[SOLVED] bridge network with no host access

stanna · 2018-07-04 23:19:48

I thought i had this down pat but apparently not.

I am running Arch with XFCE4 and QEMU/KVM, accessing VM's via virt-manager. I have been trying to setup a bridge network and have hit a road block. via the wiki I performed the below and easily turned it into a script that runs on boot

ip link add name br0 type bridge
ip link set br0 up
ip link set enp0s31f6 up
ip link set enp0s31f6 master br0

I configure one of the VM's running Windows 7 to use br0 and it works perfect fine and gets an IP address on the physical network BUT i dont have any internet access on my arch host. the internal network seems to be OK but i cannot access the internet.

I fear i have been starring at it for soo long now i have become blind to any of the issues and must be missing something very silly so any advice would be greatly appreciated or if further information required please let me know. Thanks in advance

Last edited by stanna (2018-08-22 01:25:03)

ejiek · 2018-07-08 17:20:55

I guess same problem here.
I have a headless Arch box sitting around with some VM behind the bridge. It was fine for the previous couple of years.

Yesterday, after the update and reboot box went offline. After connecting it to the peripherals i've found that IP addresses given by the DHCP had changed. And gateway is not accessible.

Not solved by the moment.

fukawi2 · 2018-07-09 02:04:28

stanna wrote:

ip link add name br0 type bridge
ip link set br0 up
ip link set enp0s31f6 up
ip link set enp0s31f6 master br0

Where does the IP Address of your host end up? The bridge (br0) or the physical interface (enp0s31f6)? It needs to be on the bridge interface (br0).

stanna · 2018-07-09 02:15:54

that must be it. so the stupid question is now how to i get the IP onto br0 ?

fukawi2 · 2018-07-09 02:22:34

Let us know if you get stuck: https://wiki.archlinux.org/index.php/Network_bridge

stanna · 2018-07-09 02:32:49

yes, that is where i got the initial commands from. once completed i checked "ip a" which showed the below and both enp0s31f6 and br0 have an IP Address. I can access the local networks but no internet at all.

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: enp0s31f6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br0 state UP group default qlen 1000
    link/ether 54:e1:ad:f5:d6:29 brd ff:ff:ff:ff:ff:ff
    inet 192.168.255.82/24 brd 192.168.255.255 scope global noprefixroute enp0s31f6
       valid_lft forever preferred_lft forever
    inet6 fe80::b44a:22aa:d48e:8cf5/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
3: wlp4s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether e4:70:b8:a7:c8:c1 brd ff:ff:ff:ff:ff:ff
    inet 10.0.0.129/8 brd 10.255.255.255 scope global dynamic noprefixroute wlp4s0
       valid_lft 5122sec preferred_lft 5122sec
    inet 10.0.0.120/8 brd 10.255.255.255 scope global secondary noprefixroute wlp4s0
       valid_lft forever preferred_lft forever
    inet6 fe80::7eea:4de8:4926:9fa7/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
4: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:4e:cc:dc brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
5: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:4e:cc:dc brd ff:ff:ff:ff:ff:ff
6: vnet0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
    link/ether 9e:bc:1c:24:95:76 brd ff:ff:ff:ff:ff:ff
27: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 54:e1:ad:f5:d6:29 brd ff:ff:ff:ff:ff:ff
    inet 192.168.255.65/24 brd 192.168.255.255 scope global noprefixroute br0
       valid_lft forever preferred_lft forever
    inet6 fe80::b408:7efa:4b86:b03b/64 scope link 
       valid_lft forever preferred_lft forever
    inet6 fe80::8025:cdff:fe73:95eb/64 scope link 
       valid_lft forever preferred_lft forever

fukawi2 · 2018-07-09 04:29:44

I'm guessing you have DHCP enabled on both interfaces then... Disable DHCP on the physical interface, and leave it on br0 only.

stanna · 2018-07-19 06:42:23

sadly that didnt help me with i disabled dhcp on the nic and enabled it on the bridge. not sure what else to do.

fukawi2 · 2018-07-19 06:44:33

What is the output of `ip a s` after doing that?

lo1 · 2018-07-19 18:15:43

I think I got this:

2: enp0s31f6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br0 state UP group default qlen 1000
    link/ether 54:e1:ad:f5:d6:29 brd ff:ff:ff:ff:ff:ff  <--------------------------------------------
    inet 192.168.255.82/24 brd 192.168.255.255 scope global noprefixroute enp0s31f6
       
br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 54:e1:ad:f5:d6:29 brd ff:ff:ff:ff:ff:ff   <--------------------------------------------
    inet 192.168.255.65/24 brd 192.168.255.255 scope global noprefixroute br0

br0 and enp0s31f6 have the same mac address but different ip addresses, you will need to enable promiscuous mode on each interface which is sharing the bridge in order for your network to work

ip link set enp0s31f6 up promisc on

Last edited by lo1 (2018-07-19 18:16:18)

stanna · 2018-07-24 04:34:47

sadly this had no effect.

TheSgtBilko · 2018-07-24 12:59:16

What network manager are you using? Make sure there are no "old/default" configs using enp0s31f6 in there that are set as active!

Last edited by TheSgtBilko (2018-07-24 13:06:33)

stanna · 2018-08-07 23:04:38

NetworkManager but i have not touched anything in there other than VPN/WIFI.. i have checked and there is no other configs in there other than what i have been doing.

there must be something very simple that i am missing.

stanna · 2018-08-22 01:24:46

I finally got this all working by using netctl instead of IP. i still dont fully understand how but its now working and i can run a VM on the native network which is all i wanted!

Thanks for your assistance everyone

Arch Linux

#1 2018-07-04 23:19:48

[SOLVED] bridge network with no host access

#2 2018-07-08 17:20:55

Re: [SOLVED] bridge network with no host access

#3 2018-07-09 02:04:28

Re: [SOLVED] bridge network with no host access

#4 2018-07-09 02:15:54

Re: [SOLVED] bridge network with no host access

#5 2018-07-09 02:22:34

Re: [SOLVED] bridge network with no host access

#6 2018-07-09 02:32:49

Re: [SOLVED] bridge network with no host access

#7 2018-07-09 04:29:44

Re: [SOLVED] bridge network with no host access

#8 2018-07-19 06:42:23

Re: [SOLVED] bridge network with no host access

#9 2018-07-19 06:44:33

Re: [SOLVED] bridge network with no host access

#10 2018-07-19 18:15:43

Re: [SOLVED] bridge network with no host access

#11 2018-07-24 04:34:47

Re: [SOLVED] bridge network with no host access

#12 2018-07-24 12:59:16

Re: [SOLVED] bridge network with no host access

#13 2018-08-07 23:04:38

Re: [SOLVED] bridge network with no host access

#14 2018-08-22 01:24:46

Re: [SOLVED] bridge network with no host access

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