diff --git a/perl-xCAT/xCAT/DSHCLI.pm b/perl-xCAT/xCAT/DSHCLI.pm
index 80a2093b1..69d3c8cec 100644
--- a/perl-xCAT/xCAT/DSHCLI.pm
+++ b/perl-xCAT/xCAT/DSHCLI.pm
@@ -993,7 +993,7 @@ sub fork_fanout_dsh
                 #get user name and password  from the switches table
                  my $switchestab=xCAT::Table->new('switches',-create=>0);
 
-                 my $switchents = $switchestab->getNodesAttribs($targets_waiting,[qw/switch sshusername sshpassword/]);
+                 my $switchents = $switchestab->getNodesAttribs($targets_waiting,[qw/switch sshusername sshpassword protocol/]);
                  foreach my $entry (values %$switchents) {
                     my $switch=$entry->[0]->{switch};
                     if (defined($entry->[0]->{sshusername})) {
@@ -1002,6 +1002,9 @@ sub fork_fanout_dsh
                     if (defined($entry->[0]->{sshpassword})) {
                         $resolved_targets->{$switch}->{'password'}=$entry->[0]->{sshpassword};
                     }
+                    if (defined($entry->[0]->{protocol})) {
+                        $resolved_targets->{$switch}->{'remotecmdproto'}=$entry->[0]->{protocol};
+                    }
                 }
             }
         }
@@ -1076,6 +1079,9 @@ sub fork_fanout_dsh
                     $remote_shell = "$::XCATROOT/sbin/rshell_api";
                     $rsh_extension='RShellAPI';
                     $rsh_config{'password'}=$$target_properties{'password'};
+		    if ($$target_properties{'remotecmdproto'}) {
+			$rsh_config{'remotecmdproto'}=$$target_properties{'remotecmdproto'};
+		    }
                     if ($$options{'trace'}) {
 			$rsh_config{'trace'}=1;
 		    }
diff --git a/perl-xCAT/xCAT/Schema.pm b/perl-xCAT/xCAT/Schema.pm
index 446ea7782..e83fe89a8 100644
--- a/perl-xCAT/xCAT/Schema.pm
+++ b/perl-xCAT/xCAT/Schema.pm
@@ -591,7 +591,7 @@ noderes => {
  },
   },
     switches => {
-        cols => [qw(switch snmpversion username password privacy auth linkports sshusername sshpassword switchtype comments disable)],
+        cols => [qw(switch snmpversion username password privacy auth linkports sshusername sshpassword protocol switchtype comments disable)],
         keys => [qw(switch)],
         nodecol => "switch",
         table_desc => 'Parameters to use when interrogating switches',
@@ -603,8 +603,9 @@ noderes => {
          privacy => 'The privacy protocol to use for v3.  DES is assumed if v3 enabled, as it is the most readily available.',
          auth => 'The authentication protocol to use for SNMPv3.  SHA is assumed if v3 enabled and this is unspecified',
          linkports => 'The ports that connect to other switches. Currently, this column is only used by vlan configuration. The format is: "port_number:switch,port_number:switch...". Please refer to the switch table for details on how to specify the port numbers.',
-        sshusername => 'The user name for ssh. For Ethernet switches, it can be telnet username, use the format "tn:username" to indicate that it is for telnet.',
-        sshpassword => 'The password for ssh. For Ethernet switches, it can be password for telnet.',
+        sshusername => 'The remote login user name. It can be for ssh or telnet. If it is for telnet, please set protocol to "telnet".',
+        sshpassword => 'The remote login password. It can be for ssh or telnet. If it is for telnet, please set protocol to "telnet".',
+        protocol => 'Prorocol for running remote commands for the switch. The valid values are: ssh, telnet. ssh is the default. Leave it blank or set to "ssh" for Mellanox IB switch.',
         switchtype => 'The type of switch. It is used to identify the file name that implements the functions for this swithc. The valid values are: MellanoxIB etc.',
 	},
     },
diff --git a/xCAT-server/lib/perl/xCAT/RShellAPI.pm b/xCAT-server/lib/perl/xCAT/RShellAPI.pm
index 65feaa31f..85ef891d1 100644
--- a/xCAT-server/lib/perl/xCAT/RShellAPI.pm
+++ b/xCAT-server/lib/perl/xCAT/RShellAPI.pm
@@ -42,20 +42,12 @@ sub remote_shell_command {
 	if ( $$config{'trace'} ) {
 	    push @command, "-v";
 	}
+	if ( $$config{'remotecmdproto'} &&  ($$config{'remotecmdproto'} =~ /^telnet$/)) {
+	    push @command, "-t";
+	}
 	if ($$config{'user'} && ($$config{'user'}  !~ /^none$/i)) {
-	    my $username=$$config{'user'};
-	    my $telnet=0;
-	    if ($username =~ /^(tn:)(.*)$/) {
-		$telnet=1;
-		$username=$2;
-	    }
-	    if ($telnet) {
-		push @command, "-t";
-	    }
-	    if ($username) {
-		@tmp=split(' ', "-l $username");
-		push @command, @tmp;
-	    }
+	    @tmp=split(' ', "-l $$config{'user'}");
+	    push @command, @tmp;
 	}
 	if ($$config{'password'} && ($$config{'password'} !~ /^none$/i)) {
 	    @tmp=split(' ', "-p $$config{'password'}");
@@ -97,10 +89,12 @@ sub run_remote_shell_api {
     my $more_prompt='(.*key to continue.*|.*--More--\s*|.*--\(more.*\)--.*$)';
     my $output;
     my $errmsg;
+    my $ssh_tried=0;
 
     if (!$telnet) { 
 	eval {
 	    $output="start SSH session...\n";
+	    $ssh_tried=1;
 	    $t = new  xCAT::SSHInteract(
 		-username=>$user,
 		-password=>$passwd,
@@ -135,6 +129,9 @@ sub run_remote_shell_api {
 
     } else {
         #ssh failed.. fallback to a telnet attempt
+	if ($ssh_tried) {
+	    $output.="Warning: SSH failed, will try Telnet. Please set switches.protocol=telnet next time if you wish to use telnet directly.\n";
+	}
 	$output.="start Telnet session...\n";
 	require Net::Telnet;
 	$t = new Net::Telnet(