bridge

Ubuntu – Overwrite dockerd default settings

 in Bash / GNU/Linux  tagged bash / bridge / default-address-pools / docker / docker-compose / dockerd / GNU/Linux / network / systemctl / ubuntu by

Trying to create a new bridge on docker, we got the following error

$ docker-compose up -d;
Creating network "docker-compose_new_bridge" with driver "bridge"
ERROR: could not find an available, non-overlapping IPv4 address pool among the defaults to assign to the network

After investigating, we realized that it was due to some default limitations of docker that did not allow more virtual networks to be created. To overcome the problem, we read that we had to give access to more address space using the /etc/docker/daemon.json.

On Ubuntu that file did not exist so we created it and copied the following content to it:

{
  "default-address-pools": [
    {
      "base": "172.80.0.0/16",
      "size": 24
    },
    {
      "base": "172.90.0.0/16",
      "size": 24
    }
  ]
}

Source: https://docs.docker.com/engine/reference/commandline/dockerd/

This configuration allowed Docker to reserve the network address space 172.80.[0-255].0/24 and 172.90.[0-255].0/24, that provided the daemon a total of 512 networks each owning 256 addresses.

To apply the changes to the daemon, we restarted it:

sudo systemctl restart docker.service;

and then we applied our changes to our docker ecosystem:

docker-compose up -d;

KVM: How to configure a bridge connection in Ubuntu 11.10 2

 in Applications / Bash / GNU/Linux / HowTos / Virtualization  tagged bridge / GNU/Linux / KVM / network / visualization by

Make the file : /etc/network/interfaces  look something like this (make changes only to br0, add it if not there and to the device that you want to bridge with, we used eth1):

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet dhcp

auto eth1
iface eth1 inet dhcp

# Building a bridge to be used by the Virtual Machines
auto br0
iface br0 inet static
        address 192.168.0.10
        network 192.168.0.0
        netmask 255.255.255.0
        broadcast 192.168.0.255
        gateway 192.168.0.1
        bridge_ports eth1
        bridge_fd 9
        bridge_hello 2
        bridge_maxage 12
        bridge_stp off

Then issue: sudo /etc/init.d/networking restart
If you get:

* Running /etc/init.d/networking restart is deprecated because it may not enable again some interfaces
 * Reconfiguring network interfaces...                                                                                                                                                    RTNETLINK answers: File exists
ssh stop/waiting
ssh start/running, process 11489

Waiting for br0 to get ready (MAXWAIT is 20 seconds).
RTNETLINK answers: File exists
Failed to bring up br0.                        [ OK ]

Try bringing down the device to be bridged (eth1) like this: sudo  ifdown eth1 and then issue sudo /etc/init.d/networking restart again.
After that enable it the device again again like this: sudo  ifup eth1
If this doesn’t worked try restarting the machine, worked for us.

When properly configured ifconfig should result to something similar as this:

br0       Link encap:Ethernet  HWaddr 00:1a:64:67:d3:86  
          inet addr:192.168.0.10  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::21a:64ff:fe67:d386/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1752 errors:0 dropped:0 overruns:0 frame:0
          TX packets:18 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:136973 (136.9 KB)  TX bytes:1500 (1.5 KB)

eth0      Link encap:Ethernet  HWaddr 00:1a:64:67:d3:84  
          inet addr:10.16.20.60  Bcast:10.16.20.63  Mask:255.255.255.224
          inet6 addr: fe80::21a:64ff:fe67:d384/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:91218 errors:0 dropped:0 overruns:0 frame:0
          TX packets:51796 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:123551183 (123.5 MB)  TX bytes:4754458 (4.7 MB)
          Interrupt:16 Memory:ce000000-ce012800

eth1      Link encap:Ethernet  HWaddr 00:1a:64:67:d3:86  
          inet addr:10.16.20.33  Bcast:10.16.20.63  Mask:255.255.255.224
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:2605 errors:0 dropped:48 overruns:0 frame:0
          TX packets:38 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:321878 (321.8 KB)  TX bytes:3490 (3.4 KB)
          Interrupt:17 Memory:ca000000-ca012800

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:129 errors:0 dropped:0 overruns:0 frame:0
          TX packets:129 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:17588 (17.5 KB)  TX bytes:17588 (17.5 KB)

virbr0    Link encap:Ethernet  HWaddr b6:ae:8d:e0:06:c3  
          inet addr:192.168.122.1  Bcast:192.168.122.255  Mask:255.255.255.0
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)