PLAN9.INI(8) PLAN9.INI(8)
NAME
plan9.ini - configuration file for PCs
SYNOPSIS
none
DESCRIPTION
When booting Plan 9 on a PC, the bootloader program 9boot(8)
first reads configuration information from a file on the
boot media. This file, plan9.ini, looks like a shell script
containing lines of the form
name=value
each of which defines a kernel or device parameter.
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 kernel to configure the hardware
available. The information it contains is also passed to
the boot process, and subsequently other programs, as envi-
ronment variables (see boot(8)). However, values whose names
begin with an asterisk * are used by the kernel and are not
converted into environment variables.
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
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purposes, automatic probing can be disabled by specifying
the line *noetherprobe=.
Some 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[36], 8257[12], and 82573[ev] 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.
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. Can't boot
through these due to enormous firmware loads.
i82598 The Intel 8259[89] 10-Gigabit Ethernet PCI-Express
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.
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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).
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
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
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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.
bcm Broadcom BCM57xx Gigabit Ethernet controllers. Com-
pletely configurable, no options need be given.
yuk Marvell 88e8057 Yukon2 Gigabit Ethernet controller.
Completely configurable, no options need be given.
virtio Virtual Ethernet interface provided by QEMU/KVM and
VirtualBox. No options need be given. The MAC
address can be changed with the ea= option.
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
Network PC Card. Port and IRQ defaults are 0x180
and 3 respectively.
These cards take a number of unique options to aid
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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
Card-specific power management may be
enabled/disabled by
pm=[on, off]
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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.
iwl Intel Wireless WiFi Link mini PCI-Express adapters
require firmware from
http://firmware.openbsd.org/firmware/*/iwn-firmware*.tgz
to be present on attach in /lib/firmware or /boot.
To limit the selected APs the options essid= and
bssid= may be set at boot or in the ether interface
clone file using a space as the separator between
option and value, e.g.
echo essid left-armpit >/net/ether1/clone
Scan results appear in the ifstats file and can be
read out like:
cat /net/ether1/ifstats
Ad-hoc mode or WEP encryption is currently not sup-
ported.
rt2860 Ralink Technology PCI/PCI-Express wireless adapters
require firmware from
http://firmware.openbsd.org/firmware/*/ral-firmware*.tgz
to be present on attach in /lib/firmware or /boot.
See iwl section above for configuration details.
wpi Intel PRO Wireless 3945abg PCI/PCI-Express wireless
adapters require firmware from
http://firmware.openbsd.org/firmware/*/wpi-firmware*.tgz
to be present on attach in /lib/firmware or /boot.
See iwl section above for configuration details.
wpapsk=password
WPA/WPA2 encryption is detected automatically and a prompt
for the password will appear when using the WIFI interface
for netbooting. To avoid the prompt, the password can be
specified with the boot parameter above.
nora6=
Disable automatic IPv6 configuration from incoming router
advertisements.
DISKS, TAPES
(S)ATA controllers are autodetected.
*nodma=
disables dma on ata devices.
*sdXXdma=on
explicitly enables dma on a specific ata device.
scsiX=value
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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
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.
ramdiskX=size
ramdiskX=size sectorsize
ramdiskX=address size sectorsize
This reserves physical memory as a ramdisk that will appear
as sd(3) device sdZX. When the address argument is omited
or zero, then the ramdisk will be allocated from the top of
physical memory.
AUDIO
audioX=value
This defines a sound interface. PCI based audio devices such
as Intel HD audio or AC97 are autodetected and do not
require any settings.
Known types are
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hda Intel HD audio.
ac97 AC97 based card.
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.
Additional i8250 (ISA) uarts (uart2 to uart5) can be config-
ured using:
uartX=type=isa port=port irq=irq
Perle PCI-Fast4, PCI-Fast8, and PCI-Fast16 controllers 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.
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
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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.
The value net specifies ``netconsole'' which sends console
messages as UDP packets over the network. It bypasses the
IP stack and writes Ethernet packets directly to the NIC.
In this case params is mandatory and takes the form
srcip [ !srcport ] [ /devno ] , dstip [ !dstport ] [
/dstmac ]
Srcip, srcport (default 6665), dstip and dstport (default
6666) specify the source IP address, source port, destina-
tion IP address and destination port, respectively. Devno
(default 0) specifies which NIC to use, a value of n corre-
sponds to NIC at #ln (see ether(3)). Dstmac specifies the
destination MAC address; broadcast packets are sent if it is
unspecified. Note that it is possible, but not recommended,
to send packets to a host outside the local network by spec-
ifying the MAC address of the gateway as dstmac. Example
lines are
console=net 192.168.0.4,192.168.0.8
console=net 192.168.2.10!1337/1,192.168.2.3!1337/0ea7deadbeef
PC CARD
pccard0=disabled
Disable probing for and automatic configuration of PC card
controllers.
pcmciaX=type=XXX irq=value
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.
BOOTING
bootfile=value
This is used to direct the actions of 9boot(8) by naming the
file from which to load the kernel in the current BIOS boot
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device.
bootargs=value
The value of this variable is passed to boot(8) by the ker-
nel as the name of the root file system to automatically
mount and boot into. It is typically used to specify addi-
tional arguments to pass to cwfs(4) or ipconfig(8). For
example, if the system is to run from a local cwfs(4) parti-
tion, the definition might read
bootargs=local!/dev/sdC0/fscache. See boot(8) for more.
nobootprompt=value
Suppress the `bootargs' prompt and use value as the answer
instead.
rootdir=/root/dir
rootspec=spec
Changes the mount arguments for the root file server that
was specified by bootargs above. By changing dir in
$rootdir, a different sub-directory on the root file server
can be used as the system root. see boot(8) for details.
user=value
Suppress the `user' prompt and use value as the answer
instead.
service=value
Changes the systems default role. Possible settings for
value are cpu and terminal.
debugfactotum=
Causes boot(8) to start factotum with the -p option, so that
it can be debugged.
cfs=value
This gives the name of the file holding the disk partition
for the cache 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.
fs=address
auth=address
secstore=address
These specify the network address (IP or domain name) of the
file, authentication and secstore server to use when mount-
ing a network-provided root file system. When not speci-
fied, then these settings are determined via DHCP. When
secstore is not specified, then the authentication server is
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used.
PROCESSOR
*e820=type 0xstart 0xend ...
This variable is automatically generated by the boot loader
(see 9boot(8)) by doing a BIOS E820 memory scan while still
in realmode and passed to the kernel. The format is a
unordered list of decimal region type and hexadecimal 64-bit
start and end addresses of the area.
*maxmem=value
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=value
This defines what percentage of available memory is reserved
for the kernel allocation pool. The remainder is left for
user processes. The default value is 30 on CPU servers, 60
on terminals with less than 16MB of memory, and 40 on termi-
nals with memories of 16MB or more. Terminals use more ker-
nel memory because draw(3) maintains its graphic images in
kernel memory. This deprecated option is rarely necessary
in newer kernels.
*imagemaxmb=value
This limits the maximum amount of memory (in megabytes) the
graphics image memory pool can grow. The default is unlim-
ited for terminals and cpu servers.
*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=value
Setting *ncpu restricts the kernel to starting at most value
processors.
*apicdebug=
Prints a summary of the multiprocessor APIC interrupt con-
figuration.
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*nomsi=
Disables message signaled interrupts.
*notsc=
Disables the use of the per processor timestamp counter reg-
isters as high resolution clock.
*pcimaxbno=value
This puts a limit on the maximum bus number probed on a PCI
bus (default 7). For example, a value of 1 should suffice
on a 'standard' motherboard with an AGP slot. This, and
*pcimaxdno below are rarely used and only on troublesome or
suspect hardware.
*pcimaxdno=value
This puts a limit on 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.
*pcihinv=
Prints a summary of the detected PCI busses and devices.
*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=value
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=value
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
*acpi=value
The presence of this option enables ACPI and the export of
the #P/acpitbls file in arch(3) device. In multiprocessor
mode, the kernel will use the ACPI tables to configure APIC
interrupts unless a value of 0 is specified.
apm0=
This enables the ``advanced power management'' interface as
described in apm(3) and apm(8). The main feature of the
interface is the ability to watch battery life (see
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stats(8)). It is not on by default because it causes prob-
lems on some laptops.
USB
*nousbprobe=
Disable USB host controller detection.
*nousbohci=
*nousbuhci=
*nousbehci=
*nousbxhci=
Disable specific USB host controller types.
nousbrc=
Disable nusbrc(8) startup at boot time.
nousbhname=
When defined, nusbrc(8) will use the dynamically assigned
usb device address to name usb devices instead of the device
unique name.
VIDEO
monitor=value
vgasize=value
These are used not by the kernel but by termrc (see
cpurc(8)) when starting vga(8). If value is set to ask then
the user is prompted for a choice on boot.
*bootscreen=value
This is used by the kernel to attach a pre-initialized lin-
ear framebuffer that was setup by the bootloader or
firmware. The value has four space separated fields: the
resolution and bitdepth of the screen, the color channel
descriptor, the physical address of the framebuffer and a
optional aperture size.
*bootscreen=800x600x32 x8r8g8b8 0x80000000 0x001d4c00
*dpms=value
This is used to specify the screen blanking behavior of the
MGA4xx video driver. Values are standby, suspend, and off.
The first two specify differing levels of power saving; the
third turns the monitor off completely.
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).
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nvr=value
This is used by the WORM file server kernel to locate a file
holding information to configure the file system. The file
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.
EXAMPLES
A representative plan9.ini:
% cat /n/9fat:/plan9.ini
ether0=type=3C509
mouseport=ps2
modemport=1
serial0=type=generic port=0x3E8 irq=5
monitor=445x
vgasize=1600x1200x8
bootfile=/386/9pc
%
SEE ALSO
9boot(8), booting(8), boot(8)
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