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dakoellis

Member

Registered: 2013-03-15

Posts: 22

[Solved] Netctl Bridge not working with IPv6

I'm working getting a KVM working with GPU passthrough, but I'm having an issue getting networking working how I want.  My computer has static IPv4 and IPv6 working correctly with netctl, but when I tried to create a bridge (in order for the VM to be on the same network), IPv6 stops working for some reason.  Here are my netctl files:

#Normal netctl file
Connection='ethernet'
Description='A basic static ethernet connection using iproute'
Interface=eno1

IP=static
Address='myip'
Gateway='mygw'
DNS=('mydns')

## For IPv6 static address configuration
IP6=static
Address6='myipv6'
Routes6=('myipv6route')
Gateway6='myipv6gw'

#Bridge Connection
Description="Bridge connection"
Interface=br0
Connection=bridge
BindsToInterfaces=(eno1)

IP=static
Address='myip'
Gateway='mygw'
DNS=('mydns')

## For IPv6 static address configuration
IP6=static
Address6='myipv6'
Routes6=('myipv6route')
Gateway6='myipv6gw'

SkipForwardingDelay=yes

Also, when I start the bridge interface, ip a shows both my global and link local IP addresses as tentative, and the state for br0 is unknown.  If i do an ip l set br0 up, the tentative goes away, but then I lose IPv4 as well. This does not happen if I enable it on boot; there is no tentative shown.  Here's the error that journalctl shows:

-- Reboot --
Feb 02 11:23:17 hostname systemd[1]: Starting  Bridge connection... 
Feb 02 11:23:17 hostname network[514]: Starting network profile 'bridge'...
Feb 02 11:23:18 hostname network[514]: RTNETLINK answers: Network is down
Feb 02 11:23:18 hostname systemd[1]: Started  Bridge connection.
Feb 02 11:23:21 hostname network[514]: Duplicate Address Detection is taking too long on interface 'br0'
Feb 02 11:23:21 hostname network[514]: Failed to bring the network up for profile 'bridge'
Feb 02 11:23:21 hostname systemd[1]: netctl@bridge.service: Main process exited, code=exited, status=1/FAILURE
Feb 02 11:23:21 hostname systemd[1]: netctl@bridge.service: Failed with result 'exit-code'.
lines 108-129/129 (END)

I've seen a few others have similar issues with DAD taking too long, but none of the provided solutions work.  Anyone know what I should look for to get it working?  Sorry if this is a simple one I just missed somewhere.

Thanks!

Last edited by dakoellis (2018-02-06 14:39:02)

lo1

Member

Registered: 2017-09-25

Posts: 584

Re: [Solved] Netctl Bridge not working with IPv6

ip link show en01
ip link show br0

EDIT: specifically, what happens when setting a different mac address for br0?

Last edited by lo1 (2018-02-02 21:32:23)

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dakoellis

Member

Registered: 2013-03-15

Posts: 22

Re: [Solved] Netctl Bridge not working with IPv6

So initially, the MAC addresses were the same, but when I changed br0 to a new one, I have the same issue.

2: eno1: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br0 state UP mode DEFAULT group default qlen 1000
    link/ether 48:0f:cf:41:63:fe brd ff:ff:ff:ff:ff:ff
3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
    link/ether 4e:b1:ab:66:c1:9d brd ff:ff:ff:ff:ff:ff

Also not sure if I mentioned this yet, but the br0 device has the correct IPv6 Address shown by ip addr

Last edited by dakoellis (2018-02-03 01:48:12)

lo1

Member

Registered: 2017-09-25

Posts: 584

Re: [Solved] Netctl Bridge not working with IPv6

Nope, I don't know what's happening. I'd suggest to stop using netctl but as you said:

If i do an ip l set br0 up, the tentative goes away, but then I lose IPv4 as well.

so not sure what good could it be. What about your provider? (which is, the service you're connecting to)

I'm having an issue getting networking working how I want

What about "getting networking how i want"? What are you trying to accomplish?

Last edited by lo1 (2018-02-03 14:06:37)

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dakoellis

Member

Registered: 2013-03-15

Posts: 22

Re: [Solved] Netctl Bridge not working with IPv6

Provider is a university with public ips. My goal is to get ipv6 working inside a VM, but with the ability to pass traffic between the host and the VM. As of now, I can do one or the other based on which network device I use in virt-manager.

What would you suggest instead? Just using ip to set it up? I'll give it a shot anyway

Last edited by dakoellis (2018-02-05 04:35:16)

dakoellis

Member

Registered: 2013-03-15

Posts: 22

Re: [Solved] Netctl Bridge not working with IPv6

So it's working now... I removed the addresses on eno1 with ip (including link-local) and added them to br0 afterward, and that didn't work.  Then I disabled netctl, rebooted, created a bridge with ip, changed both devices to a random MAC, and gave br0 the addresses, and that worked.  Now, when I use netctl, IPv6 is working fine as well.  Not sure what exactly was the difference between the first time and now, besides redoing br0 manually.