NAME

boot − Description of Sprite boot options and behavior

OPTIONS

There are a number of boot options that can be used to change the boot behavior. If you are unfamiliar with the booting process you should read the subsequent sections before this one. 

-cCauses a fileserver to ignore the existence of /bootTmp/boot and to boot as a dependent fileserver.  This is useful for booting fileservers with trashed disks. 

-fCauses a fileserver to boot without checking its disks.  This can lead to corrupted disks if the disks are not consistent before they are attached.  The -f option should not be used if the system halted abnormally. 

-sThe -s option causes the machine to boot in single-user mode.  A login shell is run by initsprite before both diskcmds and bootcmds.  Initsprite will continue when the login shell exits. 

-xIf the machine is a fileserver it will run /boot/rootcmds after running /boot/diskcmds.  This option allows a non-root fileserver to serve as root.  Only the root fileserver has the correct mount table for exporting "/" -- the rootcmds file contains the necessary commands for allowing a non-root fileserver to export "/". 

DESCRIPTION

The first couple sections of this man page are a user’s guide to booting Sprite.  Note that these are general instructions; each file server should have its specific booting instructions posted near its console. 

The rest of the man page goes into more detail about the boot process and is probably of interest only to people who hack Sprite. 

BOOTING SUNS

For all Suns except SPARCstation 2’s the boot command typed at the PROM has the format b xx(a,b,c)kernel [options]

For machines that are booted off of the network xx is usually ie or le, depending on whether the machine has an Intel or Lance ethernet chip.  For machines that boot off their disk, xx is usually sd.  For SPARCstation 2’s the boot command is b [device] kernel [options]

where device is usually net or disk.  (For SPARCstation 2’s running Sprite at Berkeley, device normally defaults to net.) 

The magic numbers a, b, c in parentheses are usually optional.  They specify information about the host that supplies the kernel (for booting off the net), disk partition, etc.  For network booting, the middle number is the last four digits of the IP address of the server.  You only need to specify this number if the default doesn’t work.  For example, to ensure that Murder boots off of Allspice (IP address 128.32.150.27), use b le(0,961b)sun3.md/sprite

and to boot off of Ginger (IP address 128.32.150.28), use b le(0,961c)sun3.md/sprite

The string kernel tells which kernel to load and boot.  When booting off a disk, kernel is usually just the name of the kernel, e.g., “new” or “sprite”.  When booting off the net, you must also specify the machine-dependent directory that the kernel is found in, e.g., “sun3.md/new”.  Use sun3.md for Sun 3’s, sun4.md for Sun 4’s, and sun4c.md for SPARCstation 1’s and 2’s. 

BOOTING DS3100’s

The basic boot command for a DECstation 3100 is boot -f proto()kernel [options]

where proto is either tftp or mop.  Generally mop is preferred, since it is faster and more reliable.  Unfortunately, it provides no feedback until the kernel starts running, so you have to put up with a 10-30 second pause before there’s any sign of life. 

The kernel string depends on whether the DECstation knows what server to use.  The simplest rule is to always type init to the PROM before booting, and use only the kernel name (e.g., “sprite” or “new”) for kernel.

BOOTING DS5000’s

The boot command for a DECstation 5000 looks like boot slot/xxx/kernel [options]

The slot string is the slot number for the device being booted from.  You can use the PROM’s cnfg command to get a list of what devices are installed at what slots.  Sprite DECstations typically have two ethernets installed; you should boot from the lower-numbered ethernet. 

The xxx string is the protocol type when booting from the net.  Use mop.  It is the disk name (e.g., “rz0”) when booting from the disk. 

The kernel string is just the name of the kernel (e.g., “new”). 

WHERE KERNELS LIVE

Machines that boot off of their own disk typically have a small boot partition, such as /allspiceA or /lustA.  In this case the kernel new would be installed as /allspiceA/new. 

Kernels that are downloaded from a Sprite server are installed in /sprite/boot (e.g., /sprite/boot/sun3.md/new). 

As a last resort kernels can also be downloaded from Ginger.  Those kernels are installed in /tftpboot (e.g., /tftpboot/sun3.md/new).  Suns that boot off of Ginger must have a link in /tftpboot to their boot program.  See the documentation for boot(8S) on Ginger. 

BOOT SEQUENCE

WARNING: This section is rather dated and is probably inaccurate in spots. 

This section outlines the sequence of events that occur during the boot process.  The command typed at the prom is used to start the downloader, then download the kernel from the server and start execution.  The early part of the boot is the same on all machines.  Kernel data structures are set up and kernel processes started.  Late in the boot the machine checks for the presence of a disk, and it starts the first user process initsprite.  The actions initsprite takes vary depending on the configuration of the machine.  There are three standard machine configurations.  Clients are diskless workstations.  They are dependent on the root fileserver to complete the boot process.  Machines with disks must check them during boot for inconsistencies.  Checking the disks requires the fscheck and fsattach programs, and related data files.  Standalone fileservers have these utilities on their own disk, and are therefore able to check their disks without the root fileserver.  Dependent fileservers have a disk, but it does not contain the needed files.  Dependent fileservers must get these files from the root file server. 

Clients
/boot/initsprite is exec’ed as the first user process. If "/" is unavailable the workstation will wait indefinitely, checking for "/" at 1 minute intervals. Initsprite will run /hosts/hostname/bootcmds if it exists and /boot/bootcmds otherwise. 

Dependent fileservers
Fileservers will detect the presence of a disk and attach it as "/bootTmp". This prefix is local to the machine and is not exported. If the directory /bootTmp/boot is not found, then the fileserver assumes it is a dependent fileserver. /boot/initsprite is exec’ed as the first user process. Initsprite will run /boot/diskcmds to verify that the disks are not corrupted. The table used to mount the disks is found in /hosts/$HOST/mount. Upon completion the machine will try to find a server of "/". If no server for "/" is found the workstation will retry at 1 minute intervals. Once a server is found, /hosts/hostname/bootcmds or /boot/bootcmds is run.  Initsprite will delete the "/bootTmp" prefix prior to exiting. 

Standalone fileservers
A standalone fileserver will attach its disk as /bootTmp and then check for /bootTmp/boot. Having found this directory it will create a new prefix "/" using the /bootTmp prefix. These prefixes are now synonyms and are local to the machine. The standalone fileserver can then proceed with the boot in the same manner as a dependent fileserver.  /boot/diskcmds is run. Unlike a dependent fileserver, /boot/diskcmds is on the machine’s own disk. The mount table is found in /hosts/$HOST/mount, also on the machine’s own disk. At some point in the boot the machine has to stop being its own server of "/" and look for the real server. This happens after diskcmds has been run. The machine will delete the "/" prefix and try to open "/". If the open fails the machine will try again at 1 minute intervals. Once "/" is found the appropriate bootcmds is run. Initsprite will delete the "/bootTmp" prefix prior to exiting.

FILES

/boot /boot is a directory that contains all of the files and utilities needed to boot a Sprite machine.  Standalone fileservers each have a /boot directory on their local disk and will use it during the boot process. 

/boot/cmds
Contains utility programs needed during boot.

/boot/diskcmds
Run by fileservers to check their disks. Note that dependent fileservers run the diskcmds found on the root fileserver.

/hosts/hostname/mount
The mount table read by fileserver hostname.  Standalone fileservers should have a copy of their mount table in /hosts/hostname/mount on both the local disk and the root fileserver. 

/boot/serverInfo
Provides machine name and type information to standalone fileservers. Standalone fileservers cannot depend upon the root fileserver being able to provide /etc/spritehosts (the usual place this information is found) so they need their own file.  The file should consist of the appropriate line from /etc/spritehosts.

/boot/bootcmds
This file is unique to the whole system. Standalone fileservers DO NOT look in their local /boot for this file. bootcmds contains commands for starting various user-level servers and other system configuration commands.

/hosts/hostname/bootcmds
If this file exists it is run instead of /boot/bootcmds.

/boot/rootcmds
This file contains the commands necessary for a backup root server to actually export root. In the normal case the file will contain the single line "prefix -x / -l /bootTmp".

KEYWORDS

boot, bootcmds, diskcmds, rootcmds
 

Sprite version 1.0  —  October 28, 1991