Re: Login with LDAP authentication takes 5 seconds

Achilleas Mantzios <achill@xxxxxxxxxxxxxxxxxxxxx> · Thu, 31 May 2018 17:54:50 +0300



    On 28/05/2018 17:26, Andreas Schmid
      wrote:

    
                        Hi,

                          
                        I configured my PostgreSQL 10 DB on Debian 9.2
                        with LDAP authentication (simple bind mode).
                        While this basically works, it has the strange
                        effect that the first login with psql takes
                        around 5 seconds. When I reconnect within 60
                        seconds, the login completes immediately.

                        
                      The LDAP server is behind a firewall. So for a
                      test, in pg_hba.conf I put the LDAP servers IP
                      address instead of its DNS name (for parameter
                      ldapserver). Like that, all logins complete
                      immediately. But in general I prefer specifying
                      the DNS name rather than the IP.

                      
                    When I checked on the DB machine with the following
                    commands

                  
                  host my.ldap.server.org

                
                dig my.ldap.server.org

                
                both always returned the host name and IP address of the
                LDAP server immediately. 

                
              Does anyone of you have an explanation for this, or a
              hint, where I could do some further investigation?

            
    IPv4 vs IPv6 ? any strange timeouts? look in the postgresql logs for
    any messages.

    Also definitely ran wireshark, it'll tell you a lot on what's
    happening between postgresql and your LDAP .
    
      
            Thanks,

          
          Andy

          
    -- 
Achilleas Mantzios
IT DEV Lead
IT DEPT
Dynacom Tankers Mgmt