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This new procedure succeeds the GridKa CA and is in production! Requests to GridKa will be denied. It also holds for renewals of GridKa certs! For support please contact

Note: You will receive a Grid user cert with a different identity (DN) as before which must be added to your VO(s) (VOMS and/or DIRAC).



The German GridKa Certification Authority (CA) at KIT in Karlsruhe will cease operation at 11 June 2023 as the CA cert ends. As a successor the GÉANT Europe’s leading collaboration on network and related infrastructure and services for the benefit of research and education offers the services to obtain Grid user certificates starting now.


On order to access global Grid resources, users must hold a valid personal Grid user certificate (authentication) AND users must be member of a Virtual Organization (VO) (authorization).
A valid Grid user certificate is a prerequisite to request membership in a VO. Users usually have one Grid user certificate. Multiple VO membership is possible. A Grid user certificate can be seen as an analogy to a passport, whereas the VO membership compares to a visa.

The personal Grid user certificate is issued by a Certification Authority (CA). When certificates are requested the CA requires an authorization by the institution of the user against an Identity Provider (IdP).

A Grid user certificate (format X509) consists of a private key with a private password and a certified public key. The private key and the password is exclusively possessed by the user and is NOT known to the Registration Authority (RA) or Certification Authority (CA) at any stage.

A certificate is valid for one (1) year and can be renewed without changing the identity (DN). Users get notified by the CA via email three (3) weeks before the expiration date. It is strongly recommended to renew the certificate before its expiration.

The certificate can/should be copied to all devices/browsers which need it.


  • CA: Certification authority (issues certificates)
  • DN: Distinguished Name (identity of the user)
  • IdP: Identity Provider (service of an institution which knows its users)
  • IGTF: The International Grid Trust Federation (collection of known CAs)
  • OSG: Open Science Grid (the US Grid infrastructure)
  • SSO: Single Sign-On (unique user account at the institution)
  • VO: Virtual Organization (the collabration in the Grid)
  • VOMS: Virtual Organization management Service (a services to manage the VO members)
  • WLCG: Worldwide LHC Computing Grid (the HEP Grid infrastructure)


DESY users obtain personal Grid user certificates from the GÉANT CA. It is part of The International Grid Trust Federation (IGTF) hence certificates are accepted by all Grid sites in WLCG and OSG.

DESY / (UHH) employees may use their account to authenticate against GÉANT. Use the portal Certificate Manager SSO Check to test your account against the Identity Provider (IdP).

Non-DESY users can NOT use the portal and should check with their home institution officials how to proceed. The DFN Verein in Germany operates a CA. For the members of LHC experiments the CERN CA might be a good choice. Please also check EUGridPMA.


  1. Test your credentials (account_name / password) in Certificate Manager SSO Check against an Identity Provider (IdP). Select your home institution ('DESY' or '(UHH)').
    • if you encounter problems, please screenshot your status information in the SSO check portal for further debugging.
  2. Request a Grid user certificate in GEANT User Cert (attention: do not select the GEANT User Certificate or GÉANT IGTF-MICS-Robot Personal options but only GÉANT IGTF-MICS Personal).
    • profile: GÉANT IGTF-MICS Personal
    • chose: Key Generation
    • algorithm: RSA-4096


  3. After a short while the new cert can be downloaded from the page

    Usually, after requesting a certificate you will quickly receive a download link. However, depending on the load of the service the mail with the certificate download link it might take a bit longer.

  4. On Linux machines with Grid setups, the certificate and key files are usually placed in the directory ~/.globus/

    certificates and keys can occur in different formats (p12, pem), which can be converted from one to the other (see `Technicalities` below)

    1. Download certificate file and copy it to ~/.globus/usercert.p12
      1. if you use the default approach, the downloaded p12 file will contain both, the certificate and the key 
      2. the certificate is your passport, you "show" to services to authenticate yourself
    2. if you have generated the key file separately and copy as well the key file to ~/.globus/userkey.p12
      1. the key file is your secret key, that unlocks your certificate. Protect the key with a good password, do not share the key with anyone and backup the key, as it cannot be recovered, if the file got lost or you forgot the password
    3. optional: for usage in the Grid, you will have to convert the certificate+key from its "p12" file format into two "pem" formatted files: one file "usercert.pem" containing just the certificate and one file "userkey.pem", containing the password secured key. See 'Technicalities' below how to do it with openssl.
  5. Your user certificate (passport)  has to be registered at your experiment VO (VOMS). See links at the bottom.
    • If you have never registered before, go for it now.
    • A renewed certificate has the same DN. No action is needed if you had registered already.
    • A new certificate from a new CA contains a new DN:
      • Either add the new DN using your still valid already registered (old) certificate.
      • Or contact VO/VOMS admin to add the new DN to your VOMS record
  6.  Depending on your browser version, it might be necessary to check in your browser's certificate trust settings → the `The USERTRUST Network` certificate authority needs to be trusted for all operations

    • Firefox:

      • Settings → Privacy & Security → Certificates → View Certificates → Authorities
        in the `The USERTRUST Network` block, select `Edit Trust` if for `GEANT eScience Personal CA` and ensure, that all trust settings are enabled

    • Chrome
      • Settings → Security → Manage Certificates → Authorities
        search for `org-The USERTRUST Network` and ensure, that for both entries under `` → Edit all trust settings are selected

  7. To avoid problems with previous certificates, restart your browser after importing and backing up the certificate and key has been done. Always delete expired certificates!
    I.e., to quit Firefox or Chrome explicitly select `Quit` or `Exit`, respectively, from the browsers' menus.

    • if everything works with your new certificate, you should delete your previous certificate

Select your institution according to your affiliation. As of Mar 2022 we have seen successful request for:

  • Deutsches Elektronen-Synchrotron DESY (
  • Universität Hamburg (UHH) (

Check your the settings of your preferred email address if 

Preffered email
pal52: [~] ldapsearch -H ldap://it-ldap-slave:1389 -x -LLL -b 'ou=people,ou=rgy,o=desy,c=de' "(cn=first last)" mail 

As the DN of your certificate might  change, hence you might have to register the new DN with VOMS (and DIRAC etc.). This is most easy as long as your old/other certificate is still valid.

Browser Plugins and Extensions

If you encounter problems, please check if you have browser plugins or extensions enabled, that could interfere with the login and certificate & key generation.

For example, Chrome's automatic translation of web pages (German ↔ English) might result in unexpected behavior.

It is recommended to use a plain firefox.


Technically a new private/public key pair is created with every renewal while the DN stays the same!

Finding certificates in Firefox browser

Preferences -> Privacy & Security -> Certificates -> View Certificates -> Your Certificates (-> Backup)

Download/export the file either form the browser or directly to the ~/.globus/usercert.p12 directory and make sure to safe the old files. Then use openssl to extract ~/.globus/usercert.pem and ~/.globus/userkey.pem. Have your export passphrase at hand!

 > cd ~/.globus

 > mv usercert.p12 usercert.p12.old
 > mv usercert.pem usercert.pem.old
 > mv userkey.pem  userkey.pem.old

 > ls -l
-r-------- 1 account group 8213 24. Jan 14:36 usercert.p12
-r-------- 1 account group 2611 31. Jan 13:40 usercert.p12.old

 > openssl pkcs12 -clcerts -nokeys  -in usercert.p12 -out usercert.pem
 > openssl pkcs12 -nocerts          -in usercert.p12 -out userkey.pem

 > ls -l
-r-------- 1 account group 8213 24. Jan 14:36 usercert.p12
-r-------- 1 account group 8213 24. Jan 14:38 usercert.pem
-r-------- 1 account group 2611 31. Jan 13:42 userkey.pem

Importing certificates into Firefox browser

Preferences -> Privacy & Security -> Certificates -> View Certificates -> Your Certificates (-> Import)

Lost private/public keys or the password can NOT be recovered by any means by the CA or RA.
Please back up certificates and keys in a safe manner.

It is the 'usercert.p12' which you distribute to your browsers of choice even on other hosts.

The two extracted '~/.globus/user*.pem' files must be present on all hosts you use Grid commands on!

Keep the key file userkey.pem save - it is the key to unlock your usercert.pem certificate. Do not share the key file with anyone and secure it with a good password!

Known Issues

  • Make sure to export the certificate from the browser you requested and retrieved it with in as 'usercert.p12'.
  • Make sure you remember the pass-phrase for the key and for the export.
  • Make sure your have 'usercert.pem' and 'userkey.pem' in the direcory ~/.globus/
  • Make sure the access permissions to 'usercert.pem' and 'userkey.pem' are correct.
  • We found that a cert did now work with 'voms-proxy-init' although everything had been checked. Only a new extraction from  the exported cert 'usercert.p12' helped.

Inspecting Grid user certificates

Please make sure your public (usercert.pem) and private (userkey.pem) keys are:

  • in the correct directory,
  • have the correct permissions,
  • show your DN,
  • are valid,
  • match each other (have the same md5sum),
  • your remember the password.
 > cd ~/.globus

 > ls -l
-r--r--r-- 1 account group  1728  8. Apr 09:36 usercert.pem
-r-------- 1 account group  2012  8. Apr 09:36 userkey.pem

 > openssl x509 -subject -issuer -dates -noout -in usercert.pem
subject= /DC=org/DC=terena/DC=tcs/C=DE/O=Deutsches Elektronen-Synchrotron DESY/CN=Andreas Gellrich
issuer= /C=NL/O=GEANT Vereniging/CN=GEANT eScience Personal CA 4
notBefore=Jan 24 00:00:00 2022 GMT
notAfter=Jan 24 23:59:59 2023 GMT

 > openssl x509 -noout -modulus -in usercert.pem | openssl md5
 > openssl rsa -noout -modulus -in userkey.pem   | openssl md5

List of VOMS Servers

The obsolete documentation for the previous Grid user certificates from GridKa CA can be found under [ Grid User Certificates Old ]- intended just for historic reference.

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