Terms of Usage

Last updated: October 2026

The ICARUS | NTUA High-Performance Computing Infrastructure ("ICARUS") provides shared CPU, GPU, and storage resources for research, teaching, and academic software development at the National Technical University of Athens (NTUA). By accessing and using ICARUS, users agree to comply with these Terms of Usage, applicable NTUA rules, and the conditions of their approved projects and allocations.

1. Access and Projects

Access is organized through approved projects, each with a responsible principal investigator (PI) or project lead, authorized members, an allocation, and an expiry date. Signing in to the User Dashboard does not by itself grant access to compute resources.

Faculty members may submit proposals through an applicable academic call. Students and researchers may join approved projects when an authorized project manager or administrator adds them.
Users must sign in using their own authorized institutional or separately issued ICARUS account. Accounts, passwords, private SSH keys, and other credentials must not be shared.
Project managers and administrators are responsible for assigning appropriate roles, maintaining accurate project membership, and removing access when it is no longer needed.
Users must notify ICARUS support promptly if they suspect their credentials have been compromised or that unauthorized access has occurred.

The current call allows up to four projects per PI, subject to the applicable review process and any approved exceptions. The standard project duration is six months. Extensions or additional resources require a justified request and approval; an application or extension request does not itself extend access.

See Access to the User Dashboard, Calls and Project Proposals, and Project Administration.

Project members share the resources assigned to their project. Users must request only the resources their jobs need, monitor usage, and comply with the approved allocation, applicable service policies, and expiry date.

CPU resource use is accounted for in core-hours. One CPU core-hour is one allocated CPU core for one hour.
GPU usage is reported in equivalent core-hours, according to the conversion and accounting rules of the ICARUS offering. CPU cores and GPUs are not interchangeable units; consult the offering and dashboard usage report when estimating charges.
Jobs must be submitted through Slurm with the appropriate project account. Users must not circumvent scheduling, accounting, quota, or access restrictions.

The currently documented Standard compute tier (standard Slurm QoS) has these per-job limits:

Limit	Maximum per job
Compute nodes	8
Requested walltime	72 hours
Nodes × requested walltime	72 node-hours

The 72 node-hour limit applies to each job, not to the total project allocation. Other allocation-wide restrictions may also apply. These limits do not reserve dedicated nodes or guarantee an immediate job start. Jobs are scheduled according to resource availability, fair-sharing priorities, and other Slurm policies.

See Compute Tiers, Job Accounting, and Check Usage. The applicable approved allocation and published service policies govern if limits change.

3. Responsible Use and Security

Users must:

Use ICARUS for their approved academic or research purposes and comply with applicable laws, NTUA regulations, software licences, intellectual-property requirements, and project conditions.
Respect the confidentiality and access rights of other users, projects, and research groups.
Keep credentials and SSH private keys secure, use their own accounts, and report suspected security incidents through ICARUS support.
Use login nodes for interactive access, data transfer, compilation, and preparation. Run demanding computational workloads on compute nodes through Slurm, not on login nodes.
Transfer datasets and software through approved access points; compute nodes do not provide general internet access.

The following activities are prohibited unless explicitly authorized where authorization is relevant:

Sharing accounts or accessing systems or data without permission.
Evading resource limits, interfering with scheduling, weakening security controls, or disrupting other users or services.
Cryptocurrency mining, unlawful activity, or commercial or personal-profit use outside the scope of an approved allocation.
Unauthorized network scanning, attempts to compromise systems, or other activity that threatens the security or reliability of the infrastructure.

4. Research Data and User Responsibilities

Users and project leads are responsible for deciding whether they are permitted to upload and process their research data on ICARUS. They must obtain any necessary permissions, licences, ethical approvals, and data-protection arrangements before using the service.

Research data may contain confidential information or personal data relating to research participants or other individuals. Before uploading sensitive, regulated, or otherwise restricted datasets, the project lead must confirm that the proposed processing is permitted and that the infrastructure and any required safeguards are appropriate. Where clarification is needed, contact ICARUS support and, for personal-data matters, the NTUA Data Protection Officer.

Users must not attempt to access or disclose another project's files without authorization. Project managers should grant membership only to people who require access and review it when their responsibilities change.

5. Service Availability and Maintenance

ICARUS is a shared research infrastructure. Scheduled maintenance, security measures, equipment failures, power or network incidents, and other operational events may delay, interrupt, or terminate jobs or temporarily restrict access.

Users should plan for interruptions, use application checkpointing where appropriate, retain copies of important data outside ICARUS, and monitor notices about maintenance or service changes. An approved allocation does not guarantee uninterrupted availability or specific job start times.

6. Storage Quotas, Backups, and Data Retention

The currently documented storage allowances are:

Storage area	Current quota
User home directory	25 GB per user
Project scratch directory	2 TB per project, shared by its members

Storage quotas also include applicable file-count limits. Reaching a storage or file-count limit may prevent further writes, including job output. Membership in additional projects does not increase an individual's home quota or combine different projects' scratch quotas.

User data is not backed up. ICARUS is not an archival storage service. Users must maintain independent copies of files they need to preserve and transfer them before their access expires.

Under the current Data Retention Policy:

Project scratch data is deleted three months after the project ends.
User home data is deleted after six months without membership in any project.

A storage-retention period does not extend compute access or guarantee continued SSH or login access. Users should arrange data transfers before the project or their access expires, not wait for the deletion deadline. Deleted data may not be recoverable.

These file-retention rules are separate from the retention of account, administrative, usage, and audit records, which is described in the Privacy Policy.

7. Enforcement and Changes to Access

The ICARUS infrastructure team administers the service. Where reasonably necessary to protect users, data, equipment, or the service, or to address suspected violations of these Terms, authorized administrators may restrict access, pause or cancel jobs, or suspend accounts or allocations.

Where practicable and appropriate, affected users or project leads will be informed and may contact ICARUS support for clarification. Immediate action may be necessary to contain a security incident or operational risk. NTUA rules and applicable law continue to apply.

8. Research Outputs and Acknowledgment

Users should acknowledge ICARUS in publications, theses, presentations, and other research outputs that relied on its resources. Suggested wording:

This work was supported by the ICARUS HPC Infrastructure of the National Technical University of Athens.

When requested for an allocation review or renewal, project leads should provide a short account of the resource usage, work performed, and research outcomes.

9. Support and Policy Updates

For access, project, allocation, software, storage, or infrastructure issues, submit a support ticket through the ICARUS User Dashboard. If you cannot sign in, ask your project lead or manager to report the access issue on your behalf.

These Terms may be updated to reflect changes to the service, resources, NTUA rules, or applicable law. The current version will be published with the ICARUS documentation. Users should also consult the conditions of their approved allocation and the current service policies.

For information on the processing of personal data, see the Privacy Policy.