Bring down and delete bridge interface that's up

Question

How do I remove a bridge that has an IP address that was brought up manually and isn't in /etc/network/interfaces?

$ ifconfig br100                                                
    br100     Link encap:Ethernet  HWaddr 00:00:00:00:00:00                         
              inet addr:172.16.0.5  Bcast:172.16.0.255  Mask:255.255.255.0

Can't delete it:

# brctl delbr br100
bridge br100 is still up; can't delete it

Can't bring it down with ifdown:

# ifdown br100                                                  
ifdown: interface br100 not configured

score 123 · Accepted Answer · answered Feb 15 '12 at 16:15

123

Figured it out:

# ip link set br100 down
# brctl delbr br100

answered Feb 15 '12 at 16:15

Lorin Hochstein

8,285

1

To delete all bridge interfaces do sudo ip link show | grep br- | awk -F ':' '{print $2}' | tr -d ' ' | while read b; do sudo ip link set "$b" down; sudo brctl delbr "$b"; done – sebastian Nov 16 '19 at 10:12
I stumbled upon an info that "brctl" is obsolete as of centos8 (and may be missing from the repos). Use "ip" as in answer by robo – Patryk Mazurkiewicz Feb 09 '22 at 10:49
this might be useful, command to get the interface based on the ip ifconfig | grep 172.16 – Aditya Kresna Permana Jun 29 '22 at 09:14

score 35 · Answer 2 · answered Nov 19 '16 at 15:44

35

$ sudo ip link delete br0 type bridge

that's all

answered Nov 19 '16 at 15:44

robo

351

3

That is if you are on a system with iproute2 like e.g. GNU/Linux distributions. – phk Nov 19 '16 at 15:53
1

Is the "type bridge" really required here, seem it also works fine without this – Axel Heider Nov 28 '19 at 18:10

score 16 · Answer 3 · answered Feb 15 '12 at 19:45

16

To clarify this for future.

ifup and ifdown are commands from some flavours of linux. And are used to control network settings set in /etc/network/interfaces for debian based systems and /etc/sysconfig/network-scripts/ifcg* on Redhat based systems (I cannot comment on others).

Creating and removing interfaces manually is done by using ifconfig (or ip which is bit more tricky to use). Bridges can be controlled with brctl

So after removing all interfaces from a bridge with brctl delif <bridg> <if> it can be moved to "down state" with ifconfig br100 down (or ip link set br100 down) and can now be removed with brctl delbr br100

Please note that using network-manager to manage your networks might make your manually changed interfaces to reset.

answered Feb 15 '12 at 19:45

Manwe

406

There seems to be some division of labour between brctl and ip/ifconfig (as illustrated by the accepted answer above at https://unix.stackexchange.com/a/31765/262897) but also some overlap in functionality (as illustrated by e.g. https://unix.stackexchange.com/a/324535/262897). So to say "Bridges can be controlled with brctl" seems to be only part of the story. Is there a simple way to summarize the relationship between the two/three? – Christoph Mar 07 '20 at 12:38
1

brctl controls the bridge-device. E.g it binds the real network devices together to create a bridge-network device. The then created bridge-device is almost like any other network device and you control it with ip/ifconfig commands. To remove real-interfaces or the bridge, one has to first bring down the interface with ip/ifconfig. In short, brctl controls bridge creation and interface bindings. ip/ifconfig control network interface (bridge device is also network interface) state and addresses. – Manwe Mar 10 '20 at 13:48

score 14 · Answer 4 · answered Oct 14 '19 at 13:30

14

How about?

docker network prune

answered Oct 14 '19 at 13:30

Czollli

141

2

That won’t work if the bridge wasn’t configured by Docker, will it? – Stephen Kitt Oct 14 '19 at 13:45
1

It probably won't but in my case solved the issue. – Czollli Oct 18 '19 at 12:48
3

you solved my 3 days of desperation – tama Dec 04 '19 at 08:44

score 10 · Answer 5 · answered Jul 09 '17 at 00:43

10

On macOS and possibly some BSD systems:

sudo ifconfig [bridge-name] down
sudo ifconfig [bridge-name] destroy

answered Jul 09 '17 at 00:43

rien333

653

Worked for me on FreeBSD! – Michael-O Jul 15 '20 at 15:04

score 2 · Answer 6 · edited Mar 27 '17 at 10:25

2

First you need to delete all the interfaces linked to your bridge using this command

ovs-vsctl del-port br-ex INTERFACE_NAME

Then you can delete the bridge

ovs-vsctl del-br br-ex

edited Mar 27 '17 at 10:25

Romeo Ninov

17,484

answered Mar 27 '17 at 09:44

NIna

29

score 1 · Answer 7 · answered May 16 '20 at 21:58

Also run:

virsh net-list --all  
sudo virsh net-list --all   
sudo virsh net-destroy default  
sudo virsh net-undefine default  
[...]  
sudo nmcli connection show
sudo nmcli connection delete br0
[...]

before using the command in robo's answer if you're using GNU/Linux.

Bring down and delete bridge interface that's up

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