CL260 - ch10s04

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Guided Exercise: Managing Shared File Storage

In this exercise, you configure shared file client access with CephFS.

Outcomes

You should be able to manage CephFS and create snapshots.

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

[student@workstation ~]$ lab start fileshare-manage

Procedure 10.2. Instructions

The serverc, serverd, and servere nodes are an operational 3-node Ceph cluster. All three nodes operate as a MON, a MGR, and an OSD host with at least one colocated OSD.
The clienta node is set up as your admin node server and you use it to install the Metadata Server (MDS) on serverc.
The mycephfs CephFS file system is mounted on the /mnt/mycephfs folder with the key ring for the admin user.

[student@workstation ~]$ ssh admin@clienta
[admin@clienta ~]$

Create a /mnt/mycephfs/dir1 directory. Create an empty file /mnt/mycephfs/dir1/ddtest. Modify the ceph.dir.layout.stripe_count layout attribute for the /mnt/mycephfs/dir1 directory. Verify that the attribute change does not affect existing files within the directory, but that any newly created files inherit it. The attr package is preinstalled for you.
1. Use the getfattr command to create and verify the layout of the /mnt/cephfs/dir1 directory. This command should not return any layout attribute that is associated with this directory.
```
[admin@clienta ~]$ mkdir /mnt/mycephfs/dir1
[admin@clienta ~]$ touch /mnt/mycephfs/dir1/ddtest
[admin@clienta ~]$ getfattr -n ceph.dir.layout /mnt/mycephfs/dir1
/mnt/mycephfs/dir1: ceph.dir.layout: No such attribute
```
  Note
  If a directory has no layout attributes, then it inherits the layout of its parent. You must set the layout attributes of a directory before you can view them. By default, layout attributes are set on only the top-level directory of the mounted CephFS file system (on the mount point).
2. Use the setfattr command to change the layout of the /mnt/mycephfs/dir1 directory.
```
[admin@clienta ~]$ setfattr -n ceph.dir.layout.stripe_count \
-v 2 /mnt/mycephfs/dir1
```
3. Verify the layout of the /mnt/mycephfs/dir1 directory again. Layout attributes should now be available for this directory. Settings other than the one that you specified are inherited from the closest parent directory where attributes were set.
```
[admin@clienta ~]$ getfattr -n ceph.dir.layout /mnt/mycephfs/dir1
getfattr: Removing leading '/' from absolute path names
# file: mnt/mycephfs/dir1
ceph.dir.layout="stripe_unit=4194304 stripe_count=2 object_size=4194304 pool=mycephfs_data"
```
4. Verify the layout for the /mnt/mycephfs/dir1/ddtest file and notice that the layout does not change for this file, which existed before the layout change.
```
[admin@clienta ~]$ getfattr -n ceph.file.layout /mnt/mycephfs/dir1/ddtest
getfattr: Removing leading '/' from absolute path names
# file: mnt/mycephfs/dir1/ddtest
ceph.file.layout="stripe_unit=4194304 stripe_count=1 object_size=4194304 pool=mycephfs_data"
```
5. Create a file called anewfile under the /mnt/cephfs/dir1/ directory. Notice how the stripe_count for the layout of this file matches the new layout of the /mnt/cephfs/dir1/ directory. The new file inherits the layout attributes from its parent directory at creation time.
```
[admin@clienta ~]$ touch /mnt/mycephfs/dir1/anewfile
[admin@clienta ~]$ getfattr -n ceph.file.layout /mnt/mycephfs/dir1/anewfile
getfattr: Removing leading '/' from absolute path names
# file: mnt/mycephfs/dir1/anewfile
ceph.file.layout="stripe_unit=4194304 stripe_count=2 object_size=4194304 pool=mycephfs_data"
```
6. Modify the layout of the /mnt/mycephfs/dir1/anewfile file so that the stripe_count value is 3. You can modify a specific file layout if the file is empty. Ensure that the new value for stripe_count is correct.
```
[admin@clienta ~]$ setfattr -n ceph.file.layout.stripe_count \
-v 3 /mnt/mycephfs/dir1/anewfile
[admin@clienta ~]$ getfattr -n ceph.file.layout /mnt/mycephfs/dir1/anewfile
getfattr: Removing leading '/' from absolute path names
# file: mnt/mycephfs/dir1/anewfile
ceph.file.layout="stripe_unit=4194304 stripe_count=3 object_size=4194304 pool=mycephfs_data"
```
7. Ensure that the /mnt/mycephfs/dir1/anewfile file is not empty. Verify that you cannot modify a specific file's layout attributes if the file is not empty.
```
[admin@clienta ~]$ echo "Not empty" > /mnt/mycephfs/dir1/anewfile
[admin@clienta ~]$ setfattr -n ceph.file.layout.stripe_count \
-v 4 /mnt/mycephfs/dir1/anewfile
setfattr: /mnt/mycephfs/dir1/anewfile: Directory not empty
```
8. Clear the configured layout attributes for the /mnt/mycephfs/dir1 directory. Verify the new layout settings (that are inherited from the top of the CephFS file system) by creating a file called a3rdfile.
```
[admin@clienta ~]$ setfattr -x ceph.dir.layout /mnt/mycephfs/dir1
[admin@clienta ~]$ touch /mnt/mycephfs/dir1/a3rdfile
[admin@clienta ~]$ getfattr -n ceph.file.layout /mnt/mycephfs/dir1/a3rdfile
getfattr: Removing leading '/' from absolute path names
# file: mnt/mycephfs/dir1/a3rdfile
ceph.file.layout="stripe_unit=4194304 stripe_count=1 object_size=4194304 pool=mycephfs_data"
```

Create a snapshot for your CephFS file system. Mount the CephFS file system on /mnt/mycephfs as the user restricteduser.

Unmount the /mnt/mycephfs folder and mount again the CephFS file system to that folder as the user restricteduser.

[admin@clienta ~]$ sudo umount /mnt/mycephfs
[admin@clienta ~]$ sudo mount.ceph serverc.lab.example.com:/ \
/mnt/mycephfs -o name=restricteduser

Navigate to the hidden .snap folder in /mnt/mycephfs.
```
[admin@clienta ~]$ cd /mnt/mycephfs/.snap
```

Create a mysnapshot folder, which is the snapshot name. As the user restricteduser does not currently have snapshot permissions, you must grant snapshot permissions to this user. After you set the permissions, you must remount the CephFS file system to use the new permissions.

[admin@clienta .snap]$ mkdir mysnapshot
mkdir: cannot create directory 'mysnapshot': Permission denied
[admin@clienta .snap]$ sudo cephadm shell
[ceph: root@clienta /]# ceph auth get client.restricteduser
[client.restricteduser]
	key = AQBc315hI7PaBRAA9/9fdmj+wjblK+izstA0aQ==
	caps mds = "allow r fsname=mycephfs, allow rw fsname=mycephfs path=/dir2"
	caps mon = "allow r fsname=mycephfs"
	caps osd = "allow rw tag cephfs data=mycephfs"
exported keyring for client.restricteduser
[ceph: root@clienta /]# ceph auth caps client.restricteduser \
mds 'allow rws fsname=mycephfs' \
mon 'allow r fsname=mycephfs' \
osd 'allow rw tag cephfs data=mycephfs'
updated caps for client.restricteduser
[ceph: root@clienta /]# exit
exit
[admin@clienta .snap]$ cd
[admin@clienta ~]$ sudo umount /mnt/mycephfs
[admin@clienta ~]$ sudo mount.ceph serverc.lab.example.com:/ \
/mnt/mycephfs -o name=restricteduser
[admin@clienta ~]$ cd /mnt/mycephfs/.snap
[admin@clienta .snap]$ mkdir mysnapshot

Check that the files in the snapshot are the same as the files in the mounted CephFS file system.

[admin@clienta .snap]$ tree /mnt/mycephfs
/mnt/mycephfs
└── dir1
    ├── a3rdfile
    ├── anewfile
    └── ddtest

1 directory, 3 files
[admin@clienta .snap]$ tree /mnt/mycephfs/.snap/mysnapshot
/mnt/mycephfs/.snap/mysnapshot
└── dir1
    ├── a3rdfile
    ├── anewfile
    └── ddtest

1 directory, 3 files

Schedule to create an hourly snapshot of your CephFS file system's root folder.

Use sudo to run the cephadm shell. Enable the snapshot module.

[admin@clienta .snap]$ sudo cephadm shell
[ceph: root@clienta /]# ceph mgr module enable snap_schedule

Schedule to create the snapshot every hour.

[ceph: root@clienta /]# ceph fs snap-schedule add / 1h
Schedule set for path /

Check that your snapshot schedule is correctly created and in an active state.

[ceph: root@clienta /]# ceph fs snap-schedule status /
{"fs": "mycephfs", "subvol": null, "path": "/", "rel_path": "/", "schedule": "1h", "retention": {}, "start": "2021-10-06T00:00:00", "created": "2021-10-06T08:59:16", "first": "2021-10-06T09:00:00", "last": "2021-10-06T09:00:00", "last_pruned": null, "created_count": 1, "pruned_count": 0, "active": true}

Exit from the cephadm shell. Check that your snapshot is correctly created in your .snap folder.

[ceph: root@clienta /]# exit
exit
[admin@clienta .snap]$ ls
mysnapshot  scheduled-2021-10-06-09_00_00
[admin@clienta .snap]$ tree
.
├── mysnapshot
│   └── dir1
│       ├── a3rdfile
│       ├── anewfile
│       └── ddtest
└── scheduled-2021-10-06-09_00_00
    └── dir1
        ├── a3rdfile
        ├── anewfile
        └── ddtest

4 directories, 6 files

Creating the scheduled snapshot might take time. As you scheduled it every hour, it might take up to one hour to be triggered. You do not have to wait until the snapshot is created.

Return to workstation as the student user.
```
[admin@clienta .snap]$ exit
[student@workstation ~]$
```
Warning
Run the lab finish script on the workstation server so that the clienta node can be safely rebooted without mount conflicts.

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 fileshare-manage

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

Cloud Storage with Red Hat Ceph Storage

Guided Exercise: Managing Shared File Storage

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