# [manual] create erasure-coding ceph filesystem pool

Cheatsheet how to setup a erasure coding pool, add it to a ceph filesystem and configure files/directories to use the ec pool.

```console
root@ceph:~$ ceph osd erasure-code-profile set ec-62-profile k=6 m=2 crush-failure-domain=osd crush-device-class=hdd
root@ceph:~$ ceph osd pool create glacier_data_ec-62 erasure ec-62-profile
root@ceph:~$ ceph osd pool set glacier_data_ec-62 allow_ec_overwrites true
root@ceph:~$ ceph osd pool application enable glacier_data_ec-62 cephfs
root@ceph:~$ ceph fs add_data_pool glacier glacier_data_ec-62
```

## Managing ceph dir/file layouts

### Files
```console
root@ceph:~$ touch file
root@ceph:~$ getfattr -n ceph.file.layout file
# file: file
ceph.file.layout="stripe_unit=4194304 stripe_count=1 object_size=4194304 pool=glacier_data"
root@ceph:~$ setfattr -n ceph.file.layout.pool -v glacier_data_ec-62 file 
root@ceph:~$ getfattr -n ceph.file.layout file
# file: file
ceph.file.layout="stripe_unit=4194304 stripe_count=1 object_size=4194304 pool=glacier_data_ec-62"
```

### Directories
```console
root@ceph:~$ mkdir directory
root@ceph:~$ getfattr -n ceph.dir.layout directory
directory: ceph.dir.layout: No such attribute
root@ceph:~$ setfattr -n ceph.dir.layout.pool -v glacier_data_ec-62 directory
root@ceph:~$ getfattr -n ceph.dir.layout directory
# file: directory
ceph.dir.layout="stripe_unit=4194304 stripe_count=1 object_size=4194304 pool=glacier_data_ec-62"
```

## Sources

- [Ceph Blog](https://ceph.io/en/news/blog/2017/new-luminous-erasure-coding-rbd-cephfs/)
- [Ceph Erasure Coding Documentation](https://docs.ceph.com/en/latest/rados/operations/erasure-code/)
- [Ceph Filesystem Documentation](https://docs.ceph.com/en/latest/cephfs/createfs/)
- [Ceph File Layout Documentation](https://docs.ceph.com/en/latest/cephfs/file-layouts/)
- [SUSE Documentation](https://documentation.suse.com/de-de/ses/6/html/ses-all/cha-ceph-as-cephfs.html)
- [Proxmox Documentation](https://pve.proxmox.com/wiki/Storage:_CephFS)
- [storage-base.de](https://storage-base.de/knowledgebase/107/Erasure-Coding-Pool-erstellen.html)
- [spinics.net](https://www.spinics.net/lists/ceph-users/msg44595.html)