Bond and Bridge problem

Mimiko

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Mar 20, 2016, 2:20:04 PM3/20/16

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Hello.

Recently I want to extend my existing bond to be also a bridge to use
qemu-kvm. As seen in examples on net this is my `interfaces` file content:
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet manual
# bond-master bond0

auto eth1
iface eth1 inet manual
# bond-master bond0

auto bond0
iface bond0 inet manual
# load balancing and fault tolerance
bond-slaves eth0 eth1
# slaves none
bond-mode 802.3ad
bond-miimon 100
bond-downdelay 200
bond-updelay 200
bond-lacp-rate 4

auto br0
iface br0 inet static
address 10.10.0.159
netmask 255.255.0.0
network 10.10.0.0
broadcast 10.10.255.255
gateway 10.10.0.254
# jumbo frame support
mtu 9000
vlan-raw-device bond0
bridge_ports bond0
bridge_stp off
bridge_fd 0
bridge_maxage 0
bridge_ageing 0
bridge_maxwait 0

Last 5 options are there to try to eliminate:
br0: received packet on bond0 with own address as source address
message.
The problem is when I do `service networking restart` I get this message:
RTNETLINK answers: invalid argument
Failed to bring up br0

Also in route table dissapears default route to the gateway. Another
error is about bridge_maxage:
set max age failed: Numerical result out of range

To bring up br0 interface I run this commands:

service networking stop
ifconfig br0 down
ifconfig bond0 down
brctl delbr br0
service networking start
route add default gateway 10.10.0.254

There is a problem with bridging up br0 and I can't dig where is it. I
think it breaks at:
RTNETLINK answers: invalid argument
which is shown after
Waiting for br0 to get ready (MAXWAIT is 2 seconds).

What means that error and why I get it?

Thank you.

Igor Cicimov

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Mar 20, 2016, 6:00:06 PM3/20/16

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Did you bring eth0 and eth1 up?

Mimiko

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Mar 21, 2016, 2:40:04 AM3/21/16

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On 20.03.2016 23:57, Igor Cicimov wrote:
> Did you bring eth0 and eth1 up?

Why should I do it when script must do this all?

Igor Cicimov

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Mar 21, 2016, 3:10:04 AM3/21/16

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What script are you talking about? The interfaces are set to manual in the config thus need to be manually started.

Mimiko

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Mar 21, 2016, 3:20:04 AM3/21/16

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On 21.03.2016 09:05, Igor Cicimov wrote:
> What script are you talking about? The interfaces are set to manual in
> the config thus need to be manually started.

/etc/init.d/networking

This script does all the bring-up's of manual interfaces.

The bridge config is an extension from bond configuration, ie, eth0 and
eth1 was not changed. It were working and both interfaces a bring-up by
this script. You can see this in logs.

Igor Cicimov

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Mar 21, 2016, 3:40:03 AM3/21/16

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On 21 Mar 2016 5:13 am, "Mimiko" <vbv...@gmail.com> wrote:
>

Hold on what is vlan doing here? Remove the vlan line and try again.

Mimiko

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Mar 21, 2016, 3:40:04 AM3/21/16

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On 21.03.2016 09:31, Igor Cicimov wrote:
> Hold on what is vlan doing here? Remove the vlan line and try again.

Igor, I tried lot of options to change and comment out, including this
one, before posting here. So this option does not create a problem. It
is here for future vlan tagging enabling in production.

It must have to do with the /etc/network/if-preup.d/bridge script I
think. But why is the:
RTNETLINK answers: invalid argument

Which argument? To which command? This I can't dig out by myself.

Igor Cicimov

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Mar 21, 2016, 3:50:05 AM3/21/16

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Well then i would say you start from scratch and do all manually using ifenslave brctl first and confirm all is working before putting it in the config. Monitor syslog in the same time for errors, confirm bonding is fine in /proc/net/bonding/bond0 etc.

Mimiko

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Mar 21, 2016, 6:40:04 AM3/21/16

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On 21.03.2016 09:31, Igor Cicimov wrote:

> > The problem is when I do `service networking restart` I get this message:
> > RTNETLINK answers: invalid argument
> > Failed to bring up br0

I found the rout cause of this error:

ip link set dev br0 mtu 9000 up
RTNETLINK answers: Invalid argument
Failed to bring up br0.

And the rest options (like adding default gateway) stops processing.

Isn't incorrect to specify mtu 9000 to bridges?

How about bonds? Or, to which interfaces mtu is valable?

Mimiko

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Mar 21, 2016, 6:50:04 AM3/21/16

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On 21.03.2016 09:31, Igor Cicimov wrote:

> > The problem is when I do `service networking restart` I get this message:
> > RTNETLINK answers: invalid argument
> > Failed to bring up br0

So, to overcome MTU problem, this is my interfaces:

auto eth0
iface eth0 inet manual

bond-master bond0
up ip link set eth0 mtu 9000

auto eth1
iface eth1 inet manual

bond-master bond0
up ip link set eth1 mtu 9000

auto bond0
iface bond0 inet manual
# load balancing and fault tolerance

bond-mode 802.3ad
bond-miimon 100
bond-downdelay 200
bond-updelay 200
bond-lacp-rate 4

up ip link set bond0 mtu 9000

auto br0
iface br0 inet static
address 10.10.0.159
netmask 255.255.0.0

gateway 10.10.0.254
# vlan-raw-device bond0
bridge_ports bond0
bridge_stp off
# bridge_fd 0
# bridge_maxage 0
bridge_ageing 0
bridge_maxwait 0
up ip link set br0 mtu 9000