Dell Remote Access Card Console Redirection



Dell Remote Access Card

(DRAC) III Console Redirection

Enterprise Systems Group (ESG)

Dell OpenManage™

Systems Management

Dell White Paper

By Dung Nguyen

dung_nguyen@

Contents

Executive Summary 3

Introduction 4

Architecture 5

Seamless Operation 6

Multiple Client Access 6

Security 6

VNC Overview 7

Software Components 8

How To Setup and Use Console Redirection 9

Manual Device Driver and Services Install for Linux 7.1 9

Manual Device Driver and Services Install for Windows 2000 11

Performance 14

Console in Text Mode 14

Console in Graphic Mode 14

Troubleshooting 16

Conclusions 18

Related Web Sites for More Information 18

Tables

Table 1: Time to Update a Text Screen 14

Table 2: Mouse Movement Latency 15

Table 3: Time to Remotely Display a New Screen 15

Table 4: Properties with Default Values for Verification 16

Figures

Figure 1: Console Redirect Java Download and Initiation Sequence 5

Figure 2: VNC Server Software Enabling the Viewer 7

Section 1

Executive Summary

The DRAC III (Dell Remote Access Card) console redirection provides a powerful and rich feature set for Dell servers. It was developed mainly for system administrators who want to manage Dell servers remotely. This white paper provides a summary and detailed information about DRAC III console redirection architecture, implementation, and use under Microsoft® Windows® NT/2000, Novell® Netware® and Red Hat® Linux®. The three major features that DRAC III console redirection supports are:

• Text console redirection

• Graphic console redirection

• Keyboard and mouse redirection

Section 2

Introduction

The power of networking, the Internet, and the DRAC III console redirect features combined enable a systems administrator to manage servers remotely from a desktop or laptop computer. The servers to be managed can be located in the same building, in different buildings, in other cities, or even on the other side of the world.

The DRAC III console redirection features are designed to allow systems administrators to access a local server console remotely in both text and graphic mode. In text mode, a systems administrator can modify or change the server configuration via BIOS setup, or execute a DOS command if the server is running DOS. The expansion ROM options can also be selected or changed at power up if required. In graphic mode, the systems administrator can manage a server the same as if he or she were in front of the server. Currently, the DRAC III console redirection feature supports Windows NT and Windows 2000, Novell NetWare, and Linux operating systems.

Text mode has been commonly used for years to manage Unix servers across a network when the operating system (OS) is up and running. However, with increasing user demands and complex system configurations, the graphical user interface is preferable for managing a remote server, especially one installed with a Microsoft Windows operating system.

Section 3

Architecture

The DRAC III console redirect consists of both client and server functions that implement the redirection. The Console Redirect Server (CRS) is implemented in the DRAC III firmware, providing the server side of the console redirection feature. The client side of console redirection is implemented in the GUI Java. The Java client pulls the screen updates from the firmware server: when the user selects “console redirection” from the web graphical user interface (GUI), Java communicates with the DRAC III firmware. It receives the console screen information and then displays the screens in a dedicated console redirect window.

In a case where the server OS is down (i.e., when the server is booting), the firmware server gets the console data by reading the video controller frame buffer via PCI bus interface and sends the frame buffer to the Java-client for displaying in text mode. Once the OS is up and has changed the video controller into graphics mode, the firmware server simply acts as a proxy to relay the client requests for screen updates to the VNC (Virtual Network Computing) server on the managed node server, see Figure 1.

Figure 1: Console Redirect Java Download and Initiation Sequence

When the user first connects to the DRAC III, the DRAC III console loads to the browser from the DRAC III file system. After the user authenticates, the DRAC III console screen displays. From the main console screen the user may select the “console redirection” function to invoke the console redirect screen. The console redirect screen then runs in a separate window.

Seamless Operation

When the system is in non-graphics mode, it allows for seamless transition between text pre-boot screen and post-boot graphics screen. This means that a single window displays the text graphics during the boot and transitions to full graphics without the need for user interaction. The screen at all times displays a remote view of the primary monitor of the system. The window does not change in size or disappear during the boot transitions. Also, transitions between graphics mode and text mode are seamless, with the console redirection display in the same window and the same size.

Multiple Client Access

The DRAC III console redirection allows for multiple clients to redirect the console at the same time. Any of these users can input data as well as see the effect of other users’ inputs. (Note: The maximum number of users is stored in the property manager, with a default of four.)

Security

It is not possible to connect to the CRS from a client application that has not been authenticated with an encrypted password. The level of security necessary to establish a console redirect connection is equivalent to the level of security provided for the initial user authentication and command execution. That is, the difficulty of breaking-in with spoofing techniques must be equal to or greater than that required for initial authentication and command execution.

When the CRS connects to the managed node VNC server, it sends a standard VNC password (that is stored in the DRAC III firmware) to authenticate the connection. When the VNC password is changed in the DRAC III firmware property, an event is sent to the managed node along with the new encrypted password. The DRAC III service on managed node then updates the registry to synchronize with the DRAC III firmware.

Section 4

VNC Overview

VNC – Virtual Network Computing – is a remote display system that allows users to view and interact with a remote “desktop” using a very low-level graphics protocol that is platform-independent. Since VNC is a server-client software implementation, the VNC server software must be installed on the server side or the managed node to update the frame buffer displayed on the VNC client or viewer, see Figure 2. Dell has significantly modified the VNC client software, but not VNC server software, except for the port number. The modification is necessary to integrate with the main user interface. The authentication has been implemented in the DRAC III firmware rather than in the standard VNC Java client or viewer. This modification allows automatic authentication whenever the user clicks the console redirection button on the main user interface to launch the console redirect window.

[pic]

Figure 2: VNC Server Software Enabling the Viewer

VNC software was developed by AT&T and under General Public License (GPL). It is a very popular software package and has been used by many governmental, commercial, and educational organizations. Dell has chosen VNC for developing DRAC III console redirection because of its performance and maturity. The low cost (as a result of GPL) and fast time-to-market are also factors in using VNC.

VNC web site:

Section 5

Software Components

Brief descriptions of the basic software components that run on the managed node for using the DRAC III console redirection feature are as follow:

• DRAC III service

A service or daemon that runs on the managed node to allow the DRAC III firmware to communicate with the server.

• PPP protocol

A network TCP/IP communication protocol that requires the VNC server to send the updated screen to the client when a request is received from client.

• Virtual universal asynchronous receiver-transmitter (UART) device driver

The lowest level of software that runs on the operating system to allow the message to be sent and received to and from the DRAC III virtual UART.

• VNC server

A service or daemon that runs on the managed server to get the video frame buffer in order to send it to the client.

Please refer to the DRAC III user manual for reference to a complete installation of these software components on the managed node.

Section 6

How To Setup and Use Console Redirection

Setup and use of the DRAC III console redirection are designed to be easy with Dell’s installation CD. Please refer to the DRAC III user manual for normal installation and use of DRAC III console redirection. This section provides step-by-step instructions on how to install the DRAC III device driver and services or daemons manually for both Red Hat Linux 7.1 and Microsoft Windows 2000. These steps may be necessary to help ensure that all the software components are installed correctly.

Manual Device Driver and Services Install for Linux 7.1

1. Get the latest version of ./MN/Linux/PKG package from Source Safe.

2. Place all spec files in /usr/src/redhat/SPECS, then place all tar and patch files in /usr/src/redhat/SOURCES.

3. Make sure to convert these spec files to Unix file format by using "dos2unix [dosfile]" and by typing the following commands at Unix prompt “#”:

# dos2unix drscfirmware.spec

# dos2unix drsvnc.spec

# dos2unix drsc.spec

# cd /usr/src/redhat/SPECS

# rpm -ba drscfirmware.spec

# rpm -ba drsvnc.spec

# rpm -ba drsc.spec

These commands start the process that creates four rpm binaries /usr/src/redhat/RPMS and four rpm sources in /usr/src/redhat/SRPMS:

drsc-*.rpm

drsc-devel-*.rpm

drscfirmware-*.rpm

drsvnc-*.rpm

4. To install these files, type the following commands:

# rpm -ihv drsc-*.rpm

# rpm -ihv drsc-devel-*.rpm

# rpm -ihv drscfirmware-*.rpm

# rpm -ihv drsvnc-*.rpm

5. Make sure to convert all script files to Unix format:

# dos2unix /etc/ppp/peers/drsc

# dos2unix /etc/rc.d/init.d/drsc

# dos2unix /etc/sysconfig/drsc

# dos2unix /etc/rc.d/init.d/drsvnc

6. Manually start the PPP communication and VNC server:

# cd /etc/rc.d/init.d

# ./drsc load ; load virtual serial driver

# ./drsc start ; start PPP communication

# ./drsvnc start ; start VNC server

7. Manually install DRAC III virtual serial driver and scripts:

Input "ls /usr/modules" to find out the current kernel version, or use the command "uname -r", then type:

# cd /usr/src/redhat/BUILD/drsc-1.0.0/modules

# cp dial /etc/ppp/peers/drsc

# cp init.sh /etc/rc.d/init.d/drsc

# cp config /etc/sysconfig/drsc

# mkdir /lib/modules/2.4.3-5/misc

# cp drsc.o /lib/modules/2.4.3-5/misc

# cp drscser.o /lib/modules/2.4.3-5/misc

or modify config.mk to change the kernel version by using command "uname –r" then type:

# make install

Installed files:

/etc/sysconfig/drsc

/lib/modules/2.4.3-5/misc/drsc.o

/etc/ppp/peers/drsc

/etc/rc.d/init.d/drsc

/usr/share/man/man4/drsc.4

8. Install VNC server without verify package dependencies

# rpm -ivh --nodeps drsvnc-3.3.3r2-1.i386.rpm

Installed files:

/usr/sbin/drsXvnc

/usr/sbin/drsvncpasswd

/usr/sbin/drsserver

/etc/rc.d/init.d/drsvnc

/etc/sysconfig/drsvnc

/var/drsvnc/passwd

/var/drsvnc/drs.twmrc

9. Create/change VNC server password: default password = 123456

# /usr/sbin/drsvncpasswd /var/drsvnc/passwd

10. Use "chkconfig" to add/del/enable/disable a service or daemon:

(This process is done automatically by installing rpm package)

# /sbin/chkconfig --add drsvnc

# /sbin/chkconfig --del drsvnc

# /sbin/chkconfig --list | grep drs

For examples:

# chkconfig --list |grep drs

drsc 0:off 1:off 2:off 3:off 4:off 5:off 6:off

drsvnc 0:off 1:off 2:on 3:on 4:on 5:on 6:off

# chkconfig --add drsc

# chkconfig --list |grep drs

drsc 0:off 1:off 2:on 3:on 4:on 5:on 6:off

drsvnc 0:off 1:off 2:on 3:on 4:on 5:on 6:off

This process will create the links in rc.d directories to start or stop the service or daemon automatically at boot time.

Manual Device Driver and Services Install for Windows 2000

SP2.0 configuration space supports:

• PCI function 0: VGA Text Screen and mail box

• PCI function 1: VUART interface for PPP protocol

• PCI function 2: SMIC interface for SM interface software

1. Set up virtual UART driver:

• copy drscser.sys and drscser.inf to c:\winnt\system32\drivers

• go to Setting -> System -> Hardware -> Enable VUART (function 1)

• reboot computer

2. Set up PPP communication:

Control Panel -> Network and Dial-up Connections -> Make New Connection -> direct connection -> guest -> DRSCPORT

3. Set up WinVNC server:

Needed files:

• DRSWinVNC.exe

• omnithread_rt.dll

• VNCHooks_Settings.reg

• msvcrt.dll

• vnc.reg

• MSVCRTD.DLL

• VNCHooks.dll

Install WinVNC:

• C> DRSWinVNC -install

4. Set up WinVNC to run as a service:

Control Panel -> Administrative Tools -> Services -> Dell VNC Remote Service -> right click -> start

5. Set WinVNC password to run WinVNC as an application:

C> DRSWinVNC -run

Double click on VNC icon and set up the password.

6. Check to make sure RAS services are installed:

Control Panel -> Administrative Tools -> Services:

Remote Access Connection Manager

+ Telephony # Dependencies

+ Plug and Play

+ Remote Procedure Call (RPC)

Remote Access Auto Connection Manager

+ Remote Access Connection Manager # Dependencies

+ Telephony

+ Plug and Play

+ Remote Procedure Call (RPC)

7. Set up serial port to support RAS connection:

Control Panel -> Phone and Modem -> New -> Modem -> Add ->

Don't detect my modem; I will select it from a list -> Next ->

[Standard Modem Type] and Communications cable between two computers -> Next

Selected port: DRSCPORT

8. Set up DRSC service:

Needed files:

• drscdun.pbk

• drssrvc.exe

• libdrsc.dll

• libspcmp.dll

Install DRSC service:

• C> drssrvc -install

• C> drssrvc -h # for help

9. Set up WinVNC to run as a service:

Control Panel -> Administrative Tools -> Services -> Dell Remote Service -> right click -> start

10. Remove a service:

To remove a service, the service must first be disabled. Then reboot the system to remove it from the service manager window.

Section 7

Performance

Console in Text Mode

Dell measured three text console redirect parameters:

1. "Time to read video frame buffer" was measured by timing how long it took for the user interface (Java applet) to read a complete video frame buffer in raw format.

2. "Time to convert to ASCII format" was measured by timing how long it took to convert the video buffer in raw format to ASCII format for display.

3. "Time to draw the text" was measured by timing how long it took for the user interface (Java applet) to draw the text on the display.

Table 1 shows the time to update a complete text screen whenever the screen is changed in text mode.

|Description |Minimum |Maximum |Unit |

|Time to read video frame buffer |10 |921 |msec |

|Time to convert to ASCII format |0 |50 |msec |

|Time to draw the text |400 |541 |msec |

|Total time to complete a screen |410 |1512 |msec |

Table 1: Time to Update a Text Screen

The maximum time to refresh a text screen takes only 1.5 seconds.

Console in Graphic Mode

Two graphic console redirect parameters were measured:

1. Mouse movement latency

2. Time to remotely display a new screen

The mouse movement latency was measured by timing how long it took for the mouse pointer at the remote client and server to change to a new position after the remote mouse was moved. Two types of mouse movements were measured:

1. Short mouse movements (1-2 inches on a screen)

2. Long mouse movements (movements all the way across the screen)

The results presented in Table 2 show mouse movement latency, and the measurements shown here were repeatable and consistent.

|Mouse movement latency |

|Board |Short mouse movement |Long mouse movement |

|DRAC III |0.5 sec |1.0 sec |

Table 2: Mouse Movement Latency

Three types of “time to remotely display a new screen” were measured with several different standard Win2K screens:

1. Win2K standard desktop

2. My Computer

3. Internet Explorer

The time from screen selection via remote mouse double-click until the new screen was fully drawn on the remote browser was measured.

The "New desktop" refresh was measured from the time "console redirect" was clicked until the initial screen shows up. This includes the connect time as well as the screen refresh time. Once in console redirect, the "My Computer" and "Internet Explorer" screen display times are representative of additional screen refresh time.

The results presented in Table 3 show the time to remotely display a new screen, and the measurements shown here were repeatable and consistent.

|Time to remotely display a new screen |

|Board |New Desktop |My Computer |Internet Explorer |

|DRAC III |3.5 sec |0.8 sec |2 sec |

Table 3: Time to Remotely Display a New Screen

Section 8

Troubleshooting

To begin troubleshooting, the first step is to ensure that the managed node has all the necessary software that supports the DRAC III card installed. For console redirection, the DRAC III card must be installed in a slot on the same PCI bus as the video controller. Use the PCI bus software utilities to verify this configuration (i.e. “pview” or “pcitree”). Table 4 shows database properties with default values for verification.

|Database Property |Default Value |Comment |

|MANAGED_NODE_IP |192.168.234.235 |Managed node PPP IP address |

|VNC_SERVER_IP |0 |0=using PPP connection |

|VNC_MAX_USERS |4 |Maximum number of users |

|VNC_CLIENT_PORT |5900 |Client to DRAC III port number |

|VNC_SERVER_PORT |5981 |DRAC III to VNC server port number |

|VNC_SERVER_PW |123456 |VNC server password |

Table 4: Properties with Default Values for Verification

Note:

Change VNC_CLIENT_PORT property is required to reboot DRAC III card.

If VNC_SERVER_IP is 0, the VNC server IP is MANAGED_NODE_IP.

The VNC_SERVER_IP is used for testing purposes only.

• Text console redirection does not work:

Doing a hardware reset on the DRAC III card without rebooting MN (Managed Node) will cause the text console redirection to stop working. Software reset will not cause this problem.

• Console redirect frame shows "Please wait - initial screen loading" and stays in this mode forever when MN is up, VNC server is running, and PPP on MN is also running:

Possible problem: no connection between MN and firmware via PPP connection. Make sure MN can ping the firmware PPP IP address. To verify, open DOS window on MN and execute this command: C:\> ping 192.168.234.236 # ping DRAC III card via PPP connection, or telnet to firmware and execute command: ping 192.168.234.235.

If either one of the above executions work, the remote console should be visible. If it is impossible to ping the DRAC III card from MN with PPP IP address, rebooting MN without rebooting DRAC III firmware may correct this problem.

• Verify console redirection with the standard VNC viewer:

Run VNC viewer from MS and enter the MN IP address with port 5981.

For example: 143.166.157.78:5981, then enter the default password 123456.

This process verifies that the MN and VNC server are running properly.

• Bypassing the PPP connection by setting the VNC_SERVER_IP to MN IP address from GUI debug window:

This process can be used to verify that the PPP connection via MN asynchronous driver and the virtual UART in the DRAC III card are either working correctly or not. For example: d3debug propset VNC_SERVER_IP=143.166.157.78.

No need to reboot the DRAC III card when this property is changed.

• Remember to plug the AC adapter to the DRAC III card when testing under a Diamond system or any Dell system that will reset the PCI bus during a reboot of the OS.

Without the AC adapter or battery backup, the rebooting process will cause a disconnection between the current session and the connection from GUI (browser) to the DRAC III card and cause all kinds of Java exception errors. This also prevents the console redirection from switching from text to graphic mode.

• Alt+TAB key does not automatically update the screen.

The MN console screen displays correct information, but the remote console does not show the info. The work-around for this problem is to press the "Refresh" button on the console redirection window. Possible correction of this problem is to automatically refresh the screen when receiving this key.

• The message, "Warning: remote console is not available," indicates one of the following conditions:

▪ MN server is rebooting

▪ MN server screen is switching between text and graphic mode

▪ Communication has been dropped between the client (browser) and DRAC III card.

Action: either do nothing or re-start the console redirect window.

Section 9

Conclusions

The DRAC III console redirection feature allows systems administrators to access a local server console remotely in both text and graphic mode. Currently, the DRAC III console redirection feature supports Windows NT/2000, NetWare, and Linux operating systems.

The DRAC III console redirection is a must-have feature that will help cut product support costs down tremendously and increase the effectiveness of customer support.

Related Web Sites for More Information

• VNC Software:

• DRAC III Console Redirect Specification:

This White Paper is for informational purposes only. DELL MAKES NO WARRANTIES, EXPRESS OR IMPLIED, IN THIS WHITE PAPER. Dell cannot be responsible for errors in typography or photography.

Dell and PowerEdge are trademarks of Dell Computer Corporation. Microsoft and Windows are registered trademarks of Microsoft Corporation. Novell and Netware are registered trademarks of Novell Corporation. Red Hat is a registered trademark of Red Hat, Inc. Linux is a registered trademark of Linus Torvalds.

Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. Dell disclaims proprietary interest in the marks and names of others.

©Copyright 2002 Dell Computer Corporation. All rights reserved. Reproduction in any manner whatsoever without the express written permission of Dell Computer Corporation is strictly forbidden. For more information, contact Dell.

Information in this document is subject to change without notice.

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Figure 1

Firmware

Console Redirect Server

VNC server

Browser Java Console Redirection

Get text frame buffer

Video frame buffer

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