ifdown(8)
NAME
ifup - network interface management commands
NAME
ifup - bring a network interface up
ifdown - take a network interface down
SYNOPSIS
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 ...]]
DESCRIPTION
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/
file).
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.
OPTIONS
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
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.
-X EXCLUDEPATS, --exclude EXCLUDEPATS
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.
-i INTERFACESFILE, --interfaces INTERFACESFILE
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
EXAMPLES
# 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
script
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)
SEE ALSO
ifquery(8), ifreload(8), interfaces(5),
ifupdown-addons-interfaces(5)
AUTHOR
Roopa Prabhu <roopa@cumulusnetworks.com>
COPYRIGHT
Copyright 2014 Cumulus Networks, Inc. All rights reserved.
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