PRACE Door Nodes are PRACE machines wich offer interactive access for all DECI users over the public Internet in order to reach all DECI resources on the dedicated PRACE network. The following table summarizes the PRACE Door Nodes together with the necessary details for the login.
Please take into consideration that SURFsara applies firewall restrictions to the public internet.
For access to the SURFsara doornode users are requested to send an e-mail to firstname.lastname@example.org and to provide their IP addresses for registration.
Once gained access, the proper PRACE and Globus environment should be setup. In order to do that, the following commands should be entered on the prompt line:
module load prace module load globus
Alternatively, both modules can be loaded using the following sequence:
module load prace globus
Only after issuing the module load globus command full access to the Globus client commands will be granted, such as GSI SSH. Other vital parameters that are needed to work with Globus are also set by ‘module load globus’, thus Globus commands will only work properly after this modulefile is loaded.
gsissh and GSISSH-Term automatically transfer proxy credentials to the target system, so that there is no need to type the passphrase a second time when using GSI SSH on the target machine to log into another remote machine. There is also no need to put grid credentials (usercert.pem and userkey.pem) directly on any PRACE machine. For security reasons it is advisable to keep the userkey.pem file only on the local workstation. $HOME file systems (or the $HOME/.globus directory) on PRACE supercomputers may be mounted via NFS and storing private keys on an NFS file system may violate the policy of the Certification Authority that issued the personal certificate.
If the door node is not the desired Execution Site, then the GSI SSH command line tool should be used from the door node to the Execution Site via the internal PRACE network. The prace_service tool can be very helpful in this case. It is a helper script coding the endpoints of Globus services on PRACE resources by means of mnemonic names and an .
A short usage guide is recalled typing on the prompt prace_service -h, showing the meaning of the available flags. A list of available sites together with their shortnames is recalled by entering prace_service -list
Putting all together, in order to hop to a certain PRACE site, the command to give is:
gsissh `prace_service -i -s <site>`
Please note that using the correct kind of inverted commas is essential.
For example, if CSC is the target, the command is:
gsissh `prace_service -i -s csc`
To query if an Execution Site offers the service required, a direct call to
prace_service -i -s <site> on the command line will return an error message in case of lack of support.