@chengjk

You can read the guide below to setup your block storage:

https://www.digitalocean.com/community/tutorials/how-to-use-block-storage-on-digitalocean#preparing-volumes-for-use-in-linux

From there, you have a few options: symlink directories or mount them. But before you do anything below, make sure you backup backup backup. Once you rm -rf a directory, it’s gone and it’s not coming back.

1). Symlink Directories

Since /home/dokku is the current home directory, you would simply create a new directory on the block storage device:

mkdir -p /path/to/block/device/dokku

Copy current data from /home/dokku to the new location:

cp -R /home/dokku/* /path/to/block/storage/dokku

NOTE: Before the next step, make sure all data was successfully copied to the new directory!

Now delete the current directory and create a symlink to the new one:

sudo rm -rf /home/dokku
sudo ln -s /home/dokku /path/to/block/storage/dokku

2). Mount Directories

mkdir -p /path/to/block/device/dokku

Copy current data from /home/dokku to the new location:

cp -R /home/dokku/* /path/to/block/storage/dokku

NOTE: Before the next step, make sure all data was successfully copied to the new directory!

Now delete the current directory and mount to the new one:

sudo rm -rf /home/dokku
sudo mount --bind /home/dokku /path/to/block/storage/dokku

Now this is NOT permanent, so you need to modify fstab and place an entry in there as well:

nano /etc/fstab

and paste in:

/home/dokku   /path/to/block/storage/dokku   none    bind