Security

This section covers the security practices and procedures that all GridUnesp users must follow to protect their accounts, their data, and the integrity of the cluster as a whole.

Password Change

Importance of a Secure Password

Your password is the main barrier against unauthorized access to your account and to GridUnesp resources. A weak or shared password puts at risk not only your data but the entire cluster.

Characteristics of a strong password:

  • At least 8 characters (recommended: 12+)

  • Uppercase and lowercase letters

  • Numbers

  • Special symbols (!, $, %, @, #, etc.)

  • It must not be a common word, name, date, or obvious sequence

Examples:

  • ✅ Strong: M@t3m4t1c@_2025!

  • ✅ Strong: P3squ1s4#Gr1d

  • ❌ Weak: senha123

  • ❌ Weak: joao2024

  • ❌ Weak: abcdef

Warning

Never use the same GridUnesp password on other services (e-mail, social media, etc.).

How to Change Your Password

If you forgot your password or want to change it:

  1. Go to the page: https://www.ncc.unesp.br/password-new/

  2. Enter your registered username or e-mail

  3. A password-change token will be sent to your e-mail

  4. Follow the instructions in the e-mail to set a new password

Recommendations for regular changes:

After changing your password:

  • Update it in your SSH clients (if you saved the password)

  • Test the new access immediately

User Lockout (Fail2Ban)

What is Fail2Ban?

GridUnesp uses the Fail2Ban system for protection against brute-force attacks. This system monitors login attempts and temporarily blocks IP addresses that show suspicious behavior.

The system locks out the user for 15 minutes when:

  • The password is entered incorrectly multiple times

  • The scp command is used repeatedly in a short period

  • Multiple simultaneous logins are made from the same IP

  • Multiple connection attempts fail in a row

Identifying a Lockout

Typical lockout message:

ssh: connect to host access.grid.unesp.br port 22: Connection refused

How to confirm:

If you receive this message after several login attempts, you are probably locked out.

What to do:

  1. Wait 15 minutes and try again

  2. Do not keep trying during the lockout (it resets the counter)

  3. After 15 minutes, try again with the correct password

If the problem persists after 15 minutes:

# Run with debug output and send the output to support
ssh -vvv username@access.grid.unesp.br > debug_output.txt 2>&1

# Send the file debug_output.txt to support.ncc@unesp.br

Tip

To avoid lockouts, avoid multiple login attempts with the wrong password and do not overuse SCP commands in sequence.

Security Notification

Obligation to Report

Every user is required to immediately report to the GridUnesp team any suspected violation of the security rules.

Situations that must be reported:

  • Suspicion that your password has been compromised

  • Suspicious activity on your account (jobs you did not submit)

  • Files modified or deleted without your action

  • Strange messages or password requests

  • Any anomalous behavior in the system

Reporting channel:

support.ncc@unesp.br

Information to include:

  • Detailed description of the suspicion

  • Approximate date and time

  • Any available evidence (logs, messages)

  • Your username

Confidentiality

Important

Disclosing information about security incidents without prior authorization from the NCC is prohibited.

This includes:

  • Posts on social media

  • Discussions in public forums

  • Sharing with unauthorized people

Improper disclosure can:

  • Compromise ongoing investigations

  • Expose vulnerabilities to malicious actors

  • Harm the institution’s reputation

Privacy Policy

User Data

The NCC protects the privacy of all users. No inspection or examination of your files will be performed without:

  • Your explicit authorization

  • Authorization from the NCC Scientific Director

Exceptions:

  • Situations involving a compromise of system security

  • Well-founded suspicion of misuse of resources

  • A court order (very rare)

In these cases, access will be carried out in a controlled and documented manner, with the least possible interference.

Important

As explained in the Data Protection (LGPD) section, GridUnesp follows the guidelines of the General Data Protection Law (LGPD) - Law No. 13,709/2018 regarding users’ personal data.

Security Best Practices

Protecting Your Account

✅ Always:

  • Use strong, unique passwords

  • Change your password regularly

  • Log out at the end of your session

  • Periodically check your jobs (squeue -u $USER)

❌ Never:

  • Share your password with anyone (not colleagues, not advisors)

  • Write passwords in visible or insecure places

  • Use the same password on other services

  • Leave sessions open on shared computers

Security in Remote Access

On shared computers:

  • Always log out when finished

  • Do not save passwords in the browser or SSH client

  • Clear the command history if you typed the password (history -c)

On public networks:

  • Avoid connecting from open, insecure Wi-Fi networks

  • Use a VPN if available

  • Make sure the password-reset site is the official one (ncc.unesp.br)

On personal devices:

  • Keep your operating system up to date

  • Use antivirus/firewall

  • Encrypt your disk if possible

Phishing and Social Engineering

Beware of:

  • E-mails asking for your password (GridUnesp will never ask for your password by e-mail)

  • Suspicious links even if they look official (check the domain)

  • Urgent messages threatening to block your account

  • Offers of “help” to access your account

Always:

  • Check the e-mail sender

  • Confirm URLs before clicking (hover over the link)

  • When in doubt, contact support through the official channel

Activity Monitoring

Suspicious Jobs

Regularly check for jobs you did not submit:

squeue -u $USER
sacct -X -u $USER --starttime 2026-01-01

If you find suspicious activity:

  1. Immediately cancel unauthorized jobs: scancel JOBID

  2. Change your password immediately

  3. Report it to support with details

Recent Logins

Check when and from where your account was accessed:

last -n 20 $USER       # Last 20 logins
lastlog | grep $USER   # Last login

If you notice logins from unrecognized locations or times:

  1. Change your password immediately

  2. Report it to support

Physical Security

GridUnesp is located in the NCC Data Center, which has:

  • Biometric access control

  • 24/7 camera monitoring

  • Generators and UPS units

  • Fire extinguishers and fire-suppression systems

Visitor access is controlled and accompanied by authorized personnel.

Compliance with the Usage Policy

All users must know and comply with the Usage Policy. Non-compliance may result in:

  • Temporary suspension of the account

  • Permanent cancellation of the account

  • Reporting to the authorities in serious cases

Remember: The security of the cluster depends on the cooperation of all users. Be vigilant and report any anomaly.

See also