NAME

ethers − Database that maps Ethernet addresses to hostnames

DESCRIPTION

The /etc/ethers file is used in conjunction with the reverse address resolution protocol daemon (rarpd) to map Ethernet addresses to hostnames.  It contains information about the known (48-bit) Ethernet addresses of hosts on the Internet. 

For each host on an Ethernet, a single line should be present in the file with the following information: Ethernet-address        official-host-name

Items are separated by one or more spaces or tabs.  A number sign (#) indicates the beginning of a comment that extends to the end of line. 

The standard form for Ethernet addresses is: x:x:x:x:x:x

The x is a hexadecimal number between 0 and ff, representing 1 byte.  The address bytes are always in network order. 

Hostnames can contain any printable character other than a space, tab, newline, or number sign (#). 

Hostnames in the /etc/ethers file should correspond to the hostnames in the /etc/hosts file or to those provided by the name service. 

EXAMPLES

The following is a sample ethers file:

08:00:20:01:e5:1c       host1        # Comments go here
08:00:20:01:d0:4c       host2        # Comments go here
08:00:20:01:e0:1d       host3        # Comments go here
08:00:20:00:c2:4e       host4        # Comments go here

RELATED INFORMATION

Commands: rarpd(8)

Files: hosts(4), packetfilter(7)

Routines: ethers(3)