custom glogin and RAC

I have used a glogin like the following for years. When I try to start svrctl with this, it looks for db name and username parameters and it fails to start. anyone know how to change this so I can make it work with RAC ?

  undefine usr db

          col usr new_value usr
          col db  new_value db

          set termout off
          select lower(user) usr,
                 substr(global_name, 1, instr(global_name, '.')-1) db
          from   global_name
          /
          set termout on

          set sqlprompt '&&usr.@&&db.> '

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