CL260 - ch06s02

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Guided Exercise: Managing RADOS Block Devices

In this exercise, you will create and configure RADOS block devices.

Outcomes

You should be able to create and manage RADOS block device images and use them as regular block devices.

As the student user on the workstation machine, use the lab command to prepare your system for this exercise.

This command confirms that the hosts required for this exercise are accessible.

[student@workstation ~]$ lab start block-devices

Procedure 6.1. Instructions

Verify that the Red Hat Ceph cluster is in a healthy state.
1. Log in to clienta as the admin user and use sudo to run the cephadm shell.
```
[student@workstation ~]$ ssh admin@clienta
[admin@clienta ~]$ sudo cephadm shell
[ceph: root@clienta /]#
```
2. Verify that the cluster status is HEALTH_OK.
```
[ceph: root@clienta /]# ceph health
HEALTH_OK
```

Create a replicated pool called test_pool with 32 placement groups. Set the application type for the pool to rbd.

Create the pool test_pool.

[ceph: root@clienta /]# ceph osd pool create test_pool 32 32
pool 'test_pool' created

Set rbd as the application type for the pool.

[ceph: root@clienta /]# rbd pool init test_pool

List the configured pools and view the usage and availability for test_pool. The ID of test_pool might be different in your lab environment.

[ceph: root@clienta /]# ceph df
--- RAW STORAGE ---
CLASS     SIZE    AVAIL     USED  RAW USED  %RAW USED
hdd     90 GiB   90 GiB  136 MiB   136 MiB       0.15
TOTAL   90 GiB   90 GiB  136 MiB   136 MiB       0.15

--- POOLS ---
POOL                   ID  PGS   STORED  OBJECTS     USED  %USED  MAX AVAIL
...output omitted...
test_pool               6   32      9 B        1    8 KiB      0     28 GiB

Create a dedicated Ceph user called client.test_pool.clientb. Configure the clienta node with the user's key-ring file to access the RBD pool containing the RBD images.

Create the client.test_pool.clientb user and display the new file.

[ceph: root@clienta /]# ceph auth get-or-create client.test_pool.clientb \
 mon 'profile rbd' osd 'profile rbd' \
 -o /etc/ceph/ceph.client.test_pool.clientb.keyring

[ceph: root@clienta /]# cat /etc/ceph/ceph.client.test_pool.clientb.keyring
[client.test_pool.clientb]
	key = AQAxBE1h79iUNhAAnBWswmX1Wk1Dhlq4a3U61Q==

Verify that the client.test_pool.clientb user now exists.

[ceph: root@clienta /]# ceph auth get client.test_pool.clientb
[client.test_pool.clientb]
	key = AQAxBE1h79iUNhAAnBWswmX1Wk1Dhlq4a3U61Q==
	caps mon = "profile rbd"
	caps osd = "profile rbd"
exported keyring for client.test_pool.clientb

Open a second terminal window and log in to the clientb node as the admin user. Copy the key-ring file for the new test_pool user. Use the client.test_pool.clientb user name when connecting to the cluster.
1. Log in to clientb as the admin user and switch to the root user.
```
[student@workstation ~]$ ssh admin@clientb
[admin@clientb ~]$ sudo -i
[root@clientb ~]#
```
2. Install the ceph-common package on the clientb node.
```
[root@clientb ~]# yum install -y ceph-common
...output omitted...
Complete!
```
3. Go to the first terminal and copy the Ceph configuration and the key-ring files from the /etc/ceph/ directory on the clienta node to the /etc/ceph/ directory on the clientb node.
```
[ceph: root@clienta /]# scp \
/etc/ceph/{ceph.conf,ceph.client.test_pool.clientb.keyring} \
root@clientb:/etc/ceph
root@clientb's password: redhat
...output omitted...
```
4. Go to the second terminal window. Temporarily set the default user ID used for connections to the cluster to test_pool.clientb.
```
[root@clientb ~]# export CEPH_ARGS='--id=test_pool.clientb'
```
5. Verify that you can connect to the cluster.
```
[root@clientb ~]# rbd ls test_pool
```

Create a new RADOS Block Device Image and map it to the clientb machine.

Create an RBD image called test in the test_pool pool. Specify a size of 128 megabytes.

[root@clientb ~]# rbd create test_pool/test --size=128M

[root@clientb ~]# rbd ls test_pool
test

Verify the parameters of the RBD image.

[root@clientb ~]# rbd info test_pool/test
rbd image 'test':
	size 128 MiB in 32 objects
	order 22 (4 MiB objects)
	snapshot_count: 0
	id: 867cba5c2d68
	block_name_prefix: rbd_data.867cba5c2d68
	format: 2
	features: layering, exclusive-lock, object-map, fast-diff, deep-flatten
	op_features:
	flags:
	create_timestamp: Thu Sep 23 18:54:35 2021
	access_timestamp: Thu Sep 23 18:54:35 2021
	modify_timestamp: Thu Sep 23 18:54:35 2021

Map the RBD image on the clientb node by using the kernel RBD client.

[root@clientb ~]# rbd map test_pool/test
/dev/rbd0

[root@clientb ~]# rbd showmapped
id  pool       namespace  image  snap  device
0   test_pool             test   -     /dev/rbd0

Verify that you can use the RBD image mapped on the clientb node like a regular disk block device.

Format the device with an XFS file system.

[root@clientb ~]# mkfs.xfs /dev/rbd0
meta-data=/dev/rbd0              isize=512    agcount=8, agsize=4096 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1
data     =                       bsize=4096   blocks=32768, imaxpct=25
         =                       sunit=16     swidth=16 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=1872, version=2
         =                       sectsz=512   sunit=16 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
Discarding blocks...Done.

Create a mount point for the file system.
```
[root@clientb ~]# mkdir /mnt/rbd
```
Mount the file system created on the /dev/rbd0 device.
```
[root@clientb ~]# mount /dev/rbd0 /mnt/rbd
```

Change the ownership of the mount point.

[root@clientb ~]# chown admin:admin /mnt/rbd

Review the file-system usage.

[root@clientb ~]# df /mnt/rbd
Filesystem     1K-blocks  Used Available Use% Mounted on
/dev/rbd0         123584  7940    115644   7% /mnt/rbd

Add some content to the file system.

[root@clientb ~]# dd if=/dev/zero of=/mnt/rbd/test1 bs=10M count=1
1+0 records in
1+0 records out
10485760 bytes (10 MB, 10 MiB) copied, 0.00838799 s, 1.3 GB/s

[root@clientb ~]# ls /mnt/rbd
test1

Review the file-system usage.

[root@clientb ~]# df /mnt/rbd
Filesystem     1K-blocks  Used Available Use% Mounted on
/dev/rbd0         123584 18180    105404  15% /mnt/rbd

Review the content of the cluster.

[root@clientb ~]# ceph df
--- RAW STORAGE ---
CLASS     SIZE    AVAIL     USED  RAW USED  %RAW USED
hdd     90 GiB   90 GiB  158 MiB   158 MiB       0.17
TOTAL   90 GiB   90 GiB  158 MiB   158 MiB       0.17

--- POOLS ---
POOL                   ID  PGS   STORED  OBJECTS     USED  %USED  MAX AVAIL
...output omitted...
test_pool               6   32  2.5 MiB       14  7.5 MiB      0     28 GiB

Unmount the file system and unmap the RBD image on the clientb node.

[root@clientb ~]# umount /mnt/rbd
[root@clientb ~]# rbd unmap /dev/rbd0
[root@clientb ~]# rbd showmapped

Configure the client system so that it persistently mounts the test_pool/test RBD image as /mnt/rbd.

Create a single-line entry for test_pool/test in the /etc/ceph/rbdmap RBD map file. The RBD mount daemon should authenticate as the test_pool.clientb user using the appropriate key-ring file. The resulting file should have the following contents:

[root@clientb ~]# cat /etc/ceph/rbdmap
# RbdDevice             Parameters
#poolname/imagename     id=client,keyring=/etc/ceph/ceph.client.keyring
test_pool/test          id=test_pool.clientb,keyring=/etc/ceph/ceph.client.test_pool.clientb.keyring

Create an entry for /dev/rbd/test_pool/test in the /etc/fstab file. The resulting file should have the following contents:

[root@clientb ~]# cat /etc/fstab
UUID=fe1e8b67-e41b-44b8-bcfe-e0ec966784ac /                       xfs     defaults        0 0
UUID=F537-0F4F          /boot/efi               vfat    defaults,uid=0,gid=0,umask=077,shortname=winnt 0 2
/dev/rbd/test_pool/test /mnt/rbd                xfs noauto 0 0

Verify your RBD map configuration. Use the rbdmap command to map and unmap configured RBD devices.

[root@clientb ~]# rbdmap map
[root@clientb ~]# rbd showmapped
id  pool       namespace  image  snap  device
0   test_pool             test   -     /dev/rbd0
[root@clientb ~]# rbdmap unmap
[root@clientb ~]# rbd showmapped

After you have verified that the RBD mapped devices work, enable the rbdmap service. Reboot the clientb node to verify that the RBD device mounts persistently.

[root@clientb ~]# systemctl enable rbdmap
Created symlink /etc/systemd/system/multi-user.target.wants/rbdmap.service → /usr/lib/systemd/system/rbdmap.service.

[root@clientb ~]# reboot
Connection to clientb closed by remote host.
Connection to clientb closed.

When the clientb node finishes rebooting, log in and verify that it has mounted the RBD device.

[student@workstation ~]$ ssh admin@clientb
[admin@clientb ~]$ df /mnt/rbd
Filesystem     1K-blocks  Used Available Use% Mounted on
/dev/rbd0         123584 18180    105404  15% /mnt/rbd

Unmount your file system, unmap and delete the test_pool/test RBD image, and delete the temporary objects to clean up your environment.

Unmount the /mnt/rbd file system and unmap the RBD image.

[admin@clientb ~]$ sudo -i
[root@clientb ~]# rbdmap unmap
[root@clientb ~]# df | grep rbd
[root@clientb ~]# rbd showmapped

Remove the RBD entry from the /etc/fstab file. The resulting file should contain the following:

[root@clientb ~]# cat /etc/fstab
UUID=fe1e8b67-e41b-44b8-bcfe-e0ec966784ac /                       xfs     defaults        0 0
UUID=F537-0F4F          /boot/efi               vfat    defaults,uid=0,gid=0,umask=077,shortname=winnt 0 2

Remove the RBD map entry for test_pool/test from the /etc/ceph/rbdmap file. The resulting file should contain the following:

[root@clientb ~]# cat /etc/ceph/rbdmap
# RbdDevice             Parameters
#poolname/imagename     id=client,keyring=/etc/ceph/ceph.client.keyring

Delete the test RBD image.

[root@clientb ~]# rbd rm test_pool/test --id test_pool.clientb
Removing image: 100% complete...done.

Verify that the test_pool RBD pool does not yet contain extra data. The test_pool pool should initially contain the three list objects.
```
[root@clientb ~]# rados -p test_pool ls --id test_pool.clientb
rbd_directory
rbd_info
rbd_trash
```

Exit and close the second terminal. In the first terminal, return to workstation as the student user.

[root@clientb ~]# exit
[admin@clientb ~]$ exit
[student@workstation ~]$ exit

[ceph: root@clienta /]# exit
exit
[root@clienta ~]# exit
[admin@clienta ~]$ exit
[student@workstation ~]$

Finish

On the workstation machine, use the lab command to complete this exercise. This is important to ensure that resources from previous exercises do not impact upcoming exercises.

[student@workstation ~]$ lab finish block-devices

This concludes the guided exercise.

Discuss Cloud Storage with Red Hat Ceph Storage

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Red Hat Ceph Storage for OpenStack (CL260)

Haley_Ruccio

3 sie 2023

Build, expand and maintain cloud-scale, clustered storage for your applications with Red Hat Ceph StorageCloud Storage with Red Hat Ceph Storage (CL260) is designed for storage administrators and cloud operators who deploy Red Hat Ceph Storage in a production data center environment or as a component of a Red Hat OpenStack Platform or OpenShift Container Platform infrastructure. Learn how to deploy, manage, and scale a Ceph storage cluster to provide hybrid storage resources, including Amazon S3 and OpenStack Swift-compatible object storage, Ceph-native and iSCSI-based block storage, and shared file storage. This course is based on Red Hat Ceph Storage 5.0.Course summaryDeploy and manage a Red Hat Ceph Storage cluster on commodity servers.Perform common management operations using the web-based management interface.Create, expand, and control access to storage pools provided by the Ceph cluster.Access Red Hat Ceph Storage from clients using object, block, and file-based methods.Analyze and tune Red Hat Ceph Storage performance.Integrate Red Hat OpenStack Platform image, object, block, and file storage with a Red Hat Ceph Storage cluster.Integrate OpenShift Container Platform with a Red Hat Ceph Storage cluster.Target AudienceThis course is intended for storage administrators and cloud operators who want to learn how to deploy and manage Red Hat Ceph Storage on servers in an enterprise data center or within a Red Hat OpenStack Platform or OpenShift Container Platform environment.Developers writing applications that use cloud-based storage will learn the distinctions of various storage types and client access methods.Recommended trainingTake our free assessment to gauge whether this offering is the best fit for your skills.Red Hat Certified System Administrator (RHCSA) certification, or equivalent experience.For candidates that have not earned an RHCSA or equivalent, confirmation of the correct skill set knowledge can be obtained by taking the online skills assessment.Some experience with storage administration is recommended but not required.Technology considerationsThis course does not have any special technical requirements.This course is not intended for BYOD.Internet access is recommended.

Welcome to the Red Hat Ceph Storage for OpenStack (CL260) group in the Red Hat Learning Community!

cschunke

31 lip 2023

We are excited to launch a space dedicated to the Red Hat Training course CL260! To gain the most value from this group - click the "Join Group" button in the upper right hand corner of the group home page.We encourage group members to collaborate in this group to discuss topics, ask questions, share best practices and tips, provide course feedback, and share their accomplishments as it relates to CL260.Read more about Red Hat Ceph Storage for OpenStack here.

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Revision: cl260-5.0-29d2128