C H A P T E R 1 |
Configuring the System Console |
This chapter explains what the system console is, describes the different ways of configuring it on your server, and helps you understand its relation to the system controller.
Topics covered in this chapter include:
To install your system software or to diagnose problems, you need some way to interact at a low level with the system. The system console is Sun's facility for doing this. You use the system console to view messages and issue commands. There can be only one system console per computer.
The system console must be accessed through the system controller during initial system installation. After installation, you can configure the system console to accept input from and send output to different devices. TABLE 1-1 lists these devices and where they are discussed in the document.
A terminal server attached to the serial management port (SER MGT). |
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An alphanumeric terminal or similar device attached to the serial management port (SER MGT). |
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Accessing the System Console Through an Alphanumeric Terminal |
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A TIP line attached to the serial management port (SER MGT). |
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An Ethernet line connected to the network management port (NET MGT). |
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The system console displays status and error messages generated by firmware-based tests during system startup. After running those tests, you can enter special commands that affect the firmware and alter system behavior. For information about the tests that run during the boot process, refer to the service manual for your server.
Once the operating system is booted, the system console displays UNIX system messages and accepts UNIX commands. You can access the system console using the ALOM CMT console command.
The system controller console displays the results of the ALOM CMT boot diagnostics and initialization.
If it receives no user input within 60 seconds, ALOM CMT automatically connects to the system console. To return to the system controller, type the console escape sequence #. (Hash-Period).
To use the system console, you need to attach an I/O device to the system. Initially, you might have to configure that hardware, and load and configure appropriate software as well.
You must also ensure that the system console is directed to the appropriate port on your server's rear panel, generally, the one to which your hardware console device is attached (see FIGURE 1-1). You do this by setting the input-device and output-device OpenBoot configuration variables.
On your server, the system console comes preconfigured to allow input and output only by means of ALOM CMT. ALOM CMT must be accessed either through the system controller's serial management port (SER MGT) or the network management port (NET MGT). By default, the network management port is configured to retrieve network configuration using DHCP and to allow connections using SSH. You can modify the network management port configuration after connecting to ALOM CMT through either the system controller's serial or network management ports.
Typically, you connect one of the following hardware devices to the serial management port:
These constraints provide for secure access at the installation site.
Using a TIP line enables you to use windowing and operating system features on the system making the connection to your server.
The serial management port is not a general-purpose serial port. If you want to use a general-purpose serial port with your server, to connect a serial printer, for instance, use the regular 9-pin serial port on the rear panel of your server. The Solaris OS sees this port as TTYA.
Once the network management port (NET MGT) has been assigned an IP address by a DHCP server, you can connect to ALOM CMT using Secure Shell (SSH). As an alternative to the (default) DHCP configuration, you can configure the network management port with a static IP address, and change the communication protocol from SSH to Telnet. Up to eight simultaneous connections to the system controller sc> prompt are available through the network management port. For more information, see Activating the Network Management Port.
The following sections describe ways of accessing the system controller.
When you are accessing ALOM CMT using a device connected to the system controller's serial management port, you will see the output of the ALOM CMT diagnostics when AC power is first applied or when the system controller has been reset. After the diagnostics have completed the serial management port is available for login.
For more information about the system controller card, refer to the ALOM CMT guide for your server.
To Use the Serial Management Port |
1. Ensure that the serial port on your connecting device is set to the following parameters:
2. Establish an system controller session.
For instructions on how to use the system controller, see the ALOM CMT guide for your server.
The network management port is configured by default to retrieve network settings using DHCP and allow connections using SSH. You may need to modify these settings for your network. If you are unable to use DHCP and SSH on your network, you must connect to ALOM CMT through the system controller using the serial management port to reconfigure the network management port. See Using the Serial Management Port
You can assign the network management port a static IP address or you can configure the port to obtain an IP address using the Dynamic Host Configuration Protocol (DHCP) from another server. The network management port can be configured to accept connections from Telnet clients or SSH clients, but not both.
Data centers frequently devote a separate subnet to system management. If your data center has such a configuration, connect the network management port to this subnet.
To Activate the Network Management Port |
1. Connect an Ethernet cable to the network management port.
2. Log in to the system controller through the serial management port.
For more information about connecting to the serial management port, see Accessing the System Controller.
3. Type one of the following commands:
4. Type one of the following commands:
5. Reset the system controller so that the new settings take affect:
6. After the system controller resets, log in to the system controller and issue the shownetwork command to verify network settings:
To connect through the network management port, use the telnet or ssh (based on the value you provided in Step 4) commands to the IP address you specified in Step 3 of the preceding procedure.
The following procedure assumes that you are accessing ALOM CMT on the system controller by connecting a terminal server to the serial management port (SER MGT) of your server.
1. Complete the physical connection from the serial management port to your terminal server.
The serial management port on the server is a data terminal equipment (DTE) port. The pinouts for the serial management port correspond with the pinouts for the RJ-45 ports on the serial interface breakout cable supplied by Cisco for use with the Cisco AS2511-RJ terminal server. If you use a terminal server made by another manufacturer, check that the serial port pinouts of the server match those of the terminal server you plan to use.
If the pinouts for the server serial ports correspond with the pinouts for the RJ-45 ports on the terminal server, you have two connection options:
If the pinouts for the serial management port do not correspond with the pinouts for the RJ-45 ports on the terminal server, you need to make a crossover cable that takes each pin on the server serial management port to the corresponding pin in the terminal server's serial port.
TABLE 1-2 shows the crossovers that the cable must perform.
2. Open a terminal session on the connecting device, and type:
For example, for a server connected to port 10000 on a terminal server whose IP address is 192.20.30.10, you would type:
Use this procedure to access the server system console by connecting the serial management port (SER MGT) to the serial port of another Sun system (FIGURE 1-4).
1. Connect the RJ-45 serial cable and, if required, the DB-9 or DB-25 adapter provided.
The cable and adapter connect between another Sun system's serial port (typically TTYB) and the serial management port on the rear panel of the server. Pinouts, part numbers, and other details about the serial cable and adapter are provided in the service manual for your server.
2. Ensure that the /etc/remote file on the Sun system contains an entry for hardwire.
Most releases of Solaris OS software shipped since 1992 contain an /etc/remote file with the appropriate hardwire entry. However, if the system is running an older version of Solaris OS software, or if the /etc/remote file has been modified, you might need to edit the file. See Modifying the /etc/remote File for details.
3. In a shell tool window on the remote system, type:
The system responds by displaying:
The shell tool is now a TIP window directed to your server through the remote system's serial port. This connection is established and maintained even when the server is completely powered off or just starting up.
Note - Use a shell tool or a CDE terminal (such as dtterm), not a command tool. Some TIP commands might not work properly in a command tool window. |
This procedure might be necessary if you are accessing the server using a TIP connection from a remote system running an older version of the Solaris OS software. You might also need to perform this procedure if the /etc/remote file on the remote system has been altered and no longer contains an appropriate hardwire entry.
Log in as superuser to the system console of a system that you intend to use to establish a TIP connection to your server.
1. Determine the release level of Solaris OS software installed on the remote system. Type:
The system responds with a release number.
2. Do one of the following, depending on the number displayed.
The Solaris OS software shipped with an appropriate entry for hardwire in the /etc/remote file. If you suspect that this file was altered, and the hardwire entry modified or deleted, check the entry against the following example, and edit it as needed.
Note - If you intend to use the remote system's serial port A rather than serial port B, edit this entry by replacing /dev/term/b with /dev/term/a. |
Check the /etc/remote file and add the following entry, if it does not already exist.
Note - If you intend to use the remote system's serial port A rather than serial port B, edit this entry by replacing /dev/ttyb with /dev/ttya. |
The /etc/remote file is now properly configured. Continue establishing a TIP connection to the server system console. See TIP Connection Between a Server and Another Sun System.
If you have redirected the system console to TTYB and want to change the system console settings back to use the serial management and network management ports, see System Console OpenBoot Configuration Variable Settings.
Use this procedure when you access the server system console by connecting the serial port of an alphanumeric terminal to the serial management port (SER MGT) of the server.
To Access the System Console Through an Alphanumeric Terminal |
1. Attach one end of the serial cable to the alphanumeric terminal's serial port.
Use a null modem serial cable or an RJ-45 serial cable and null modem adapter. Connect this cable to the terminal's serial port connector.
2. Attach the opposite end of the serial cable to the serial management port on your server.
3. Connect the alphanumeric terminal's power cord to an AC outlet.
4. Set the alphanumeric terminal to receive:
Refer to the documentation accompanying your terminal for information about how to configure the terminal.
You can issue system commands and view system messages using the alphanumeric terminal. Continue with your installation or diagnostic procedure, as needed. When you are finished, type the alphanumeric terminal's escape sequence.
For more information about connecting to and using the system controller, refer to the ALOM CMT guide for your server.
The server features two management ports, labeled SER MGT and NET MGT, located on the server's rear panel. If the system console is directed to the virtual-console device (its default configuration), these ports provide access to both the system console and the ALOM CMT command-line interface (also called the system controller prompt, see FIGURE 1-5).
If the system console is configured to use the virtual-console device, when you connect through one of these ports you can access either the system controller prompt) or the system console. You can switch between the system controller prompt and the system console at any time, but you cannot access both at the same time from a single terminal or shell tool.
The prompt displayed on the terminal or shell tool indicates which channel you are accessing:
To reach the system console from the system controller prompt,
To reach ALOM CMT from the system console,
By default, the escape sequence is #. (Hash-Period).
For more information about communicating with the system controller and system console, see the following:
Advanced Lights Out Management (ALOM) CMT v1.3 Guide
The system controller runs independently of your server and regardless of system power state. When you connect your server to AC power, the system controller immediately starts up and begins monitoring the system.
Note - To view system controller boot messages, you must connect an alphanumeric terminal to the serial management port before connecting the AC power cords to the server. |
You can log in to the system controller at any time, regardless of system power state, as long as AC power is connected to the system and you have a way of interacting with the system. The sc> prompt indicates that you are interacting with the system controller directly. The sc> prompt is the first prompt you see when you log in to the system through the serial management port or network management port.
For more information about navigating between the system console and ALOM CMT (the system controller prompt), see the following:
Up to nine ALOM CMT sessions can be active concurrently, one session through the serial management port and up to eight sessions through the network management port. Users of each of these sessions can issue commands at the sc> prompt. For more information, see:
There are several ways to get to the sc> prompt:
The server with the Solaris OS installed is capable of operating at different run levels. A synopsis of run levels follows. For a full description of run levels, refer to the Solaris system administration documentation.
Most of the time, you operate the server at run level 2 or run level 3, which are multiuser states with access to full system and network resources. Occasionally, you might operate the system at run level 1, which is a single-user administrative state. However, the lowest operational state is run level 0. At this state, it is safe to turn off power to the system.
When your server is at run level 0, the ok prompt appears. This prompt indicates that the OpenBoot firmware is in control of the system.
There are a number of scenarios under which OpenBoot firmware control can occur.
It is the last of these scenarios which most often concerns you as an administrator, since there will be times when you need to reach the ok prompt. The section Methods To Reach the ok Prompt lists several ways. For detailed instructions, see Getting to the ok Prompt.
There are several ways to reach the ok prompt, depending on the state of the system and the means by which you are accessing the system console.
Note - These methods of reaching the ok prompt work only if the system console has been redirected to the appropriate port. For details, see System Console OpenBoot Configuration Variable Settings. |
A discussion of each method follows. For step-by-step instructions, see Getting to the ok Prompt.
The preferred method of reaching the ok prompt is to shut down the operating system by issuing an appropriate command (for example, the shutdown, init, or uadmin command) as described in Solaris system administration documentation. You can also use the system Power button to initiate a graceful system shutdown.
Gracefully shutting down the system prevents data loss, enables you to warn users beforehand, and causes minimal disruption. You can usually perform a graceful shutdown, provided the Solaris OS is running and the hardware has not experienced serious failure.
Typing break from the sc> prompt forces a running server to drop into OpenBoot firmware control. If the operating system is already halted, you can use the console command instead of break to reach the ok prompt.
Caution - After forcing the system into OpenBoot firmware control, be aware that issuing certain OpenBoot commands (like probe-scsi, probe-scsi-all, or probe-ide) might hang the system. |
When it is impossible or impractical to shut down the system gracefully, you can get to the ok prompt by typing the L1-A (Stop-A) key sequence from a keyboard connected to the server (that is, if OpenBoot input-device=keyboard). If you have an alphanumeric terminal attached to the server, press the Break key.
Caution - After forcing the system into OpenBoot firmware control, be aware that issuing certain OpenBoot commands (like probe-scsi, probe-scsi-all, or probe-ide) might hang the system. |
Use the system controller reset command, or poweron and poweroff commands, to reset the server. Reaching the ok prompt by performing a manual system reset or by power-cycling the system should be the method of last resort. Using these commands result in the loss of all system coherence and state information. A manual system reset could corrupt the server's file systems, although the fsck command usually restores them. Use this method only when nothing else works.
When you access the ok prompt from a functioning server, you are suspending the Solaris OS and placing the system under firmware control. Any processes that were running under the operating system are also suspended, and the state of such processes might not be recoverable.
After a manual system reset the system can be configured to boot automatically if the OpenBoot auto-boot? configuration variable is set to true. See System Console OpenBoot Configuration Variable Settings. If the server begins to boot automatically after a reset, you must abort the boot with the ALOM CMT break command or perform a graceful shutdown of the Solaris operating system once the boot has completed.
The commands you run from the ok prompt have the potential to affect the state of the system. This means that it is not always possible to resume execution of the operating system from the point at which it was suspended. Although the go command will resume execution in most circumstances, in general, each time you drop the system down to the ok prompt, you should expect to have to reboot the system to get back to the operating system.
For more information about the OpenBoot firmware, refer to the OpenBoot 4.x Command Reference Manual. An online version of the manual is included with the OpenBoot Collection AnswerBook that ships with Solaris software.
This procedure provides several ways of reaching the ok prompt. For details about when to use each method, see OpenBoot ok Prompt.
If at all possible, back up system data before starting this procedure. Also exit or stop all applications and warn users of the impending loss of service. For information about the appropriate backup and shutdown procedures, see Solaris system administration documentation.
To Get to the ok Prompt |
1. Decide which method you need to use to reach the ok prompt.
See OpenBoot ok Prompt for details.
2. Follow the appropriate instructions in TABLE 1-3.
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The server's system console is directed to the serial management and network management ports (SER MGT and NET MGT) by default.
Certain OpenBoot configuration variables control from where system console input is taken and to where its output is directed. The table below shows how to set these variables in order to use the serial management and network management ports.
The serial management port does not function as a standard serial connection. (If you want to connect a conventional serial device (such as a printer) to the system, you must connect it to TTYA not the serial management port.)
It is important to note that the sc> prompt and POST messages are only available through the serial management port and network management port.
In addition to the OpenBoot configuration variables described in TABLE 1-4, there are other variables that affect and determine system behavior. These variables are discussed in more detail in Appendix A.
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