IFTABSection: Linux Programmer's Manual (5)
Updated: 01 March 2004
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NAMEiftab - static information about the network interfaces
DESCRIPTIONThe file /etc/iftab contains descriptive information about the various network interfaces. iftab is only used by the program ifrename(8) to assign a consistent network interface name to each network interface.
/etc/iftab defines a set of mappings. Each mapping contains an interface name and a set of selectors. The selectors allow ifrename to identify each network interface on the system. 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.
MAPPINGSEach 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 NAMEThe 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 wlan0) 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.
DESCRIPTORSEach 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, other selectors are for more specialised setup.
EXAMPLE# 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
AUTHORJean Tourrilhes - firstname.lastname@example.org
SEE ALSOifrename(8), ifconfig(8), ip(8), ethtool(8), iwconfig(8).
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Time: 23:45:40 GMT, March 04, 2024