Obtaining and Renewing a CERN Grid Certificate in LHCb

Working with LHCb resources requires a valid grid certificate. Here’s a step-by-step guide for obtaining and renewing your certificate, tailored for lxplus and LHCb DIRAC access.

Obtaining a Certificate

Instructions: Official LHCb Certificate Guide

1. Use Firefox — Chrome and other browsers may not work well for certificate management.

2. Import all required certificates into Firefox (as described in the link above).

3. Import your personal certificate into Firefox. You’ll be prompted to set an import password—remember it!

4. Transfer the certificate to your lxplus account:

   scp MyCertificate.p12 <username>@lxplus.cern.ch:~
   

5. SSH into lxplus:

   ssh -Y <username>@lxplus.cern.ch
   

6. Convert the certificate to PEM format (you’ll be asked to set a PEM passphrase — use a different one than the import password):

   lb-dirac dirac-cert-convert MyCertificate.p12
   

7. Join the LHCb Virtual Organisation (VO) via the VOMS registration page. You may need to wait ~24 hours for validation.

8. Once validated, initialize your proxy on lxplus:

   lhcb-proxy-init
   

   Enter your PEM passphrase when prompted.

✅ You now have access to the LHCb DIRAC portal.

Renewing a Certificate

1. Download your renewed certificate from the CERN Certification Authority.

2. Transfer it to lxplus:

   scp NewCertificate.p12 <username>@lxplus.cern.ch:~
   

3. In Firefox, delete the old certificate and import the new .p12 one.

4. Update your IAM profile:
   • Visit IAM Profile
   • Under X.509 certificates, unlink the old certificate.
   • Then, link the new certificate you just imported.

5. On lxplus, clear your previous credentials:

   rm -rf ~/.globus
   

6. Convert the new certificate to PEM as before:

   lb-dirac dirac-cert-convert NewCertificate.p12
   

7. Test your setup: Follow this checklist to ensure everything is working.

8. Optionally run:

   lhcb-dirac
   

9. Finally, reinitialize your proxy:

   lhcb-proxy-init
   

✅ You have renewed your certificate.