docker devicemapper 扩容
查看当前大小: 100G
$ ls -lh /var/lib/docker/devicemapper/devicemapper/
total 82G
-rw------- 1 root root 100G Dec 4 14:06 data
-rw------- 1 root root 2.0G Dec 4 14:05 metadata
扩容到200G
$ truncate -s 200G /var/lib/docker/devicemapper/devicemapper/data
查看扩容后磁盘文件大小(内存中大小暂未改变)
$ ls -lh /var/lib/docker/devicemapper/devicemapper/
total 82G
-rw------- 1 root root 200G Dec 4 14:07 data
-rw------- 1 root root 2.0G Dec 4 14:07 metadata
reload
从命令行调用区块设备控制程序
$ echo $[ $(sudo blockdev --getsize64 /dev/loop0) / 1024 / 1024 / 1024 ]
100
losetup用来将loopdevice与档案或blockdevice联结、分离.以及查询loopdevice目前的状况,如只给定loop_device的参数.则秀出loopdevice目前的状况
$ losetup -c /dev/loop0
$ echo $[ $(sudo blockdev --getsize64 /dev/loop0) / 1024 / 1024 / 1024 ]
200
Reload the devicemapper thin pool
$ dmsetup status | grep ' thin-pool ' | awk -F ': ' {'print $1'}
docker-252:0-5637144768-pool
$ dmsetup table docker-252:0-5637144768-pool
0 209715200 thin-pool 7:1 7:0 128 32768 1 skip_block_zeroing
$ dmsetup suspend docker-252:0-5637144768-pool
$ dmsetup reload docker-252:0-5637144768-pool --table '0 419430400 thin-pool 7:1 7:0 128 32768 1 skip_block_zeroing'
$ dmsetup resume docker-252:0-5637144768-pool
扩容完成查看效果(200G)
$ docker info
Containers: 21
Running: 20
Paused: 0
Stopped: 1
Images: 118
Server Version: 17.05.0-ce
Storage Driver: devicemapper
Pool Name: docker-252:0-5637144768-pool
Pool Blocksize: 65.54kB
Base Device Size: 64.42GB
Backing Filesystem: xfs
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 87.43GB
Data Space Total: 214.7GB
Data Space Available: 127.3GB
Metadata Space Used: 99.05MB
Metadata Space Total: 2.147GB
Metadata Space Available: 2.048GB
Thin Pool Minimum Free Space: 21.47GB
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