Working with LVM for your Docker Container (file device)

[exa-Seyidagha]

Exasol on Docker has multiple options when it comes to data storage. You can either use a partition/disk or a storage file located in a specific location on the Docker host. The examples below all use a file system to store the dev.1 file which is used by EXAStorage.

Create a logical volume

1. Add a physical device to LVM:

$ pvcreate /dev/vda

2. Create a volume group:

$ vgcreate VG1 /dev/vda

3. Create a logical volume:

$ lvcreate --size 30G VG1

4. Add a filesystem:

$ mkfs.ext4 /dev/VG1/lvol0

5. Mount:

$ mount /dev/VG1/lvol0 /mnt/

5.1. or Mount Permanently by adding it to /etc/fstab:

$ echo 

When you reach the limit of your storage device you can increase its capacity by executing the commands below:

Increase the size of the physical device

1. Increase the size of the physical device:

$ pvresize /dev/vda

2. Extend logical volume and resize the file system:

$ lvextend -r -L +20GB /dev/VG1/lvol0

2.1. or if lvextend was executed without -r:

$ resize2fs /dev/VG1/lvol0

 

If you prefer using a storage file, you can do the following:

Add a disk to an existing volume group and logical volume

1. Add physical device to LVM:

$ pvcreate /dev/vdb

2. Extend volume group:

$ vgextend VG1 /dev/vdb

3. Extend logical volume and resize FS:

$ lvextend -r -L+100G /dev/VG1/lvol0

3.1. or if lvextend was executed without -r:

$ resize2fs /dev/VG1/lvol0

4. Enter container and enlarge file device:

$ truncate --size=+10GB /exa/data/storage/dev.1
$ cshdd --enlarge -n 11 -h /exa/data/storage/dev.1