How to get the mode(Active-Passive) of each unit in Cluster(HA) system?

Using iControl?

I think this is what you want...

sub getFailoverState {
  my ($dbh, $dev)=(@_);
  my $t0=[gettimeofday];

  my $devID=$dev->{ID};
  my $devFQDN=$dev->{FQDN};
  my $icServer=$dev->{MgmtAddr};
  my $icPort=$dev->{MgmtPort};

  dbprint "getFailoverState: cookiejar (Before)\n";
  print Dumper($cookieJar);
  my $Failover =  SOAP::Lite
        -> uri('urn:iControl:System/Failover')
        ->     proxy("$sProtocol://$icUser:$icPass\@$icServer:$icPort/iControl/iControlPortal.cgi",     cookie_jar => $cookieJar);
        ->     proxy("$sProtocol://$icUser:$icPass\@$icServer:$icPort/iControl/iControlPortal.cgi"i,
  $Failover->transport->cookie_jar($cookieJar);

  dbprint "getFailoverState: Getting failover state for $devFQDN\n";

  my $soapResponse = $Failover->get_failover_state();

  dbprint "getFailoverState: cookiejar (After)\n";
  print Dumper($cookieJar);

  &checkResponse($soapResponse);
  my $failoverState=$soapResponse->result;

  dbprint "getFailoverState: state=$failoverState\n";

  my $updatestr="update device set fostate='$failoverState' where id=$devID";
  dbprint "getFailoverState: SQL [$updatestr]\n";
  my $update=$dbh->prepare($updatestr);
  $update->execute;

  my $elapsed=tv_interval ( $t0 );
  log_action($elapsed, 0, "getFailoverState", "$updatestr");
}