man.rst/interfaces.5.rst

   1 ==========
   2 interfaces
   3 ==========
   4
   5 --------------------------------------------
   6 network interface configuration for ifupdown
   7 --------------------------------------------
   8
   9 :Author: roopa@cumulusnetworks.com
  10 :Date:   2014-02-05
  11 :Copyright: Copyright 2014 Cumulus Networks, Inc.  All rights reserved.
  12 :Version: 0.1
  13 :Manual section: 5
  14
  15 DESCRIPTION
  16 ===========
  17     **/etc/network/interfaces** contains network interface configuration
  18     information for the **ifup(8)**, **ifdown(8)** and **ifquery(8)** commands.
  19
  20     This is where you configure how your system is connected to the network.
  21
  22     Lines starting with # are ignored. Note that end-of-line comments are
  23     NOT supported, comments must be on a line of their own.
  24
  25     A line may be extended across multiple lines by making the last character
  26     a backslash.
  27
  28     The file consists of zero or more "iface", "auto",  "allow-"
  29     and "source" stanzas. Here is an example::
  30
  31         auto lo eth0
  32         allow-hotplug eth1
  33
  34         iface lo inet loopback
  35
  36         source /etc/network/interfaces.d/machine-dependent
  37
  38         iface eth0-home inet static
  39             address 192.168.1.1/24
  40             up flush-mail
  41
  42         iface eth0-work inet dhcp
  43
  44         iface eth1 inet dhcp
  45
  46     Lines beginning with the word "auto" are used to identify the physical
  47     interfaces to be brought up when ifup is run with the -a option.
  48     (This option is used by the system boot scripts.) Physical interface names
  49     should follow the word "auto" on the same line.  There can be  multiple
  50     "auto"  stanzas.
  51
  52     Lines beginning with "allow-" are  used  to  identify  interfaces  that
  53     should  be  brought  up automatically by various subsytems. This may be
  54     done using a command such as "ifup --allow=hotplug  eth0  eth1",  which
  55     will  only  bring up eth0 or eth1 if it is listed in an "allow-hotplug"
  56     line. Note that "allow-auto" and "auto" are synonyms.
  57
  58     Lines beginning with "source" are used to include  stanzas  from  other
  59     files, so configuration can be split into many files. The word "source"
  60     is followed by the path of file to be sourced. Shell wildcards  can  be
  61     used.  (See wordexp(3) for details.). Currently only supports absolute
  62     path names.
  63
  64     ifup is normally given a physical interface name as its first non-option
  65     argument.
  66
  67     The interface name is followed by the name of the address family that the
  68     interface uses. This will be "inet" for TCP/IP networking and inet6 for
  69     ipv6. Following that is the name of the method used to configure the
  70     interface.
  71
  72     ifupdown2 supports iface stanzas without a family or a method. This enables
  73     using the same stanza for inet and inet6 family addresses.
  74
  75     Interface options can be given on subsequent lines in the iface stanza.
  76     These options come from addon modules. see interfaces-addons(5) for
  77     these options.
  78
  79     ifupdown2 supports python-mako style templates in the interfaces file.
  80     See examples section for details.
  81
  82 METHODS
  83 =======
  84     Both inet and inet6 address family interfaces can use the following
  85     methods (However they are not required):
  86
  87     The loopback Method
  88            This method may be used to define the loopback interface.
  89
  90     The static Method
  91            This method may be used to define ethernet interfaces with
  92            statically allocated addresses.
  93
  94     The dhcp Method
  95            This method may be used to obtain an address via DHCP.
  96
  97 BUILTIN INTERFACES
  98 ==================
  99     iface sections for some interfaces like physical interfaces or vlan
 100     interfaces in dot notation (like eth1.100) are understood by ifupdown2.
 101     These kind of interfaces do not need an entry in the interfaces file.
 102     However, if these interfaces need extra configuration like addresses, they
 103     will need to be specified.
 104
 105 EXAMPLES
 106 ========
 107     Sample /etc/network/interfaces file::
 108
 109         auto lo
 110         iface lo
 111             address 192.168.2.0/24
 112             address 2001:dee:eeee:1::4/128
 113
 114         auto eth0
 115         iface eth0 inet dhcp
 116
 117         auto eth1
 118         iface eth1 inet manual
 119             address 192.168.2.0/24
 120             address 2001:dee:eeee:1::4/128
 121
 122         # source files from a directory /etc/network/interfaces.d
 123         source /etc/network/interfaces.d/*
 124
 125         # Using mako style templates
 126         % for v in [11,12]:
 127             auto vlan${v}
 128             iface vlan${v} inet static
 129                 address 10.20.${v}.3/24
 130         % endfor
 131
 132     For additional syntax and examples see **ifupdownaddons-interfaces(5)**
 133
 134 FILES
 135 =====
 136     /etc/network/interfaces
 137
 138 SEE ALSO
 139 ========
 140     ifupdownaddons-interfaces(5),
 141     ifup(8),
 142     ifquery(8),
 143     ifreload(8)