FSCONFIG(8) FSCONFIG(8)
NAME
fsconfig - configuring a file server
SYNOPSIS
service name
config device
nvram device
filsys name device
ip ipaddr
ipgw ipaddr
ipmask ipaddr
ipauth ipaddr
ipsntp ipaddr
ream name
recover name
allow
readonly
noauth
noattach
copyworm
copydev from-dev to-dev
halt
end
DESCRIPTION
When an fs(4) file server's configuration has not been set,
or by explicit request early in the server's initialization
(see fs(8)), the server enters `config mode'. The commands
described here apply only in that mode. They establish con-
figuration constants that are typically valid for the life
of the server, and therefore need be run only once. If the
non-volatile RAM on the server gets erased, it will be
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necessary to recreate the configuration.
Syntax
In these commands, ipaddr is an IP address in the form
111.103.94.19 and name is a text string without white space.
The syntax of a device is more complicated:
wn1.n2.n3
Defines a SCSI disk on target (unit) id n2, controller
(host adapter) n1, and LUN (logical unit number) n3. A
single number specifies a target, while two numbers
specify target.lun, with the missing numbers defaulting
to zero. Any one of the numbers may be replaced by
<m-n> to represent the values m through n inclusive. M
may be greater than n. For example, (w<1-4>) is the
concatenation of SCSI targets 1 through 4.
hn1.n2.n3
H is similar to w, but for IDE or ATA disks, and the
controllers must be specified in plan9.ini. Lun is
ignored. Target 0 is an IDE master and 1 is a slave.
Instead of specifying controller and target separately,
one may omit the controller and specify a target of
controller-number*2 + target-number, thus h2 is equiva-
lent to h1.0.0 (second IDE controller, master drive).
mn1.n2.n3
M is similar to h, but for SATA drives connected to
Marvell 88SX[56]0[48][01] controllers. There is no
need to specify the controllers in plan9.ini as they
are autodiscovered. Hot-swapping drives is not cur-
rently supported. Similar target naming rules apply as
for IDE controllers. However the controller-number is
multiplied by the number of drives the controller sup-
ports rather than 2. Thus m9 is equivalent to m1.1.0
(second controller, second drive), if the first con-
troller supports 8 drives.
ln1.n2.n3
rn1.n2.n3
The same as w, but leaving a single block at the begin-
ning for a label (l), or not. Only n2 is really of
interest, and refers to a side of a WORM disc. These
are only really relevant when used as device3 in the j
device (see below).
(device...)
A pseudo-device formed from the concatenation of the
devices in the list. The devices are not blank- or
comma-separated.
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[device...]
A pseudo-device formed from the block-wise interleaving
of the devices in the list. The size of the result is
the number of devices times the size of the smallest
device.
{device...}
A pseudo-device formed from the mirroring of the first
device in the list onto all the others. The size of
the result is the size of the smallest device. One
might think of this as RAID 1, and [ ] as RAID 0,
though neither includes any fancy recovery mechanisms.
Each block is written to all the devices, starting with
the rightmost in the list and working leftward. A
block is read from the first device that provides it
without error, starting with the leftmost in the list
and working rightward.
pdevice.n1.n2
A partition starting at n1% from the beginning of
device with a length n2% of the size of the device.
Parenthesize device if it contains periods.
xdevice
A pseudo-device that contains the byte-swapped contents
of device. Since the file server writes integers to
disk in its native byte order, it can be necessary to
use this device to read file systems written by proces-
sors of the other byte order.
j(device1 device2...)device3
Device1 is the SCSI juke box interface. The device2s
are the SCSI drives in the jukebox and device3 repre-
sents the demountable platters in the juke box.
fdevice
A pseudo-WORM disk: blocks on device can be written
only once and may not be read unless written.
cdevice1device2
A cached WORM. The first device is the cache, the sec-
ond the WORM.
o (Letter o) The read-only (dump) file system of the
most-recently defined cached WORM file system.
Configuration
The service command sets the textual name of the server as
known in the network databases.
The configuration information is stored in block zero on a
device whose device string is written in non-volatile RAM.
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The config and nvram commands identify the device on which
the information is recorded. The config command also erases
any previous configuration.
The filsys command configures a file system on device and
calls it name. Name is used as the specifier in attach mes-
sages to connect to that file system. (The file system main
is the one attached to if the specifier is null; see
attach(5)).
The rest of the configuration commands record IP addresses:
the file server's address (ip), the local gateway's (ipgw),
the local authentication server's (ipauth), the local subnet
mask (ipmask), and the address of a system running an SNTP
server (ipsntp). Ipauth is no longer used. If the server
has more than one network interface, a digit may be appended
to the keywords ip, ipgw and ipmask to indicate the inter-
face number; zero is the default.
One-time actions
The ream command initializes the named file system. It
overwrites any previous file system on the same device and
creates an empty root directory on the device. If name is
main, the file server, until the next reboot, will accept
wstat messages (see stat(5)) that change the owner and group
of files, to enable initializing a fresh file system from a
mkfs(8) archive.
For the recover command, the named file system must be a
cached WORM. Recover clears the associated magnetic cache
and initializes the file system, effectively resetting its
contents to the last dump.
Allow turns off all permission checking; use with caution.
Readonly disables all writing to all devices. This is use-
ful for trying dangerous experiments.
Noauth disables authentication.
Noattach prevents attachs.
Copyworm will copy a file system named main to one named
output, block by block, and loop. It knows how to read a
fake worm file system.
Copydev will copy the device from-dev to the device to-dev.
block by block, and panic.
Halt will cause the server to immediately exit and reboot.
The various configuration commands only record what to do;
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they write no data to disk. The command end exits config
mode and begins running the file server proper. The server
will then perform whatever I/O is required to establish the
configuration.
EXAMPLE
Initialize a file server kgbsun with a single file system
interleaved between SCSI targets 3 and 4.
service kgbsun
config w3
filsys main [w<3-4>]
ream main
Initialize a file server kremvax with a single disk on tar-
get 0 partitioned as a cached pseudo-WORM file system with
the cache on the third quarter of the drive and the pseudo-
WORM on the interleave of the first, second, and fourth
quarters.
service kremvax
config p(w0)50.1
filsys main cp(w0)50.25f[p(w0)0.25p(w0)25.25p(w0)75.25]
filsys dump o
ream main
A complete and complex example: initialize a file server fsb
with a single SCSI disk on target 0 for a scratch file sys-
tem, a cached WORM file system with cache disk on target 2
and an optical-disc jukebox on targets 4 (robotics) and 5
(one optical drive), and another cached WORM file system
with cache disk on target 3 and another optical-disc jukebox
on a second SCSI bus at targets 3 and 4. Both jukeboxes
contain 16 slots of optical discs. It has two Ethernet
interfaces and can reach an SNTP server on the first one.
service fsb
config w0
filsys main cw2j(w4w5)(l<0-31>)
filsys dump o
filsys hp40fx cw3j(w1.<3-4>.0)(l<0-31>)
filsys hp40fxdump o
filsys other w0
ipauth 0.0.0.0
ipsntp 10.9.0.3
ip0 10.9.0.2
ipgw0 10.9.0.3
ipmask0 255.255.0.0
ip1 10.0.0.2
ipgw1 10.0.0.1
ipmask1 255.255.0.0
ream main
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ream hp40fx
ream other
end
SOURCE
/sys/src/fs/port/config.c
SEE ALSO
Ken Thompson, ``The Plan 9 File Server''.
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