Solved difference between ZFS datatset with folder in zfs pool ?

[fff2024g]

Dear all :
i used command create a folder in same zfs pool in below .
zfs create p200/external_disk
mdkir /p200/external_disk

1. question is what difference about zfs create p200/external_disk dataset with mkdir /p200/external_disk in same pool p200 ? looks like those all are directory .
i know the dataset is a data collection. folder is a directory.
i create it in same pool p200.
2. can we create directory in zfs pool ? or we only use zfs create command to create dataset ,vol in the zfs pool ? what is best operation ?
3. usage of normal directory in zfs pool ?

thanks.

 

[fff2024g]

DEar all:
maybe i known my question . we can create folder in zfs pool anywhere. the folder was belongs dataset . dataset can include more folder , but folder don't include dataset . we can mount other disk space to the folder , we can't mount other disk space to the dataset ... is that right ?

 

[Lamia]

the folder (i.e. snapdir) *stores* datasets.
Folder can include more datasets , but a dataset don't include folder

 

[FleurNoire]

When you create a pool, ZFS automatically creates a root dataset, in your case p200, which is mounted under /p200 by default. If you were to create only subdirectories in this directory, you would be missing one of the best features of ZFS, snapshots. For example, you could create subdirectories /p200/videos, /p200/databases, /p200/games, etc. If you roll back /p200 you would rollback all subdirectories. If you create multiple datasets, you can snapshot, export, and import each independently. This is also the reason why the root directory of the pool is usually empty except the mountpoints of the child-datasets.

 

[Lamia]

If you were to create only subdirectories in this directory, you would be missing one of the best features of ZFS, snapshots.

I reckon he is yet to explore snapshots I'm detail..ZFS can be confusing to a new user. You want to set snapdir=true to see the snapshots. You can compress, limit size and many more.Keep it up fff2024g.

 

[Mirror176]

DEar all:
maybe i known my question . we can create folder in zfs pool anywhere. the folder was belongs dataset . dataset can include more folder , but folder don't include dataset . we can mount other disk space to the folder , we can't mount other disk space to the dataset ... is that right ?

Datasets hold files and folders. Folders do not hold datasets. Datasets, unlike other filesystem mountpoints, do not require you create a folder to mount a filesystem to that point. Directories are created and destroyed as needed for ZFS mounting to work.

It does get a little confusing sometimes since you can talk to datasets with zfs commands by referring to the dataset name or to the mountpoint of the dataset.