va-scanCopyright 2002, Marchany Unit 2 – The Boot Prom – OpenBoot Randy Marchany VA Tech Computing Center

va-scanCopyright 2002, Marchany Introduction  OpenBoot is the firmware that controls the boot process of a Sun workstation.  It contains diagnostic commands that can help you determine HW configurations.  It is similar to the PC-BIOS of Intel platforms.  OpenBoot controls the monitor. It has no printscreen capability.

va-scanCopyright 2002, Marchany OpenBoot  OpenBoot commands can be entered directly from the system console or from a serial terminal connected to the TTYA or TTYB port on a Sparc workstation.  Press STOP-A to get in OpenBoot mode if using the monitor.  Press BREAK (CTRL-]) then ‘send break’ if connected through a telnet session.

va-scanCopyright 2002, Marchany OpenBoot  Initial output is a banner that describes the type of SPARC processor, OpenBoot version, memory size, Ethernet address.  Can be set up to boot automatically or wait for additional commands – type b (boot), c (continue) or n (new command mode) – b, c options go to Restricted Monitor mode – N selects full OpenBoot mode, prompt goes from > to OK. – Use the help command to get a full list of commands

va-scanCopyright 2002, Marchany OpenBoot Keyboard Commands ActionEffect STOP-AAbort the system STOPBypass POST STOP-DEnter diagnostic mode STOP-NReset NVRAM to defaults GoResume operation SyncSynchronize disk data

va-scanCopyright 2002, Marchany OpenBoot – Device Aliases  Sun hardware names are mysterious at best.  You can create aliases for these device names.  Common commands –.attributes – list device attributes –.properties – newer version of.attributes – cd – change directory – printenv – displays environment variables – setenv – set the environment variables – show-disks – list disk devices attached to system

va-scanCopyright 2002, Marchany OpenBoot  The “auto-boot?” environment variable tells OpenBoot to automatically boot the system after any failure if it’s set to TRUE.  Otherwise, the system will remain at the OK prompt until you manually enter the boot command.  OpenBoot builds a map of all devices connects to the system during boot. This is called a device tree.

va-scanCopyright 2002, Marchany OpenBoot Device Trees  The device tree describes all elements of the computer configuration.  Properties: characteristics of the device like its address  Methods: the commands you can issue that involve the device  Self-test: example of a method  Children/parent: describes the HW unit above and below the device

va-scanCopyright 2002, Marchany OpenBoot Device Tree  Top of the tree is the SPARC processor.  Next level: HW devices present on the motherboard – memory, bus (sbus or PCI), serial ports, keyboard, mouse, etc.  Next level: controller card attached to the bus (SCSI or PCI). The bus can have multiple controllers

va-scanCopyright 2002, Marchany OpenBoot Device Tree

va-scanCopyright 2002, Marchany OpenBoot Device Tree   - the Sbus address  - the external controller address  - the unit attached to the controller  Labels, sd, sd0, sd1 are usually SCSI disks.  Use an alias instead of this long name.

va-scanCopyright 2002, Marchany OpenBoot Device Aliases  nvalias command creates a device alias. – Syntax: nvalias alias-name real-device-name – Example: nvalias bigdisk  List all aliases with the.properties command  devalias command does the same thing but it’s temporary. Stays in effect until the next reset. Nvalias is the permanent command.