Reference · RCC ClusterDocs

Which RCC connection name should I use?

Use the current RCC connection settings supplied through a trusted institutional channel. In these instructions, the connection name is rcc-login. Do not copy a server address from an old screenshot or a colleague's saved configuration.

Why the name stays the same

RCC aims to give users stable service aliases even when the physical or virtual systems behind them change. Operations may replace backends, storage gateways, jump hosts, or proxies while preserving an approved user-facing alias.

Stable service names must never be replaced in user documentation with physical infrastructure hostnames. Verify the approved RCC host identity through the current institutional connection instructions rather than accepting a changed key or copying an old configuration from a colleague.

Setup to use now

Use only values supplied by the approved RCC configuration:

Host rcc-login
    HostName VALUE_FROM_THE_APPROVED_RCC_CONFIGURATION
    User <RCC-USERNAME>
    IdentityFile ~/.ssh/id_rcc
    IdentitiesOnly yes
    ForwardAgent no

See Account access, SSH, and VS Code and the current institutional RCC connection instructions before changing an existing workstation configuration.

Names you may see in a saved configuration

Some saved workstation configurations contain login.ikim.uk-essen.de, shellhost, or shellhost.ikim.uk-essen.de. If you see one of these names, do not reuse it for a new connection. Get the RCC connection settings you should use now, test them, and only then remove the saved entry.

When reviewing a saved configuration:

1. identify which entries belong to RCC;
2. obtain the current RCC configuration through a trusted channel;
3. verify the published host identity independently;
4. test the approved alias with one bounded connection attempt; and
5. remove or archive superseded entries only after the replacement works.

Do not disable host-key checking, delete unrelated known_hosts entries, or replace a service alias with a physical node name.

During a backend maintenance window

RCC may move an approved connection alias between equivalent backends. An existing SSH or VS Code session can disconnect during that change. Reconnect with the same approved alias; do not create separate workstation targets for physical backend names. A diagnostic hostname value is not a connection name for users.

A timeout and a changed-host-key warning require different responses:

1. For a timeout, confirm the hospital network or VPN is available, then retry the same saved connection once.
2. For a changed-host-key warning, stop and contact RCC support through an official channel. Treat it as an infrastructure or security incident.

Never delete the complete ~/.ssh/known_hosts file, run a blanket ssh-keygen -R command, set StrictHostKeyChecking no or accept-new, or accept a replacement key merely to bypass the warning.

Transfer guidance

Service status: project Samba shares are ready now for approved projects and registered devices.

An approved SSH alias does not make SSHFS the preferred bulk-transfer method. Large instrument datasets should use the RCC files portal, approved SFTP, server-to-server transfer, Samba or facility-managed automated ingestion as appropriate. Use SSHFS only for light access to small files.