Error while trying to connect to the computer

New to AiiDA
1

Hi everyone,

I am trying to connect to HPC,from my local computer.
My computer.yaml looks the following:

label: lanlhpc 
description: LANL
hostname: ch-fe.lanl.gov 
transport: core.ssh
scheduler: core.slurm
work_dir: "/lustre/scratch5/rkarkee/aiida_run" 
mpirun_command: "srun -n {tot_num_mpiprocs}" 
mpiprocs_per_machine: 256

Then I did

(aiida) rkarkee@RKARKEE:~$ verdi computer setup --config computer.yaml
Report: enter ? for help.
Report: enter ! to ignore the default and set no value.
Shebang line (first line of each script, starting with #!) [#!/bin/bash]:
Default amount of memory per machine (kB).: 51765
Escape CLI arguments in double quotes [y/N]: y

Select an editor.  To change later, run 'select-editor'.
  1. /bin/nano        <---- easiest
  2. /usr/bin/vim.basic
  3. /usr/bin/vim.tiny
  4. /bin/ed

Choose 1-4 [1]: 1
Success: Computer<1> lanlhpc created

Then

(aiida) rkarkee@RKARKEE:~$ verdi -p rkee computer configure core.ssh lanlhpc
Report: enter ? for help.
Report: enter ! to ignore the default and set no value.
User name [rkarkee]: rkarkee
Port number [22]:
Look for keys [Y/n]:
SSH key file []:
Connection timeout in s [60]:
Allow ssh agent [Y/n]:
SSH proxy jump []:
SSH proxy command []:
Compress file transfers [Y/n]: y
GSS auth [False]:
GSS kex [False]:
GSS deleg_creds [False]:
GSS host [ch-fe.lanl.gov]:
Load system host keys [Y/n]:
Key policy (RejectPolicy, WarningPolicy, AutoAddPolicy) [RejectPolicy]:
Use login shell when executing command [Y/n]:
Connection cooldown time (s) [30.0]:
Report: Configuring computer lanlhpc for user rijankarkee@gmail.com.
Success: lanlhpc successfully configured for rijankarkee@gmail.com

Then when I test it, I got

(aiida) rkarkee@RKARKEE:~$ verdi computer test lanlhpc
Report: Testing computer<lanlhpc> for user<rijankarkee@gmail.com>...
* Opening connection... Error: Error connecting to 'ch-fe.lanl.gov' through SSH: [SshTransport] [Errno -2] Name or service not known, connect_args were: {'username': 'rkarkee', 'port': 22, 'look_for_keys': True, 'key_filename': '', 'timeout': 60, 'allow_agent': True, 'proxy_jump': '', 'proxy_command': '', 'compress': True, 'gss_auth': False, 'gss_kex': False, 'gss_deleg_creds': False, 'gss_host': 'ch-fe.lanl.gov'}
[FAILED]: Error while trying to connect to the computer
  Use the `--print-traceback` option to see the full traceback.
Warning: 1 out of 0 tests failed

I am not sure how do I connect to HPC. I am also wondering when connecting to HPC, will it ask me to enter password? I am not sure how will this work. Can I get help on connecting HPC so that I can run my calculations on HPC rather than on computer.

Thank you

Best
Rijan

2

As the error says:

you are not able to connect to the machine ch-fe.lanl.gov; “Name or service not known” means the that hostname ch-fe.lanl.gov is either incorrect or you can connect to it only from within some private network.

You should first manage to connect via regular SSH, following the instructions of your center (LANL), without password (i.e. with a SSH key). We cannot help for this as we do not know how LANL supercomputers are setup.

Once you manage to do this from the command line, report how you connect and we can help setting up correctly your computer setup/configuration.

3

Hi @giovannipizzi
I can always connect to ssh myusername@ch-fe.lanl.gov (without needing dedicated network).
The password is through a token so it is always changing.
So you’re suggesting to login via SSH key without a password here. That I need to check with the IT team.