Update 2021-04-13T17:18:52+02:00: The server is now running again!
Thank you for your understanding.
The LDAP server is down and we are currently looking for a
solution. Since LDAP is used for authentification for portal, logins,
and SSH access to VMs, all accesses to these services are currently
blocked, even if VMs are still running. We hope that this problem will
be solved as soon as possible.
Thank you for your understanding!