Chapter 3. Client Quick Start

Create a user for your block device. This step requires the Ceph CLI interface with administrative privileges. To create a user, execute ceph auth get-or-create and output the result to a keyring file.

# ceph auth get-or-create USERTYPE.USERID {daemon} \
 'allow <r|w|x|*|...> [pool={pool-name}]' \
 -o /etc/ceph/rbd.keyring

A block device user should have rwx permissions on OSDs, because block devices use classes and therefore require execute x permissions. The following example limits the client.rbd user to the default rbd pool. For example, on the ceph-client node, execute:

# ceph auth get-or-create client.rbd \
mon 'allow r' osd 'allow rwx pool=rbd' \
-o /etc/ceph/rbd.keyring

See the Red Hat Ceph Storage Administration Guide for additional details on user management.

On the ceph-client node, create a block device image.

# rbd create foo --size 4096 --pool rbd \
--name client.rbd --keyring /etc/ceph/rbd.keyring

On the ceph-client node, map the image to a block device.

# rbd map foo --pool rbd \
--name client.rbd --keyring /etc/ceph/rbd.keyring

Use the block device by creating a file system on the ceph-client node.

# mkfs.ext4 -m0 /dev/rbd/rbd/foo

This may take a few moments.

Mount the file system on the ceph-client node.

# mkdir /mnt/ceph-block-device
# mount /dev/rbd/rbd/foo /mnt/ceph-block-device
cd /mnt/ceph-block-device

Enable the rhel-7-server-rhceph-1.3-tools-rpms repository on the client-node node, if you haven’t done so already.

# subscription-manager repos --enable=rhel-7-server-rhceph-1.3-tools-rpms

From the working directory of your administration server, install the Ceph Object Gateway package on the client-node node. For example:

ceph-deploy install --rgw <client-node> [<client-node> ...]

From the working directory of your administration server, create an instance of the Ceph Object Gateway on the client-node. For example:

ceph-deploy rgw create <client-node>

Once the gateway is running, you should be able to access it on port 7480. (for example, http://client-node:7480).

To change the default port (for example, to port 80), modify your Ceph configuration file. Add a section entitled [client.rgw.<client-node>], replacing <client-node> with the short node name of your Ceph client node ($ hostname -s). For example, if your node name is client-node, add a section like this after the [global] section:

[client.rgw.client-node]
rgw_frontends = "civetweb port=80"

To make the new port setting take effect, restart the Ceph Object Gateway.

# systemctl restart ceph-radosgw.service

Finally, check to ensure that the port you selected is open on the node’s firewall (for example, port 80). If it is not open, add the port and reload the firewall configuration. For example:

# firewall-cmd --list-all
# firewall-cmd --zone=public --add-port 80/tcp
# firewall-cmd --zone=public --add-port 80/tcp --permanent