Object Store¶
Introduction¶
Chameleon provides an object store service through the OpenStack Swift interface. It is intended to be used for storing and retrieving data used during experiments, such as input files needed for your applications, or results produced by your experiments.
Hint
Chameleon object store service is currently backed by a Ceph cluster with more than 1.6 PB of capacity. The data is replicated, keeping two copies of each object, effectively providing over 800 TB of storage available to users. This storage capacity will increase as the project goes on. The replication should provide good availability in case of hardware failures. However, all copies are kept within the same data center and are not backed up on a separate system; if you feel that this does not provide sufficient reliability in your case, you should consider backing up really critical data externally.
Availability¶
You can access the Object Store from instances running on CHI@TACC, CHI@UC and KVM@TACC by using your CHI@TACC OpenStack RC file (UC users will see more latency impact since the Object Store is located at TACC). To make it easier for you to use the Object Store client, we installed it in all appliances supported by Chameleon. Additionally, you can also access the Object Store from the CHI@TACC web interface under the Object Store panel.
Objects and Containers¶
Objects are equivalent to individual files. They are stored in Containers, which are data structures that can contain multiple Objects. When uploading Objects, they must be stored inside of Containers. You may perform operations on individual Objects inside Containers, such as downloading or deleting them. You may also work with entire Containers and perform operations such as downloading an entire Container.
Managing Object Store using the GUI¶
Note
The Object Store is implemented at TACC. Therefore, only CHI@TACC implements a GUI interface for the Object Store. However, the CLI works for both CHI@TACC and CHI@UC.
To access the Object Store using the GUI at CHI@TACC, use the navigation sidebar to go to Project > Object Store > Containers.
The Containers page
Working with Containers¶
To create a container, click the +Container button. This will open the Create Container dialog.
The Create Container dialog
Choose a unique name of your container and set the visibility to either Public or Not Public. When you are finished, click the Submit button. You will see your new Container appear in the list on the Containers page.
The Container list
You may click on a Container to see the details and work with Objects belong to it.
Container details
Attention
Downloading a container is not available from the GUI. Use the CLI to download containers.
You may delete a container by clicking the Delete icon in the upper right of the Container Detail Panel.
The Delete Container button
Working with Objects¶
To upload a local file to a container, click the button with the Upload symbol next to the search bar.
The Upload button
This will open the Upload File dialog.
The Upload File dialog
Choose a file to upload from your local file system and give a name to the object.
Working with Folders¶
If you wish to create a Folder within your Container, click the +Folder button and give a name to your folder in the Create Folder dialog.
The Create Folder dialog
Your new folder will appear in the Container details.
A Container with a Folder
You may browse your folder and upload files to it by clicking on the folder.
A Folder within the Container
Managing Object Store using the CLI¶
Tip
Reading The Command Line Interface is highly recommanded before continuing on the following sections.
In addition to Installing the CLI, you must also install python-swiftclient package:
pip install python-swiftclient
Then, you must set environment variables for your account and project using The OpenStack RC Script.
Working with Containers¶
To create a Container, use the following command:
openstack container create <container_name>
Tip
By default, the Container created using the above command will not be visible to the public.
To view all containers that belong to your project, run:
openstack container list
Tip
You may use --prefix <prefix> as a filter to list the containers whose name starts with <prefix>.
To see details of a container, use the command:
openstack container show <container_name>
To view a list of objects within a container, use the command:
openstack object list <container_name>
To download a container with all the objects belong to it, use the following command:
openstack container save <container_name>
To delete a container and wipe out all the objects belong to it, use the following command:
openstack container delete <container_name>
Working with Objects¶
You may upload a file from your local machine to a container using the following command:
openstack object create <container_name> <local_filename>
Tip
Optionally, you may name the object differently from it’s original name in your local machine by using the --name <object_name> parameter.
To delete an object from a container, run:
openstack object delete <container_name> <object_name>
If you wish to download an individual object directly from a container, use the command:
openstack object save <container_name> <object_name>
Working with Folders¶
There isn’t “folders” when you managing the Object Store with the CLI. However, when you create an object, you may use the delimiter / to specify the path.
Mounting Object Store as a File System¶
When logged into an instance using Chameleon supported images, such as CC-CentOS7 and CC-Ubuntu16.04, you may use the pre-installed cloudfuse (Source: Github) to mount your Chameleon Object Store as a directory on your Linux environment.
Before mount, create a ~/.cloudfuse file with the following content:
username=<username>
password=<password>
tenant=<projectname>
authurl=https://chi.tacc.chameleoncloud.org:5000/v2.0
Replace username and password with your Chameleon username and password, and replace projectname with your Chameleon project name.
Then mount with the following command:
cloudfuse <mount_dir>
Or you can specify your username and password as mount options:
cloudfuse -o username=<username>,password=<password> <mount_dir>
Now you can access your Chameleon Object Store as your local file system.
To unmount:
fusermount -u <mount_dir>