docker 扩容

1.查看存储引擎：
# docker info
需要是 devicemapper
Images: 46
Storage Driver: devicemapper
2.新建一个 容器
# docker run -itd -p 5001:5001 --name=centos7 centos
3.查看ip
# docker inspect centos7 | grep -i add
4.ssh 连接 并查看 df
5.扩容脚本
# vim dynamic_modify_docker_disk.sh
#!/bin/bash
#This script is dynamic modify docker container disk
#Author Deng Lei
if [ -z $1 ] || [ -z $2 ]; then
    echo "Usage: container_name increase_capacity"
    echo "Example: I want increase 11G to test"
    echo "The command is:   sh `basename $0` test 11"
    exit 1
                                                                                                                                                        fi
if [ `docker inspect $1 &>>/dev/null &&  echo 0 || echo 1` -eq 1 ];then
    echo "The container $1 is no exist!"
    exit 1
fi
container_id=`docker inspect -f '{{ .Id }}' $1`
now_disk=`dmsetup table /dev/mapper/docker-*-$container_id|awk '{print $2}'`
disk=$(($2*1024*1024*1024/512))
if [ $disk -lt $now_disk ];then
    echo "I can't shink container $1 from $(($now_disk*512/1024/1024/1024))G to ${2}G!I only modify contanier increase disk!"
    exit 1
fi
dmsetup table /dev/mapper/docker-*-$container_id|sed "s/0 [0-9]* thin/0 $disk thin/"|dmsetup load /dev/mapper/docker-*-$container_id
dmsetup resume /dev/mapper/docker-*-$container_id
resize2fs /dev/mapper/docker-*-$container_id
if [ $? -eq 0 ];then
    echo "dynamic container $1 disk to ${2}G is success!"
else
    echo "dynamic container $1 disk to ${2}G is fail!"
fi

运行脚本：
sh dynamic_modify_docker_disk.sh centos7  20
再次查看 df