ON any client host 
     You will have to source the client's profile

     source ~<clientUserID>/sqllib/db2cshrc
     eg: source ~db2leduc/sqllib/db2cshrc

     Issue the following Command

      % db2level
     

     DB21085I  This instance or install (instance name, where applicable: "db2cli") 
     uses "64" bits and DB2 code release "SQL10012" with level identifier 
     "0203010E".
     Informational tokens are "DB2 v10.1.0.2", "s121127", "IP23394", and Fix Pack 
     "2".
     Product is installed at "/cse/local/pkg/db2/V10.1".


    Using client db2c64

    DB21085I  Instance "db2c64" uses "64" bits and DB2 code release "SQL09017" with 
      level identifier "02080107".
     Informational tokens are "DB2 v9.1.0.7", "s090308", "MI00273", and Fix Pack  
     " 7".
     Product is installed at "/cse/local/pkg/db2/V9.1".