Cluster access

The only way to access the cluster is through the protocol SSH (Secure SHell). For this you can use one of the many available SSH clients:

  • for Windows: PuTTY (recommended client) or SecureCRT
  • for Unix/Linux: ssh (from the packet OpenSSH) or ssh2

The computational cluster has two front nodes to link to:

FQDN RSA fingerprint of the key DSA fingerprint of the key OS session port
physon.phys.uni-sofia.bg c0:1a:95:98:60:b7:e3:cd:ff:4c:86:4b:5f:84:60:bc 2c:c9:b4:a4:a2:b1:51:4f:2c:08:3a:d2:f1:bb:15:21 Ubuntu 8.04 LTS ssh/sftp 22
uspcc.phys.uni-sofia.bg 93:e1:aa:4d:14:83:1a:82:83:05:26:6d:5f:35:c2:a6 49:5d:54:50:e2:04:b4:bf:3d:87:aa:b0:ee:b6:e8:6a Ubuntu 12.04 LTS ssh/sftp 22
physon.phys.uni-sofia.bg af:a0:27:47:32:f0:3b:07:b8:d4:fe:c5:97:d9:6c:de 6c:f7:fa:be:7b:2e:4e:44:db:d0:9d:a1:87:6b:9a:e6 Ubuntu 11.10 nxclient 2022

Durring the first cluster connection SSH customers show the value of RSA fingerprint. Compare the displayed value with the one shown above – each difference indicates that a third party may interfere with the communication! The value may also be different if the server key is changed, which will be reflected in the news on the main page.

Q: When I try to connect in the cluster I get an error message that the protocol is not supported.

For security reasons, version 1 support of the SSH protocol is disabled. Some older clients only support version 1 and can not access the cluster. Update your client’s version or select version 2 of the protocol.

Question: SSH The session “dies” or interrupts after a few idle hours.

Access to the frontal node is via a rewrite system for network addresses. For security reasons, in the absence of traffic in either direction within two hours, links are automatically terminated. Please do not leave “hanging” terminals unattended!

Upload / download files

Access to the cluster file system is provided through the protocols SFTP or SCP. To do this, you can use one of the many SFTP / SCP clients:

  • for Windows: WinSCP (recommended client), FileZilla or pscp
  • for Unix/Linux: scp (from the packet OpenSSH or ssh2)

Access via NX client

The computational cluster allows remote access through an NX client when you want to run interactive sessions with X11 protocol support. For this purpose, you need to install NX client version 3.X, which can be downloaded from the following address:

Detailed instructions for setting up the NX session can be found in the following document