FSCONFIG(8) FSCONFIG(8)
NAME
fsconfig - configuring a file server
SYNOPSIS
service name
config device
nvram device
filsys name device
ip ipaddr
ipflag flags
ipgw ipaddr
ipmask ipaddr
ipsntp ipaddr
ream name
recover name
readonly
noattach
halt
end
DESCRIPTION
When a 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 nec-
essary 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
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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
Defines an ATA disk similar to w. 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
Define a Marvell 88SX[56]0[48][01] disk similer to w.
Hot-swapping drives is supported. Similar target nam-
ing rules apply as for IDE controllers. However the
controller-number is multiplied by the number of drives
the controller supports rather than 2. Thus m9 is
equivalent to m1.1.0 (second controller, second drive),
if the first controller supports 8 drives.
an1.n2.n3
Define an AHCI disk similer to m.
en1.n2
Specify an AoE target. n1 is the shelf while n2 is the
slot. Luns are not used for AoE targets.
(device...)
A pseudo-device formed from the concatenation of the
devices in the list. The devices are not blank- or
comma-separated.
[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 without recovery, and [ ]
as RAID 0. 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
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provides it without error, starting with the leftmost
in the list and working rightward.
pdevice.n1.n2
Partition device. If n1 is less than 101, then A par-
tition starting at n1% from the beginning of device
with a length n2% of the size of the device. Other-
wise, n1 is the absolute starting block number and n2
is the absolute ending block number. Blocks are
RBUFSIZE bytes. This is a file server compile-time
constant, usually 8192 bytes. It is recommended that
AoE targets not be partitioned by percentage as a
replaced drive might not have exactly the same number
of blocks. Parenthesize device if it contains periods.
pdevice"partname"
Partition device with named partition. Both fdisk and
prep(8) partitions are supported. Prep partitons have
their given name. Fdisk partitions are named as in
9load(8). Thus the first dos partition is named "dos,"
the first Plan 9 partition is named "plan9" and the nth
Plan 9 partition is named "plan9.n."
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.
fdevice
A pseudo-WORM disk: blocks on device can be written
only once and may not be read unless written. A
pseudo-WORM is intended for debugging. It can be a
source of consternation if the size of the underlying
device changes by a few blocks as the blocks-written
bitmap is kept at an offset from the end of the device.
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.
The config and nvram commands identify the device on which
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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 (ipgw),
the local netmask (ipmask), the local interface flags
(ipflag), and the address of a system running an SNTP server
(ipsntp). ip, ipgw and ipmask to indicate the interface
number; zero is the default. Ipflag may allow running
cec(8) (cec), AoE (aoe), and AoE jumbo frames (aoejumbo).
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.
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.
Readonly disables all writing to all devices. This is use-
ful for trying dangerous experiments.
Noattach prevents attaches.
Halt will cause the server to immediately exit and reboot.
The various configuration commands only record what to do;
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-
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WORM on the interleave of the first, second, and fourth
quarters. The performance of this example will be poor due
to seek conflict between the cache and pseudo-WORM.
service kremvax
config p(w0)50.1
filsys main cp(w0)50.25[p(w0)0.25p(w0)25.25p(w0)75.25]
filsys dump o
ream main
A complete and complex example: initialize a file server ila
with a single AoE target on e565.2 for a scratch file sys-
tem, a cached pseudo-WORM file system with cache on 25GB of
target e565.0 and worm mirrored on targets e565.1 and
e565.1. It has two ethernet interfaces. Interface 0 is
used for client connections and a connection to shelf 545.
Interface 1 is a point-to-point link to shelf 565 and allows
jumbo frames. Cec(8) is allowed on both interfaces. The
SMTP server is global to the system. SMTP uses routing to
determine how to contact the server.
config p(a5)95.5
service ila
filsys main cp(e565.0)0.3276800{e565.1e545.1}
filsys dump o
filsys other e565.2
ipsmtp 128.192.1.9
ip0 205.185.197.7
ipgw0 206.186.197.254
ipmask0 255.255.255.0
ipflag0 cec aoe
ip1 205.185.197.106
ipgw1 205.185.197.254
ipmask1 255.255.255.0
ipflag1 cec aoe aoejumbo
end
The plan9.ini(8) for this server is as follows
console=0
bootfile=sdC0!9fat!9ilafs
ether0=type=m10g
ether1=type=m10g
nvr=hd!0!9fat!fs.nvr
*nodumpstack=0
SOURCE
/sys/src/fs/port/config.c
SEE ALSO
fs(8), mkfsconf(8)
Ken Thompson, ``The Plan 9 File Server''.
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Sean Quinlan, ``A Cached WORM File System'', Software -
Practice and Experience, December, 1991
Erik Quanstrom ``The Diskless Fileserver'', Procedings of
IWP92, December, 2007.
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