440b709840abb055bff25ad9a90ce12acdcd2734249e5a8faff6b2d
f628fc5261cb26d15ff7d24b02abc992392c54a736f0333d9cee16cc324e24da
1e8615e3be7d24f41060319cb762a3e66b7470ab74c5af87285d6c0003f1b99eTotal reclaimed space: 126B
（2）如果在修剪时不想再次确认，可以使用-f或者—force选项。
[root@c720120 ~]# docker container prune –f
（3）如果想要移除所有的容器（包括那些在运行的），prune命令无法做到，使用以下命令.
[root@c720120 ~]# docker container rm -f $(docker container ls -aq)
2. 修剪镜像
（1）修剪镜像（没有在使用的镜像）
[root@c720120 ~]# docker image prune
（2）修剪镜像，如果不想再三确认，请使用-f或者—force选项。
[root@c720120 ~]# docker image prune –f
（3）移除所有的镜像，不仅是那些孤立的镜像
[root@c720120 ~]# docker image prune –-force –all
3. 修剪卷
（1）修剪卷（没有在使用的卷）
[root@c720120 ~]# docker volume prune
（2）修剪过滤器过滤的指定的卷
[root@c720120 ~]# docker volume prune –filter ‘label=demo’
也可以使用多个过滤器过滤卷
[root@c720120 ~]# docker volume prune –filter ‘label=demo’ –filter ‘label=test’
4. 修剪网络
[root@c720120 ~]# docker network prune
5. 执行一条命令，修剪所有的东西，包括卷，网络，容器，镜像。
[root@c720120 ~]# docker system prune
五. Docker系统事件
当docker引擎在创建，运行，停止 和移除容器和其它资源时，比如卷和网络，均会产生事件日志。
案例1：
（1）开启系统事件
[root@c720120 ~]# docker system events
（2）在Docker host的另一个终端上执行创建容器命令。
[root@c720120 ~]# docker container run --rm alpine echo "Hello World"
Hello World
（3）查看输出的事件信息
[root@c720120 ~]# docker system events
2018-06-06T09:51:45.412499798+08:00 container create 26f1bc504b5d19735558085005225a6d7ecb7bebd4c4f060c1a20c565a130cef (image=alpine, name=gifted_bassi)
2018-06-06T09:51:45.417325987+08:00 container attach 26f1bc504b5d19735558085005225a6d7ecb7bebd4c4f060c1a20c565a130cef (image=alpine, name=gifted_bassi)
2018-06-06T09:51:45.536770127+08:00 network connect 8d4ce133354ba6e3ab01684cf18b88535230647e78a6d698f1ef8d79f767b169 (container=26f1bc504b5d19735558085005225a6d7ecb7bebd4c4f060c1a20c565a130cef, name=bridge, type=bridge)
2018-06-06T09:51:46.087623064+08:00 container start 26f1bc504b5d19735558085005225a6d7ecb7bebd4c4f060c1a20c565a130cef (image=alpine, name=gifted_bassi)
2018-06-06T09:51:46.218351340+08:00 container die 26f1bc504b5d19735558085005225a6d7ecb7bebd4c4f060c1a20c565a130cef (exitCode=0, image=alpine, name=gifted_bassi)
2018-06-06T09:51:46.376077683+08:00 network disconnect 8d4ce133354ba6e3ab01684cf18b88535230647e78a6d698f1ef8d79f767b169 (container=26f1bc504b5d19735558085005225a6d7ecb7bebd4c4f060c1a20c565a130cef, name=bridge, type=bridge)
2018-06-06T09:51:46.467148084+08:00 container destroy 26f1bc504b5d19735558085005225a6d7ecb7bebd4c4f060c1a20c565a130cef (image=alpine, name=gifted_bassi)
（4）让输出事件信息按指定的格式进行输出
[root@c720120 ~]# docker system events --format 'Type={{.Type}} Image={{.Actor.Attributes.image}} Action={{.Action}}'
（5）输出信息如下
[root@c720120 ~]# docker system events --format 'Type={{.Type}} Image={{.Actor.Attributes.image}} Action={{.Action}}'
Type=container Image=alpine Action=create
Type=container Image=alpine Action=attach
Type=network Image=<no value> Action=connect
Type=container Image=alpine Action=start
Type=container Image=alpine Action=die
Type=network Image=<no value> Action=disconnect
Type=container Image=alpine Action=destroy
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- Python学习笔记（十五）用Python获取本地数据
f1 = open(r'E:\Python\Data\data1.txt') #读取data1.txt文件,使用系统默认缓冲区大小, 为了读取快点,使用缓存吧! f = open(r'E:\Pytho ...
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