C&CZ

At the start of this year we installed a high-performance server (512 GB memory, two high-end GPUs). This machine now hosts local large-language models LLMs, meaning the AI runs entirely on‑premise and your data never leaves our network. What you can do today Access the web UI at chat.science.ru.nl. Log in with your Science RU username (e.g., jdoe, not jdoe@science.ru.nl). The service is powered by Ollama and Open WebUI, providing a clean, responsive chat interface. Early tests show reliable speech‑to‑text (including Dutch) and the ability to review source code. A user experience that feels very close to the larger commercial models, even though we are currently using open‑source models a few generations older. Current status - experimental We don’t know how many concurrent users the system can support and how much persistent storage will be required. No automated backups are in place; please treat the data you store there as temporary. Uptime is not guaranteed. The service may need to be restarted or the server rebooted when we apply configuration changes or updates. The setup will evolve as we gather feedback, so your input is valuable. Which models are available? Browse the full catalog on ollama.com/search. At the moment we run two gpt‑oss models, but many others can be added on request. ...

C&CZ was the first to implement e-mail (@sci.kun.nl) at the KUN (Katholieke Universiteit Nijmegen), some 35 years ago. Some configurations we have used since then have not kept up with the changing landscape of e-mail implementations worldwide. In Dutch there’s a saying for this: “De wet van de remmende voorsprong”. One of the major things that have changed over time is dealing with SPAM. For instance, there are now protocols that major e-mail players require and therefore became the de facto standard for email communication. ...

A new, for now experimental, feature is live on DIY, where you can “order” services directly by clicking the + on the right side. Ordering a product. This includes: Accounts: temporary logins, new groups, or guest accounts. Storage: new volumes or cloud endpoints on volumes. Email: create new aliases and mailman lists. Contact us: send an email to the helpdesk. Some services are directly provisioned, for others we still send an email to helpdesk@science.ru.nl where we need to implement the request manually. ...

Some websites under science.ru.nl may be inaccessible Several users have reported that they can no longer access websites such as http://example.science.ru.nl. Browsers block these connections because the parent domain ru.nl now requires HTTPS, while some websites, often served directly from devices or sensors, do not support encrypted connections. We are working on a general solution and will update this article once it becomes available. Background: HTTP Strict Transport Security (HSTS) Modern browsers enforce HTTP Strict Transport Security (HSTS) to prevent unencrypted HTTP access. Domains can opt in by being listed on hstspreload.org. Once listed, all subdomains must use HTTPS, and browsers will block HTTP entirely. ...

For years now Gitlab has bundled Mattermost as an integrated component for online chats, however this situation is changing, and Mattermost has announced that it is dropping support for single-sign-on (SSO). This is turn makes the integration with Gitlab unusable, thus Gitlab is now pondering dropping support altogether. This is unfortunate timing as we are working on tighter integration between science groups and Mattermost channels. Provisional Plan So what are we going to do about this? For chat, we have been looking at Zulip for a while now. This a stand alone, 100% open source chat server that works just like Mattermost. It’s supports OpenID, so we can hook up to diy for SSO. ...

Over the years we’ve had some requests to run an Overleaf instance for science users. To integrate this well in our environment we would need the enterprise version, which costs about € 8,- per user per month. This is prohibitive expensive for us to run, because we would need to pay for all science users, so we will not be pursuing setting up Overleaf any further in the science domain. There are alternatives for this setup, they may or may not work for your use case: ...

The latest version of Matlab, R2025b, is available. The software and license codes are directly available for Science accounts and can be requested by other entitled users by sending mail to the helpdesk. The software can also be found on the install-share. All C&CZ-managed Linux machines have this version installed, the older version (/opt/matlab-R2025a/bin/matlab) will be available temporarily. The C&CZ-managed Windows machines will not receive a new version during the semester to prevent problems with version dependencies in current lectures. ...

August 5th we had a cluster maintenance day, the next cluster maintenance window will be on February 6th 2026. We will do updates to packages and reboot the nodes. We plan to do this on all cnXXX nodes, mlpXX and comaXX nodes. We will not upgrade to a new version of ubuntu on this day, if you want your clusternodes to be upgraded, please arrange this seperately with us.

We have been working on replacing the old home servers home1 and home2 for some time now and a lot of our users have already been moved to the new home servers, home4, home5 and home6. If you login to dhz.science.ru.nl you can find your home volume path, for moved users this will look like \\306a2a9df234234123123523c22054dfaf9.home.science.ru.nl\loginname This path will not change in the future when we have to replace the home servers again. The first part is an alias for one of the new home servers. Every login will have an unique alias for its home path server. ...

The latest version of Matlab, R2025a, is available. The software and license codes are directly available for Science accounts and can be requested by other entitled users by sending mail to the helpdesk. The software can also be found on the install-share. All C&CZ-managed Linux machines have this version installed, the older version (/opt/matlab-R2024b/bin/matlab) will be available temporarily. The C&CZ-managed Windows machines will not receive a new version during the semester to prevent problems with version dependencies in current lectures. ...