PLAN9.INI(8) PLAN9.INI(8)
NAME
plan9.ini - configuration file for PCs
SYNOPSIS
none
DESCRIPTION
When booting Plan 9 on a PC, the bootstrap programs
described in 9load(8) first read, via TFTP or a FAT filesys-
tem on the boot disk, a file containing configuration infor-
mation. This file, /cfg/pxe/hex-digits (TFTP; see 9load(8))
or plan9.ini (FAT), looks like a shell script containing
lines of the form
name=value
each of which defines a kernel or device parameter. Each
name assigned may be used as a variable in later defini-
tions. The special variables $bootdev and $bootpath are
assigned a value based on the device on which plan9.ini was
found. For example, to boot from kfs(4) on whichever device
plan9.ini was found
bootargs=local!$bootdev/fs
bootfile=$bootdev!9fat!9pccpu.gz
Blank lines and Carriage Returns (\r) are ignored. # com-
ments are ignored, but are only recognised if `#' appears at
the start of a line.
For devices, the generic format of value is
type=TYPE [port=N] [irq=N] [mem=N] [size=N] [dma=N] [ea=N]
specifying the controller type, the base I/O port of the
interface, its interrupt level, the physical starting
address of any mapped memory, the length in bytes of that
memory, the DMA channel, and for Ethernets an override of
the physical network address. Not all elements are relevant
to all devices; the relevant values and their defaults are
defined below in the description of each device.
The file is used by the bootstrap programs and the kernel to
configure the hardware available, although nowadays the ker-
nel can usually detect the attached hardware by itself. The
information it contains is also passed to the boot process,
and subsequently other programs, as environment variables
(see boot(8)). However, values whose names begin with an
asterisk `*' are used by the kernel and are stored in `#ec'
rather than `#e'.
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The following sections describe how variables are used.
ETHERNET
etherX=value
This defines an Ethernet interface. X, a unique monotoni-
cally increasing number beginning at 0, identifies an Ether-
net card to be probed at system boot. Probing stops when a
card is found or there is no line for etherX+1. After prob-
ing as directed by the etherX lines, any remaining Ethernet
cards that can be automatically detected are added. Almost
all cards can be automatically detected. For debugging pur-
poses, automatic probing can be disabled by specifying the
line `*noetherprobe='.
Many cards are software configurable and do not require all
options. Unspecified options default to the factory
defaults.
Known TYPEs are
igbe The Intel 8254X Gigabit Ethernet controllers, as
found on the Intel PRO/1000 adapters for copper (not
fiber). Completely configurable.
igbepcie
The Intel 8256[367], 8257[1-9], and 82580 Gigabit
Ethernet PCI-Express controllers. Completely con-
figurable.
rtl8169 The Realtek 8169 Gigabit Ethernet controller. Com-
pletely configurable.
ga620 Netgear GA620 and GA620T Gigabit Ethernet cards, and
other cards using the Alteon Acenic chip such as the
Alteon Acenic fiber and copper cards, the DEC
DEGPA-SA and the SGI Acenic. Completely config-
urable. Can't boot through these due to enormous
firmware loads.
dp83820 National Semiconductor DP83820-based Gigabit Ether-
net adapters, notably the D-Link DGE-500T. Com-
pletely configurable.
vgbe The VIA Velocity Gigabit Ethernet controller. Known
to drive the VIA8237 (ABIT AV8), but at 100Mb/s
full-duplex only.
m10g The Myricom 10-Gigabit Ethernet 10G-PCIE-8A con-
troller. Completely configurable.
i82598 The Intel 8259[89] 10-Gigabit Ethernet PCI-Express
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controllers. Completely configurable.
i82557 Cards using the Intel 8255[789] Fast Ethernet PCI
Bus LAN Controller such as the Intel EtherExpress
PRO/100B. Completely configurable, no options need
be given. If you need to force the media, specify
one of the options (no value) 10BASE-T, 10BASE-2,
10BASE-5, 100BASE-TX, 10BASE-TFD, 100BASE-TXFD,
100BASE-T4, 100BASE-FX, or 100BASE-FXFD. Completely
configurable.
2114x Cards using the Digital Equipment (now Intel) 2114x
PCI Fast Ethernet Adapter Controller, for example
the Netgear FA310. Completely configurable, no
options need be given. Media can be specified the
same was as for the i82557. Some cards using the
PNIC and PNIC2 near-clone chips may also work.
83815 National Semiconductor DP83815-based adapters,
notably the Netgear FA311, Netgear FA312, and vari-
ous SiS built-in controllers such as the SiS900. On
the SiS controllers, the Ethernet address is not
detected properly; specify it with an ea= attribute.
Completely configurable.
rtl8139 The Realtek 8139 Fast Ethernet controller. Com-
pletely configurable.
vt6102 The VIA VT6102 Fast Ethernet Controller (Rhine II).
vt6105m The VIA VT6105M Fast Ethernet Controller (Rhine
III).
smc91cxx
SMC 91cXX chip-based PCMCIA adapters, notably the
SMC EtherEZ card.
elnk3 The 3COM Etherlink III series of cards including the
5x9, 59x, and 905 and 905B. Completely config-
urable, no options need be given. The media may be
specified by setting media= to the value 10BaseT,
10Base2, 100BaseTX, 100BaseFX, aui, and mii. If you
need to force full duplex, because for example the
Ethernet switch does not negotiate correctly, just
name the word (no value) fullduplex or 100BASE-TXFD.
Similarly, to force 100Mbit operation, specify
force100. Port 0x110 is used for the little ISA
configuration dance.
3c589 The 3COM 3C589 series PCMCIA cards, including the
3C562 and the 589E. There is no support for the
modem on the 3C562. Completely configurable, no
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options need be given. Defaults are
port=0x240 irq=10
The media may be specified as media=10BaseT or
media=10Base2.
ec2t The Linksys Combo PCMCIA EthernetCard (EC2T), Ether-
Fast 10/100 PCMCIA cards (PCMPC100) and integrated
controllers (PCM100), the Netgear FA410TX 10/100
PCMCIA card and the Accton EtherPair-PCMCIA
(EN2216). Completely configurable, no options need
be given. Defaults are
port=0x300 irq=9
These cards are NE2000 clones. Other NE2000 compat-
ible PCMCIA cards may be tried with the option
id=string
where string is a unique identifier string contained
in the attribute memory of the card (see pcmcia(8));
unlike most options in plan9.ini, this string is
case-sensitive. The option dummyrr=[01] can be used
to turn off (0) or on (1) a dummy remote read in the
driver in such cases, depending on how NE2000 com-
patible they are.
ne2000 Not software configurable iff ISA; PCI clones or
supersets are software configurable; includes the
Realtek 8029 clone used by Parallels. 16-bit card.
Defaults are
port=0x300 irq=2 mem=0x04000 size=0x4000
The option (no value) nodummyrr is needed on some
(near) clones to turn off a dummy remote read in the
driver.
amd79c970
The AMD PCnet PCI Ethernet Adapter (AM79C970).
(This is the Ethernet adapter used by VMware.) Com-
pletely configurable, no options need be given.
wd8003 Includes WD8013 and SMC Elite and Elite Ultra cards.
There are varying degrees of software configurabil-
ity. Cards may be in either 8-bit or 16-bit slots.
Defaults are
port=0x280 irq=3 mem=0xD0000 size=0x2000
BUG: On many machines only the 16 bit card works.
sink A /dev/null for Ethernet packets - the interface
discards sent packets and never receives any. This
is used to provide a test bed for some experimental
Ethernet bridging software.
wavelan Lucent Wavelan (Orinoco) IEEE 802.11b and compatible
PCMCIA cards. Compatible cards include the Dell
TrueMobile 1150 and the Linksys Instant Wireless
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Network PC Card. Port and IRQ defaults are 0x180
and 3 respectively.
These cards take a number of unique options to aid
in identifying the card correctly on the 802.11b
network. The network may be ad hoc or managed (i.e.
use an access point):
mode=[adhoc, managed]
and defaults to managed. The 802.11b network to
attach to (managed mode) or identify as (ad hoc
mode), is specified by
essid=string
and defaults to a null string. The card station
name is given by
station=string
and defaults to Plan 9 STA. The channel to use is
given by
channel=number
where number lies in the range 1 to 16 inclusive;
the channel is normally negotiated automatically.
If the card is capable of encryption, the following
options may be used:
crypt=[off, on]
and defaults to on.
keyN=string
sets the encryption key N (where N is in the range 1
to 4 inclusive) to string; this will also set the
transmit key to N (see below). There are two for-
mats for string which depend on the length of the
string. If it is exactly 5 or 13 characters long it
is assumed to be an alphanumeric key; if it is
exactly 10 or 26 characters long the key is assumed
to be in hex format (without a leading 0x). The
lengths are checked, as is the format of a hex key.
txkey=number
sets the transmit key to use to be number in the
range 1 to 4 inclusive. If it is desired to exclude
or include unencrypted packets
clear=[off, on]
configures reception and defaults to inclusion.
The defaults are intended to match the common case
of a managed network with encryption and a typical
entry would only require, for example
essid=left-armpit key1=afish key2=calledraawaru
if the port and IRQ defaults are used. These
options may be set after boot by writing to the
device's ctl file using a space as the separator
between option and value, e.g.
echo 'key2 1d8f65c9a52d83c8e4b43f94af' >/net/ether0/0/ctl
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Card-specific power management may be
enabled/disabled by
pm=[on, off]
wavelanpci
PCI Ethernet adapters that use the same Wavelan pro-
gramming interface. Currently the only tested cards
are those based on the Intersil Prism 2.5 chipset.
yuk Some Marvell Yukon II 88e8057 chipsets. Completely
configurable. But not bootable due to missing 9load
driver.
DISKS, TAPES
(S)ATA and SAS controllers are autodetected.
usbX=type=uhci
usbX=type=ohci
usbX=type=ehci
This specifies the settings for a USB UHCI, OHCI or EHCI
controller. Like the Ethernet controllers, USB controllers
are autodetected after scanning for the ones listed in
plan9.ini. Thus, most systems will not need a usbX line.
Also like the Ethernet controllers, USB autoprobing can be
disabled by specifying the line *nousbprobe=.
scsiX=value
This defines a SCSI interface which cannot be automatically
detected by the kernel.
Known TYPEs are
aha1542
Adaptec 154x series of controllers (and clones).
Almost completely configurable, only the
port=0x300
option need be given.
NCR/Symbios/LSI-Logic 53c8xx-based adapters and Mylex Multi-
Master (Buslogic BT-*) adapters are automatically detected
and need no entries.
By default, the NCR 53c8xx driver searches for up to 32 con-
trollers. This can be changed by setting the variable
*maxsd53c8xx.
By default the Mylex driver resets SCSI cards by using both
the hard reset and SCSI bus reset flags in the driver inter-
face. If a variable *noscsireset is defined, the SCSI bus
reset flag is omitted.
aoeif=list
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This specifies a space-separated list of Ethernet interfaces
to be bound at boot to the ATA-over-Ethernet driver, aoe(3).
For example, `aoeif=ether0 ether1'. Only interfaces on this
list will initially be accessible via AoE.
aoedev=e!#æ/aoe/shelf.slot
This specifies an ATA-over-Ethernet device accessible via
the interfaces named in aoeif on AoE shelf and slot to use
as a root device for bootstrapping.
AUDIO
audioX=value
This defines a pre-USB sound interface.
Known types are
sb16 Sound Blaster 16.
ess1688 A Sound Blaster clone.
The DMA channel may be any of 5, 6, or 7. The defaults are
port=0x220 irq=7 dma=5
Uarts
Plan 9 automatically configures COM1 and COM2, if found, as
eia0 (port 0x3F8, IRQ4) and eia1 (port 0x2F8, IRQ3) respec-
tively. These devices can be disabled by adding a line:
eiaX=disabled
This is typically done in order to reuse the IRQ for another
device.
Plan 9 used to support various serial concentrators, includ-
ing the TTC 8 serial line card and various models in the
Star Gate Avanstar series of intelligent serial boards.
These are no longer supported; the much simpler Perle PCI-
Fast4, PCI-Fast8, and PCI-Fast16 controllers have taken
their places. These latter cards are automatically detected
and need no configuration lines.
The line serial=type=com can be used to specify settings for
a PCMCIA modem.
mouseport=value
This specifies where the mouse is attached. Value can be
ps2 the PS2 mouse/keyboard port. The BIOS setup procedure
should be used to configure the machine appropriately.
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ps2intellimouse
an Intellimouse on the PS2 port.
0 for COM1
1 for COM2
modemport=value
Picks the UART line to call out on. This is used when con-
necting to a file server over an async line. Value is the
number of the port.
console=value params
This is used to specify the console device. The default
value is cga; a number 0 or 1 specifies COM1 or COM2 respec-
tively. A serial console is initially configured with the
uart(3) configuration string b9600 l8 pn s1, specifying 9600
baud, 8 bit bytes, no parity, and one stop bit. If params
is given, it will be used to further configure the uart.
Notice that there is no = sign in the params syntax. For
example,
console=0 b19200 po
would use COM1 at 19,200 baud with odd parity.
PC CARD
pccard0=disabled
Disable probing for and automatic configuration of PC card
controllers.
pcmciaX=type=XXX irq=irq
If the default IRQ for the PCMCIA is correct, this entry can
be omitted. The value of type is ignored.
pcmcia0=disabled
Disable probing for and automatic configuration of PCMCIA
controllers.
NVRAM
nvram=file
nvrlen=length
nvroff=offset
This is used to specify an nvram device and optionally the
length of the ram and read/write offset to use. These val-
ues are consulted by readnvram (see authsrv(2)). The most
common use of the nvram is to hold a secstore(1) password
for use by factotum(4).
nvr=value
This is used by the WORM file server kernel to locate a file
holding information to configure the file system. The file
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cannot live on a SCSI disk. The default is fd!0!plan9.nvr
(sic), unless bootfile is set, in which case it is plan9.nvr
on the same disk as bootfile. The syntax is either
fd!unit!name or hd!unit!name where unit is the numeric unit
id. This variant syntax is a vestige of the file server
kernel's origins.
BOOTING
bootfile=value
This is used to direct the actions of the bootstrap programs
by naming the device and file from which to load the kernel.
rootdir=dir
rootspec=spec
These are used by the bootstrap programs to identify the
directory dir to make the root directory for the kernel, and
the file system specifier spec (see mount in bind(2)) on
which it can be found. These are usually used to test vari-
ant file systems for distributions, etc.
bootargs=args
The value of this variable is passed to boot(8) by the ker-
nel as the name of the root file system. It is typically
used to specify additional arguments to pass to kfs(4) or
ipconfig(8). For example, if the system is to run from a
local kfs(4) partition, the definition might read
bootargs=local!#S/sdC0/fs. See boot(8) for more.
nobootprompt=root
Suppress the `root from' prompt and use root as the answer
instead.
user=user
Suppress the `user' prompt and use user as the answer
instead.
debugfactotum=
Causes boot(8) to start factotum with the -p option, so that
it can be debugged.
factotumopts=options
Causes boot(8) to start factotum with the given options,
which must be a single word (i.e., contain no whitespace).
venti=value
When booting from a local fossil server backed by a local or
remote venti server, this variable specifies how to estab-
lish the connection to the venti server. See boot(8) for
more.
cfs=partition
This names the file holding the disk partition for the cache
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file system, cfs(4). Extending the bootargs example, one
would write cfs=#S/sdC0/cache.
bootdisk=value
This deprecated variable was used to specify the disk used
by the cache file system and other disk-resident services.
It is superseded by bootargs and cfs.
partition=value
This defines the partition table 9load(8) will examine to
find disk partitioning information. By default, a partition
table in a Plan 9 partition is consulted; if no such table
is found, an old-Plan 9 partition table on the next-to-last
or last sector of the disk is consulted. A value of new
consults only the first table, old only the second.
fs=a.b.c.d
auth=a.b.c.d
These specify the IP address of the file and authentication
server to use when mounting a network-provided root file
system. They are used only if the addresses cannot be
determined via DHCP.
PROCESSOR
*norealmode=
The PC kernel switches the processor to 16-bit real mode to
run BIOS interrupts, for example to find the memory map or
to enable VESA. This variable disables such switches.
*noe820scan=
When available, the PC kernel uses the BIOS E820 memory map
to size memory. This variable disables the scan.
*e820=
A space-seperated list of 3-tuples of ACPI memory type,
start address and end address generated at runtime by 9load
and iplpxe.
*maxmem=address
This defines the maximum physical address that the system
will scan when sizing memory. By default the PC operating
system will scan up to 3.75 gigabytes (0xF0000000, the base
of kernel virtual address space), but setting *maxmem will
limit the scan. *maxmem must be less than 3.75 gigabytes.
This variable is not consulted if using the E820 memory map.
*kernelpercent=percent
This defines the percentage of available memory reserved for
the kernel allocation pool. The remainder is left for user
processes. The default percent is 30 on CPU servers, 60 on
terminals with less than 16MB of memory, and 40 on terminals
with memories of 16MB or more. Terminals use more kernel
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memory because draw(3) maintains its graphic images in ker-
nel memory. This deprecated option is rarely necessary in
newer kernels.
*nomce=value
If machine check exceptions are supported by the processor,
then they are enabled by default. Setting this variable to
1 causes them to be disabled even when available.
*nomp=
A multiprocessor machine will enable all processors by
default. Setting *nomp restricts the kernel to starting
only one processor and using the traditional interrupt con-
troller.
*ncpu=cpus
Setting *ncpu restricts the kernel to starting at most cpus
processors.
*pcimaxbno=bno
Limits the maximum bus number probed on a PCI bus (default
255). This, and *pcimaxdno below are rarely used and only
on troublesome or suspect hardware.
*pcimaxdno=dno
Limits the maximum device number probed on a PCI bus
(default 31).
*nopcirouting=
Disable pci routing during boot. May solve interrupt rout-
ing problems on certain machines.
*nodumpstack=
Disable printing a stack dump on panic. Useful if there is
only a limited cga screen available, otherwise the textual
information about the panic may scroll off.
ioexclude=range
Specifies a list of ranges of I/O ports to exclude from use
by drivers. Ranges are inclusive on both ends and separated
by commas. For example:
ioexclude=0x330-0x337,0x430-0x43F
umbexclude=range
Specifies a list of ranges of UMB to exclude from use by
drivers. Ranges are inclusive on both ends and separated by
commas. For example:
umbexclude=0xD1800-0xD3FFF
apm0=
This enables the ``advanced power management'' interface as
described in apm(3) and apm(8). The main feature of the
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interface is the ability to watch battery life (see
stats(8)). It is not on by default because it causes prob-
lems on some laptops.
VIDEO
monitor=monitor
vgasize=xxyxd
These are used not by the kernel but by termrc (see
cpurc(8)) when starting vga(8).
*dpms=value
This is used to specify the screen blanking behavior of the
MGA4xx and Radeon video drivers. Values are standby,
suspend, and off. The first two specify differing levels of
power saving; the third turns the monitor off completely.
Multiple Configurations
A plan9.ini file may contain multiple configurations, each
within a block beginning with a line
[tag]
A special block with the tag menu gives a list of blocks
from which the user may interactively select the contents of
plan9.ini. There may also be multiple blocks with the tag
common which will be included in all selections; if any
lines appear in plan9.ini before the first block, they are
treated as a common block.
Within the menu block the following configuration lines are
allowed:
menuitem=tag[, description]
The block identified by tag will appear in the presented
menu. The menu entry will consist of the tag unless the
optional description is given.
menudefault=tag[, timeout]
Identifies a default block to be given in the menu selection
prompt. If the optional timeout is given (in seconds), the
default block will be selected if there is no user input
within the timeout period.
menuconsole=value options[, baud]
Selects a serial console upon which to present the menu as
no console options will have been processed yet (the
plan9.ini contents are still to be decided...). The depri-
cated baud option is accepted to assist older configura-
tions.
In response to the menu being printed, the user is prompted
to select a menu item from the list. If the numeric
response is followed by a p, the selected configuration is
printed and the menu presented again.
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The line
menuitem=tag
is prefixed to the selected configuration as an aid to
user-level initialization scripts.
EXAMPLES
A representative plan9.ini:
% cat /n/c:/plan9.ini
ether0=type=3C509
mouseport=ps2
modemport=1
serial0=type=generic port=0x3E8 irq=5
monitor=445x
vgasize=1600x1200x8
%
Minimum CONFIG.SYS and AUTOEXEC.BAT files to use COM2 as a
console:
% cat /n/c:/config.sys
SHELL=COMMAND.COM COM2 /P
% cat /n/c:/autoexec.bat
@ECHO OFF
PROMPT $p$g
PATH C:\DOS;C:\BIN
mode com2:96,n,8,1,p
SET TEMP=C:\TMP
%
Simple plan9.ini with multiple configurations:
[menu]
menuitem=vga, Plan 9 with VGA
menuitem=novga, Plan 9 no automatic VGA
menudefault=vga
[vga]
monitor=multisync135
vgasize=1024x768x8
[novga]
[common]
ether0=type=i82557
audio0=type=sb16 port=0x220 irq=5 dma=1
With this, the following menu will be presented on boot:
Plan 9 Startup Menu:
====================
1. Plan 9 with VGA
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2. Plan 9 no automatic VGA
Selection[default==1]:
Selecting item 1 generates the following plan9.ini to be
used by the remainder of the bootstrap process:
menuitem=vga
monitor=multisync135
vgasize=1024x768x8
ether0=type=i82557
audio0=type=sb16 port=0x220 irq=5 dma=1
and selecting item 2:
menuitem=novga
ether0=type=i82557
audio0=type=sb16 port=0x220 irq=5 dma=1
SEE ALSO
9load(8), booting(8), boot(8)
BUGS
Being able to set the console device to other than a display
is marginally useful on file servers; MS-DOS and the pro-
grams which run under it are so tightly bound to the display
that it is necessary to have a display if any setup or
reconfiguration programs need to be run. Also, the delay
before any messages appear at boot time is disconcerting, as
any error messages from the BIOS are lost.
This idea is at best an interesting experiment that needs
another iteration.
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