ifup - network interface management commands


      ifup - bring a network interface up

      ifdown - take a network interface down


      ifup [-h] [-a] [-v] [-d] [--allow CLASS] [--with-depends]
             [-X   EXCLUDEPATS]   [-f]   [-n]   [-s]   [--print-dependency
             {list,dot}] [IFACE [IFACE ...]]

      ifdown [-h] [-a] [-v] [-d] [--allow CLASS] [--with-depends]
             [-X EXCLUDEPATS] [-f]  [-n]  [--print-dependency  {list,dot}]
             [IFACE [IFACE ...]]


      ifup and ifdown commands can be used to configure (or, respectively,
      deconfigure) network interfaces based on  interface  definitions  in
      the config file ifupdown2.conf (defaults to /etc/network/interfaces/

      ifquery(8) maybe used in conjunction with ifup and  ifdown  commands
      to query and validate applied/running configuration.

      ifup  always  works  on  the  current  interfaces(5) file defined in
      ifupdown2.conf (default /etc/network/interfaces).  ifdown  works  on
      the last applied interface configuration.

      ifup   on   an   already   ifup'ed   interface   will  re-apply  the
      configuration,  skipping  already  applied  configuration   wherever
      possible.  In  many  cases where config commands are idempotent, you
      will see that ifup/ifdown  will  reapply  the  config  even  if  the
      interface already has that config.

      ifup and ifdown understands interface dependency order.

      For  logical interfaces like vlans, bridges, bonds, ifup creates the
      interface and ifdown deletes the interface. Use --admin-state option
      if you only want to administratively bring the interface up/down.

      When  ifup and ifdown are used with interfaces on command line, they
      must be have a iface section in the interfaces(5) file.


      positional arguments:

      IFACE  interface list separated  by  spaces.  IFACE  list  and  '-a'
      argument are mutually exclusive.

      optional arguments:

      -h, --help
             show this help message and exit

      -a, --all
             process all interfaces marked "auto"

      -v, --verbose

      -d, --debug
             output debug info

      --allow CLASS
             ignore non-"allow-CLASS" interfaces

      -w, --with-depends
             run  with  all dependent interfaces. This option is redundant
             when -a is specified. When '-a' is specified, interfaces  are
             always executed in dependency order.

             Exclude interfaces from the list of interfaces to operate on.
             Can be specified multiple times If the excluded interface has
             dependent  interfaces, (e.g. a bridge or a bond with multiple
             enslaved interfaces) then each dependent  interface  must  be
             specified in order to be excluded.

             Uses   interfaces   file   instead   of  default  defined  in
             ifupdown2.conf (default  /etc/network/interfaces).   Also  in
             ifupdown2.conf,  users  are  not allowed to specify their own
             interfaces file unless disable_cli_interfacesfile is set to 0
             (default is 1).

      -t {native,json}, --interfaces-format {native,json}
             interfaces file format

      -f, --force
             force run all operations

      -n, --no-act
             print out what would happen, but don't do it

      -p, --print-dependency {list,dot}
             print iface dependency in list or dot format

      -m, --admin-state, --no-scripts
             don't run any addon modules/scripts. Only bring the interface
             administratively up/down

      -u, --use-current-config
             By default ifdown looks at the saved state for interfaces  to
             bring  down. This option allows ifdown to look at the current
             interfaces file. Useful when your state file is corrupted  or
             you want down to use the latest from the interfaces file

      -s, --syntax-check
             Only run the interfaces file parser


      # bringing up all interfaces
          ifup -a

      # bringing up interface list
          ifup swp1 swp2

      # bringing up interface with its dependents
          ifup br0 --with-depends

      # bringing down all interfaces
          ifdown -a

      # bringing down a single interface
          ifdown swp1

      # excluding interfaces using -X option
          ifdown -X eth0 -a

          ifup -X eth0 -a

          ifdown -X eth0 -X lo -a

      # using verbose -v option to see what is going on
          ifup -v -a

      # using debug -d option to see more of what is going on
          ifup -d -a

      # ignore errors
          ifup -a -f

          ifdown -a -f

      #  run  ifdown and ifup on all interfaces using service command/init
          service networking restart

      # run ifup on all interfaces using service command/init script
          service networking start

      # ifdown on all interfaces using service command/init script
          service networking stop

      # To run ifup/ifdown on only interfaces that changed see ifreload(8)


      ifquery(8),               ifreload(8),                interfaces(5),


   Roopa Prabhu <roopa@cumulusnetworks.com>


   Copyright 2014 Cumulus Networks, Inc.  All rights reserved.


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