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iftab - статическая информация о сетевых интерфейсах

ОПИСАНИЕ

Файл /etc/iftab содержит описывающую информацию о различных сетевых интерфейсах.
iftab используется только программой ifrename(8) чтобы назначить согласованное имя
сетевого интерфейса для каждого сетевого интерфейса.

/etc/iftab определяет набор отображения. Каждое сопоставление содержит имя
интерфейса и набор селекторов. Селекторы позволяют ifrename ивыполнять
идентифицикацию каждого сетевого интерфейса в системе. Если сеть интерфейса
соответствует всем дескрипторам отображения, ifrename попытается изменить имя
интерфейса на имя интерфейса заданное отображением.

MAPPINGS

Each mapping is described on a separate line, it starts with an interface name,
and contains a set of descriptors, separated by space or tabs.

The relationship between descriptors of a mapping is a logical and. A mapping
matches a network interface only is all the descriptors match. If a network
interface doesn't support a specific descriptor, it won't match any mappings using
this descriptor.

If you want to use alternate descriptors for an interface name (logical or),
specify two different mappings with the same interface name (one on each line).
Ifrename always use the first matching mapping starting from the end of iftab,
therefore more restrictive mapping should be specified last.

INTERFACE NAME

The first part of each mapping is an interface name. If a network interface
matches all descriptors of a mapping, ifrename attempt to change the name of the
interface to the interface name given by the mapping.

The interface name of a mapping is either a plain interface name (such as eth2 or
wlan1) or a interface name pattern containing a single wildcard (such as eth* or
wlan*). In case of wildcard, the kernel replace the '*' with the lowest available
integer making this interface name unique. Note that wildcard is only supported
for kernel 2.6.1 and 2.4.30 and later.

It is discouraged to try to map interfaces to default interfaces names such as
eth0, wlan0 or ppp0. The kernel use those as the default name for any new
interface, therefore most likely an interface will already use this name and
prevent ifrename to use it. Even if you use takeover, the interface may already be
up in some cases. Not using those name will allow you to immediately spot
unconfigured or new interfaces.
Good names are either totally unique and meaningfull, such as mydsl or privatehub,
or use larger integer, such as eth5 or wlan5. The second type is usually easier
to integrate in various network utilities.

DESCRIPTORS

Each descriptor is composed of a descriptor name and descriptor value. Descriptors
specify a static attribute of a network interface, the goal is to uniquely
identify each piece of hardware.

Most users will only use the mac selector despite its potential problems, other
selectors are for more specialised setup. Most selectors accept a '*' in the
selector value for wilcard matching, and most selectors are case insensitive.
arp arp type
Matches the ARP Type (also called Link Type) of the interface with the
specified ARP type as a number. The ARP Type of the interface can be shown
using ifconfig(8) or ip(8), the link/ether type correspond to 1 and the
link/ieee802.11 type correspond to 801.
This selector is useful when a driver create multiple network interfaces
for a single network card.

driver driver name
Matches the Driver Name of the interface with the specified driver name.
The Driver Name of the interface can be shown using ethtool -i(8).

businfo bus information
Matches the Bus Information of the interface with the specified bus
information. The Bus Information of the interface can be shown using
ethtool -i(8).

firmware firmware revision
Matches the Firmware Revision of the interface with the firmware revision
information. The Firmware Revision of the interface can be shown using
ethtool -i(8).

baseaddress base address
Matches the Base Address of the interface with the specified base address.
The Base Address of the interface can be shown using ifconfig(8).
Because most cards use dynamic allocation of the Base Address, this
selector is only useful for ISA and EISA cards.

irq irq line
Matches the IRQ Line (interrupt) of the interface with the specified IRQ
line. The IRQ Line of the interface can be shown using ifconfig(8).
Because there are IRQ Lines may be shared, this selector is usually not
sufficient to uniquely identify an interface.

iwproto wireless protocol
Matches the Wireless Protocol of the interface with the specified wireless
protocol. The Wireless Protocol of the interface can be shown using
iwconfig(8) or iwgetid(8).
This selector is only supported on wireless interfaces and is not
sufficient to uniquely identify an interface.

pcmciaslot pcmcia slot
Matches the Pcmcia Socket number of the interface with the specified slot
number. Pcmcia Socket number of the interface can be shown using cardctl
ident(8).
This selector is usually only supported on 16 bits cards, for 32 bits cards
it is advised to use the selector businfo.

prevname previous interface name
Matches the name of the interface prior to renaming with the specified
oldname.
This selector should be avoided as the previous interface name may vary
depending on various condition. A system/kernel/driver update may change
the original name. Then, ifrename or another tool may rename it prior to
the execution of this selector.

SYSFS{filename} value
to match attributes in subdirectories.

Some sysfs attributes are symlinks, pointing to another directory in sysfs. If the
attribute filename is a symlink the sysfs attribute resolves to the name of the
directory pointed by the symlink using readlink(1). The location is a directory
in the sysfs tree is also important. If the attribute filename ends with /.., the
sysfs attribute resolves to the real name of the parent directory using pwd(1).

The sysfs filesystem is only supported with 2.6.X kernel and need to be mounted
(usually in /sys). sysfs selectors are not as efficient as other selectors,
therefore they should be avoided for maximum performance.

These are common sysfs attributes and their corresponding ifrename descriptors.

SYSFS{address} value
Same as the mac descriptor.

SYSFS{type} value
Same as the arp descriptor.

SYSFS{device} value
Valid only up to kernel 2.6.20. Same as the businfo descriptor.

SYSFS{..} value
Valid only from kernel 2.6.21. Same as the businfo descriptor.

SYSFS{device/driver} value
Valid only up to kernel 2.6.20. Same as the driver descriptor.

SYSFS{../driver} value
Valid only from kernel 2.6.21. Same as the driver descriptor.

SYSFS{device/irq} value
Valid only up to kernel 2.6.20. Same as the irq descriptor.

SYSFS{../irq} value
Valid only from kernel 2.6.21. Same as the irq descriptor.

EXAMPLES

# This is a comment
eth2 mac 08:00:09:DE:82:0E
eth3 driver wavelan interrupt 15 baseaddress 0x390
eth4 driver pcnet32 businfo 0000:02:05.0
air* mac 00:07:0E:* arp 1
myvpn SYSFS{address} 00:10:83:* SYSFS{type} 1
bcm* SYSFS{device} 0000:03:00.0 SYSFS{device/driver} bcm43xx
bcm* SYSFS{..} 0000:03:00.0 SYSFS{../driver} bcm43xx

AUTHOR

Jean Tourrilhes - jt@hpl.hp.com

FILES

/etc/iftab

SEE ALSO

ifrename(8), ifconfig(8), ip(8), ethtool(8), iwconfig(8).