11th International dCache Workshop


We are happy to announce the 11th International dCache workshop, collocated with NeIC 2017 Conference in Umeå from 2017-05-29 to 2017-05-30.

As with earlier workshops, the dCache team is eager to maintain and strengthen the relationship to dCache system administrators, experienced or novice. Contributions to the workshop will focus on presenting mechanisms helping sysadmins to run secure and fault tolerant dCache systems. Furthermore, as usual, the team will elaborate on ongoing and future developments. In more detail:

As CEPH is becoming the standard for Object Storage Technologies, we’ll introduce CEPH as a backend storage system, operated underneath dCache version 3.0. First production experiences, tips and pitfalls will be presented.

Starting with dCache 3.0 sysadmins are enabled to build an almost fully fault tolerant dCache instance, surviving failure of a single arbitrary component. As a side effect, we will be able provide help on how to upgrade systems without downtime. Presentations will cover how to setup redundant core components and how to run those in a production environment.

During the workshop we will demonstrate on how a geographically highly distributed dCache installation can be sufficiently secured, even being operated over the public wide area internet. We’ll show on how to setup the inter-domain communication in a multi-site configuration and we will present the new “Tunnel auto-discovery mechanism” as well as configuration updates to the Zookeeper cluster.

In order to provide a consistent name space management, we extended the already presented RESTful interface to the dCache name space system. Besides a variety of new name space functions, calls have been added, allowing users to query and modify the Quality of the dCache Storage service provided by dCache itself and its custodial back-ends.

Last but not least, our graphical interface into the dCache namespace has been finalised. We’ll provide demos and instructions on how to enable and use the new ‘dCache-view’ component.

On top of those demos and presentations we’ll offer plenty of time for you to meet your colleague-sysadmins and of course the dCache developers, to discuss your experiences in running a dCache or to push for improvements simplifying your life or triggering new features for your storage customers.


Monday May 29

Tuesday May 30


Monday May 29

9:00 – 10:30 Parallel sessions

Coffee break 10:30 – 11:00

dCache tutorial

Introduction for new administrators.

Bring your site / dCache tune-up (dCache team)

A short session with dCache installation basics for newcomers. In parallel site admins can rise their problems which can be solved with the help of dCache developers and other admins.

12:30 – 13:30 Lunch

13:30 – 15:00


Sibel Yasar ~ 5 – 10 min

Introduction to workshop logistic, agenda and team.

dCache keynote

Patrick Fuhrmann ~ 10 min

High-level view of dCache; funding, projects, vision

DESY Cloud

Patrick Fuhrmann ~ 20 min

High level overview of dCache’s project status, its fundings, and the impact of modern storage technology on upcoming developments.

dCache new features overview

Patrick Fuhrmann ~ 20 min

A deeper dive into new features of the latest dCache versions and an outlook on upcoming functionalities.

dCache software, how you get it?

Sibel Yasar ~ 10 min

How and from where do I get my latest dCache release.


Tigran Mkrtchyan ~ 10 min

Current status of CEPH (free-software storage platform) integration with dCache. We’ll describe existing unctionality and first experience.

15:00 – 15:30 Coffee

15:30 – 17:00

What is HA dCache ?

Gerd Behrmann ~ 40 min

Starting with version 3.0, dCache supports high availability deployments. This allows central services to be scaled horizontally, provides fault tolerance for central services, as well as zero-downtime staged upgrades. Such a setup typically involves a redundant setup of ZooKeeper and PostgreSQL in addition to dCache, and typically relies on a redundant load balancer such as HAProxy.

NDGF HA current status

Mattias Wadenstein ~ 20 min

NDGF has used such a setup since fall 2016 and has build quite some experience with dCache HA. This talk will describe the concepts involved, give pointers on how to migrate existing setups towards HA in steps, as well as a short demo.

!!!! Hands-on while talking
Lightning talks

~ 30 min, 5 min each

This is a great opportunity for you to have a short, 5 min, presentation the areas you are using dCache for.

Tuesday May 30

9:00 – 10:30

NFS news

Tigran Mkrtchyan ~ 10 min

SAMBA news

Tigran Mkrtchyan ~ 10 min

dCache with Cloud backend

Tigran Mkrtchyan ~ 5 min

As being an industry standard, there are many players in the NFS protocol community. We will present the current state of the NFS protocol family, news from other vendors and dCache’s internal developments.

Securing dCache communications

Anupam Ashish ~ 20 min

  • cell communication (ssl)
  • Stunnel for zookeeper

Distributed dCache instances become increasingly attractive for geographically distributed installations. One of the aspects of such deployments is securing the inter-component communication. We will present how to run dCache in a distributed manner over wide area networks.

RESTful dCache

Marina Sahakyan ~ 40 min

  • QoS
  • Move to tape / move from tape

As we demonstrated during the Barcelona workshop, dCache has a new RESTful interface, providing direct access to the chimera namespace. This time we will present a set of new API calls to move files from/to a tape backend

REST API for Monitoring

Dmitry Litvintsev ~ 30 min

The RESTful interface is not only used for data management, but as well can be the source for a monitoring infrastructure. We will share our ideas on monitoring via the new RESTful interface and we will demonstrate the currently available functionality.

10:30 – 11:00 Coffee

11:00 - 12:30

dCache view

Olufemi Segun Adeyemi ~ 30 min

During last years workshop we introduced dCache-view, the component utilising the RESTful API to generate web pages for graphically uploading and downloading files and to manipulate their quality of service. This year we will elaborate on extended functionalities of that tool and on an enhanced look-and-feel.

Resilient dCache

Dmitry Litvintsev ~ 20 min

  • configuration examples (from user perspective)
  • ! resilient + tape for cloud at DESY

One of the ways to increase data resiliency in dCache is to keep multiple copies of precious files. In dCache this feature used to be provided by the Replica Manager. Based on a large set of new requirements by our customers it became necessary to redesign and improve this component now called Resilient Manager. We will demonstrate new and exciting features of this subsystem and will present a typical migration path from its predecessor.


Anupam Ashish ~ 40 min

With the increasing availability of automated computing platforms (PaaS) and scientific portals, allowing scientists to focus on their scientific work instead of forcing them to become an IT expert, storage systems are no longer directly accessed by processes under the control of the user but, instead, by a chain of intermediate agents. Consequently, when it comes to authorisation, the resource owner might have to grant permissions, on behave of the user, with narrowing privileges, along that chain. To enable infrastructures to tackle this issue, dCache is implementing Macaroons, a distributed authorisation method, introduced by Google. We will provide examples on how Macaroons have been integrated into dCache and how they can be used in complex computing and storage infrastructures.

12:30 – 13:30 Lunch

13:30 – 17:00


Marina Sahakyan & Anupam Ashish ~ 40 min

INDIGO-DataCloud (INtegrating Distributed data Infrastructures for Global Exploitation) is a European project in the framework of the H2020 program aiming to develope a data and computing platform targeting scientific communities, deployable on multiple hardware and provisioned over hybrid private or public e-infrastructures. This presentation will describe goals of the INDIGO-DataCloud and dCache’s involvement in terms of cloud storage and quality of service in storage.

The Book

Sibel Yasar ~ 10 min

Documentation is an essential component of any software product. Unfortunately, it’s always behind the actual development and is always out of date. To fix that issue, we decided to switch to an easy-to-use tool chain to allow internal and external contributors to update and publish the ‘dCache Admin Book’. We’ll present the tool and its workflow.


~ 30 min

This is our traditional open discussion about Life, the Universe and dCache.

15:00 – 15:30 Coffee

15:30 – 17:00

Bring Your Site (fixing sites)

dCache team

Site admins can raise their problems which are supposed to be solved with the help of dCache developers and other admins.

Workshop chair:
Sibel Yasar

  • Monday, May 29, 09:00 - 12:30 (Room: Grim)
  • Monday, May 29, 13:30 - 17:00 (Room: Grim)
  • Tuesday, May 30, 09:00 - 12:30 (Room: Grim)
  • Tuesday, May 30, 13:30 - 17:00 (Room: Grim)