When booting Plan 9 on a PC, the bootstrap programs described in
9boot(8)
first read,
via TFTP or a FAT filesystem on the boot disk,
a file containing configuration information.
This file,
/cfg/pxe/hex-digits
(TFTP; see
9boot(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.
Blank lines and
Carriage Returns
(\r)
are ignored.
#
comments 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 kernel 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.
The following sections describe how variables are used.
- ETHERNET
-
- etherX=value
-
This defines an Ethernet interface.
X,
a unique monotonically increasing number beginning at 0,
identifies an Ethernet card to be probed at system boot.
Probing stops when a card is found or there is no line for
etherX+1.
After probing 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 purposes, automatic probing can
be disabled by specifying the line
*noetherprobe=.
This automatic probing is only done by the kernel, not by
the bootstrap programs.
Thus, if you want to load a kernel over the Ethernet, you need
to specify an
ether0
line so that
9boot
can find the Ethernet card, even if the kernel would
have automatically detected it.
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[36], 8257[12], and 82573[ev] Gigabit Ethernet
PCI-Express controllers.
Completely configurable.
- rtl8169
- The Realtek 8169 Gigabit Ethernet controller.
Completely 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 configurable.
- dp83820
- National Semiconductor DP83820-based Gigabit Ethernet adapters, notably
the D-Link DGE-500T.
Completely 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 controller.
Completely configurable.
- 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.
- 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 various 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.
Completely 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 configurable, 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),
EtherFast 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 compatible 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 compatible 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.)
Completely configurable, no options need be given.
- wd8003
- Includes WD8013 and SMC Elite and Elite Ultra cards. There are varying degrees
of software configurability. 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 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 formats 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]
- wavelanpci
- PCI Ethernet adapters that use the same Wavelan
programming interface.
Currently the only tested cards are those based on the
Intersil Prism 2.5 chipset.
- DISKS, TAPES
-
(S)ATA 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 MultiMaster (Buslogic BT-*) adapters are
automatically detected and need no entries.
By default, the NCR 53c8xx driver searches for up to 32 controllers.
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 interface.
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.
- 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)
respectively.
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,
including 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.
- 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 connecting 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
respectively.
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 values 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 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 variant file systems for distributions, etc.
- bootargs=args
-
The value of this variable is passed to
boot(8)
by the kernel 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 establish the connection to the
venti server.
See
boot(8)
for more.
- cfs=partition
-
This names 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.
- 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.
- readparts=
-
Causes
boot(8)
to look for MBR and Plan 9 partition tables on all
sd(3)
disks, even before
factotum
is started, so NVRAM, for example, may be found.
On PCs,
9load
(but not
9boot)
normally does this and passes the partitions found in
#ec/sdCnpart.
- 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.
- *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 memory because
draw(3)
maintains its graphic images in kernel 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 controller.
- *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 7).
For example, a
bno
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=dno
-
Limits the maximum device number probed
on a PCI bus (default 31).
- *nopcirouting=
-
Disable pci routing during boot. May solve interrupt routing
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 interface is the ability to watch
battery life (see
stats(8)).
It is not on by default because it causes problems 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
video driver.
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[, baud]
-
Selects a serial console upon which to present the menu
as no
console
or
baud
configuration information will have been processed yet
(the
plan9.ini
contents are still to be decided...).
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.
The line
menuitem=tag
is prefixed to the selected configuration as an aid to
user-level initialization scripts.