---
title: Use Ceph Block Device
url: https://devopstales.github.io/linux/ceph-block-device/
date: 2019-03-12
keywords: rook, ceph, Block Device
---


Ceph block devices are thin-provisioned, resizable and store data striped over multiple OSDs in a Ceph cluster. Ceph block devices leverage RADOS capabilities such as snapshotting, replication and consistency. Ceph’s RADOS Block Devices (RBD) interact with OSDs using kernel modules or the librbd library.

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### Environment
```
192.168.1.31    ceph01
192.168.1.32    ceph02
192.168.1.33    ceph03
```

### Install Client cli
```
ceph-deploy install client
ceph-deploy admin client

sudo chmod 644 /etc/ceph/ceph.client.admin.keyring
```

### Basic Usage
```
# create pool
ceph osd pool create stack 64 64

# createdisk to pool
rbd create disk01 --size 10G --image-feature layering --pool stack --allow-shrink

# show list
rbd ls -l

# show info
rbd --image disk01 -p stack info

# resize
rbd resize --image disk01 -p stack --size 6G

# remove
rbd rm disk01 -p stack

# map the image to device
sudo rbd map disk01

# show mapping
rbd showmapped

# format with XFS
sudo mkfs.xfs /dev/rbd0

# mount device
sudo mount /dev/rbd0 /mnt
df -hT
```