Data transfer with object storage

Use EGI Data transfer to handle data in object storage

Overview

This tutorial describes the EGI Data Transfer using FTS transfers services and WebFTS. In the following paragraps you will learn how to:

  • use the FTS command-line client
  • use the WebFTS web interface

to perform data transfers between a Grid storage and object storage or between two object storage.

Prerequisites

As first step please make sure that you have installed the FTS client as described in Data Transfer, and in particular Clients for the command-line FTS and to have your certificate installed in your browser to use WebFTS browser based client.

To access services and resources in the EGI Federated Cloud, you will need:

  • An EGI Check-in account, you can sign up here
  • Enrollment into a Virtual Organisation (VO) that has access to the services and resources you need
  • An Object Storage for which you need to have all the credentials available (any S3 compatible storage should work)
  • Permission to add the Object Storage credential to the FTS server or alternatively for this operation you may contact support support at egi.eu.

FTS client usage

Step 1 Configuration check and Proxy creation

For this two steps please refer to the “Data transfer with grid storage” tutorial.

Step 2 Find the storage

As for the “Data transfer with grid storage” tutorial you can look for the available storage on VAPOR service while the Object Store can be one created as described in the Object Storage section or trough a provider such as Amazon, Azure, etc

Step 3 Add the Object Storage credential to the FTS server

Following is an example of the command that can be used to add the Object Store credential to the FTS server. The fist step is to register the Object Storage. The name of the storage, is S3: + the domain part of the URL (for example https://s3.cl2.du.cesnet.cz -> S3:s3.cl2.du.cesnet.cz)

$ curl -E "${X509_USER_PROXY}" \
  --cacert "${X509_USER_PROXY}" \
  --capath "/etc/grid-security/certificates" \
  https://fts3devel01.cern.ch:8446/config/cloud_storage \
  -H "Content-Type: application/json" \
  -X POST \
  -d '{"storage_name":"S3:s3.cl2.du.cesnet.cz"}'

And then, add the keys, so the requests can be signed.

$ curl -E "${X509_USER_PROXY}" \
  --cacert "${X509_USER_PROXY}" \
  --capath "/etc/grid-security/certificates" \
  "https://fts3devel01.cern.ch:8446/config/cloud_storage/S3:s3.cl2.du.cesnet.cz" \
  -H "Content-Type: application/json" \
  -X POST \
  --data @config.json

Where config.json is a JSON file with the following content:

{
  "vo_name": "/dteam/Role=NULL/Capability=NULL",
  "access_key": "ACCESS_KEY",
  "secret_key": "SECRET_KEY"
}

Where ACCESS_KEY and SECRET KEY are the corresponding key necessary to access the object storage. See also the S3 Support pages on the FTS docs pages.

Step 4 Transfer between a grid storage and an object storage

For the grid storage to use please follow the details described in the section “Find the storage” of the “Data transfer with grid storage” tutorial. In the following examples, an object storage available in s3://s3.cl2.du.cesnet.cz/ with an already available bucket is used. To manage the object storage is possible to use any compatible tool. Following will be only shown an example of transfer.

$ fts-transfer-submit --s3alternate \
  -s https://fts3-public.cern.ch:8446 \
  https://dc2-grid-64.brunel.ac.uk/dpm/brunel.ac.uk/home/dteam/1M \
  s3://s3.cl2.du.cesnet.cz/bucket-name/1M.3
247b7ca2-4c4d-11ec-84d0-fa163e5dcbe0

The command returns a job ID that we can use to check the status of the transfer itself:

$ fts-transfer-status -d \
  -s https://fts3-public.cern.ch:8446 \
  247b7ca2-4c4d-11ec-84d0-fa163e5dcbe0
FINISHED

Step 5 Transfer between two object storage

We can also use the data transfer service to perform transfers between two object storage. In this case the transfer will be controlled by the FTS service you can use a command like:

$ fts-transfer-submit --s3alternate \
  -s https://fts3-public.cern.ch:8446 \
  s3://s3.cl2.du.cesnet.cz/bucket-name/1M.3 \
  s3://s3.cl2.du.cesnet.cz/bucket-name/A
c1d4a8e6-4c81-11ec-8926-fa163e5dcbe0

In this case too we can verify the status of the transfer with the same command as before using the new job ID.

$ fts-transfer-status -d \
  -s https://fts3-public.cern.ch:8446 \
  c1d4a8e6-4c81-11ec-8926-fa163e5dcbe0
FINISHED

Step 6 Web interface

An alternative way to check the status of the job is to use the FTS web interface to see using one the FTS servers and appending the job ID returned from one of the previous examples. For instance the link below will show the status of the specified job:

https://fts-public-003.cern.ch:8449/fts3/ftsmon/#/job/247b7ca2-4c4d-11ec-84d0-fa163e5dcbe0

WebFTS credential delegation

Last modified February 23, 2022 by Levente Farkas : Update user documentation structure (#414)