User Environment

A. Account Issuance

1. Researchers who are authorized to use the Neuron system can apply for an account via the KISTI homepage (https://www.ksc.re.kr) web service.

• Application method: Go to the homepage of the KISTI website. (Top) Apply for an account -> (Top) Apply -> Select an application

  • Free account: Nurion system innovation support program, novice users

  • Paid account: general users, student users

  • After the account is created, account-related information will be sent to the e-mail address provided in the application form.

2. OTP (One-Time Password) authentication code issuance

• Compose an email, as shown below, by referring to the email you received about the account information, and send it to [e-mail] to receive an authentication code.

Email subject	Request for an OTP authentication code - user ID (example) Request for an OTP authentication code - x123abc
Recipient	[e-mail]
Email content (example)	Login ID: x123abc Mobile phone number: 010-1234-5678 Name: Hong Gil-dong Network provider: LG U+ (or SKT/KT)

3. Install the OTP app

• The OTP smartphone app is provided for secure access to supercomputing resources.

• To use the OTP smartphone app, search for "Any OTP" in the Android app store (Google Play) or iPhone app store (App Store), and install the app developed by mirae-tech.

• When logging in to the supercomputer, you must enter the OTP security numbers from the “Any OTP” app.

※ For users who do not use smartphones, please contact the account administrator ([e-mail]).

※ Refer to the “OTP User Manual” at the KISTI homepage > Technical support > Guidelines for detailed method on how to install and use the OTP.

※ In the case of LG U+, text messages are processed as spam messages. Hence, information will be sent via email.

B. Login

• Users can gain access via the Neuron system’s login node (neuron01.ksc.re.kr, neuron02.ksc.re.kr). (refer to the node configuration below)

• The default character set (encoding) is Unicode (UTF-8).

• The login node can only be accessed using ssh, scp, sftp, or X11.

1. Unix or Linux environment

$ ssh -l neuron01.ksc.re.kr -p 22

• [-p 22]: specifies the port number and can be omitted

• Use the XQuartx terminal to run the X environment.

※ Download the program from the Internet for free, and then install it.

2. Windows environment

• Open Xming to run in the X environment.

※ Download the program from the Internet for free, and then install it.

• Use ssh connection programs, such as putty, Mobaxterm, or SSH Secure Shell Client.

  • Host Name: neuron.ksc.re.kr, Port: 22, Connection type: SSH

※ The programs can be downloaded from the Internet for free.

• ssh -> X11 tap -> check “Enable X11 forwarding”

• X display location: localhost:0.0

※ If you cannot connect owing to a DNS caching problem, clear the cache (run the ipconfig /flushdns command from the command prompt). Then, try to connect again.

C:￦> ipconfig /flushdns

3. Sending and receiving files

• Connect via ftp (can connect without OTP) or sftp using an FTP client, and send and receive files.

$ ftp neuron-dm.ksc.re.kr
or
$ sftp [user ID@]neuron-dm.ksc.re.kr [-P 22]

• Use a freely distributed FTP/SFTP client program, such as WinSCP, to connect in the Windows environment.

• Files can be sent without entering the OTP when using FTP (File Transfer Protocol).

• When using SFTP (Secure-FTP), the OTP must be entered to send files (a safer transmission method than FTP).

4. Node configuration

	Host Name	CPU Limit	Note
Login node	neuron.ksc.re.kr : Node with one V100 GPU card	120 minutes	• Can connect via ssh/scp • To compile and submit batch jobs • FTP/sftp not allowed
DM node	neuron-dm.ksc.re.kr	-	• Can connect via ftp

C. Changing User Shell

• The default shell provided by the login node of the Neuron system is the bash shell. To change to a different shell, use the chsh command.

$ chsh

• Use the echo $SHELL command to check the current shell being used.

$ echo $SHELL

• The shell environment can be configured by modifying the environment configuration file (e.g., .bashrc and .cshrc) in the user's home directory.

D. Changing User Password

• Use the passwd command from the login node to change the user password.

$ passwd

※ Password-related security policy

• The user password must be at least nine characters long and should consist of a combination of English alphabet letters, numbers, and special characters. The user password must not contain words from the English dictionary.

• The user password should be changed every 2 months (60 days).

• The new password cannot be similar to any of the most recent five passwords.

  • Maximum number of login failures allowed: 5 times

  • If an incorrect password is entered more than five times, the ID associated with this account becomes locked. To unlock the account, the user needs to contact the account administrator ([e-mail]).

• If the user tries to connect from the same PC and enters an incorrect password more than five times, the IP address of the PC becomes temporarily blocked. In this case, the user needs to contact the account administrator ([e-mail]).

  • Number of OTP authentication failures allowed: 5 times

• If the OTP authentication fails more than five times, the user needs to inquire with the account administrator ([e-mail]).

E. Time Allotted

Queue name (CPU type_GPU type_Number of GPUs)	Node name	Time allotted on the node per account	Hourly fee for using 1 node
cas_v100_2	gpu[30-44]	1000	1000 KRW
cas_v100nv_4	gpu[45-48]	600	1664 KRW
cas_v100nv_8	gpu[49-53]	300	3331 KRW
skl	skl[01-10]	4200	238 KRW
bigmem	bigmem01	7600	128 KRW
bigmem02	2200	454 KRW
amd	amd[01-02]	2500	397 KRW

※ Owing to the exclusive node policy, fees are charged for the total number of cores in at least one node.

F. Work Directory and Quota Policy

• The following is information about the home directory and scratch directory.

• The Neuron system does not support backup.

• Because the home directory has limited capacity and I/O performance, all computing jobs must be performed in the user workspace of the scratch directory (/scratch).

• Check the capacity of the user directory (run from the login node).

$ neuroninfo (or quotainfo)

• The file deletion policy(scratch purge policy) is applied based on the access time (atime) of the file attributes.

  • atime: the last time the file was accessed.

  • mtime: the last time the file's content was modified.

  • ctime: the last time the file's metadata (such as permissions, owner, or link count) was changed.

※ In the existing purge policy (files that have not been accessed for 15 days are automatically deleted), recovery of deleted files is basically impossible, but some changes are made to the purge policy to provide a grace period for users who forget to manage files. (2023.05. applied)

• After purging, the target file is prefixed with ToBeDelete_. Ex) ToBeDelete_file1.txt, ToBeDelete_file2.txt

  • If target file is needed, user must directly recover prefixed filename and update atime.

• After 30 days, files marked with ToBeDelete_ will be deleted in bulk, and the files cannot be recovered.

• The purge policy will be automatically performed on a regular basis once a month.

• atime can be checked with stat, ls -lu command, etc.

[login01 ~]# stat file1
File: ‘file1’
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: 805h/2053d Inode: 3221237903 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2022-04-05 08:52:30.113048319 +0900
Modify: 2022-04-05 08:52:30.113048319 +0900
Change: 2022-04-05 08:52:30.113048319 +0900$ lfs quota -h /scratch

$ ls -lu test.file
-rw-r--r-- 1 testuser testgroup 58 Jan 1 17:06  test.file

2023년 3월 16일에 마지막으로 업데이트되었습니다.