Re: [Bug 194749] New: kernel bonding does not work in a network nameservice in versions above 3.10.0-229.20.1

2017-03-03 Thread Dan Geist


- On Mar 3, 2017, at 11:03 AM, Jiri Pirko j...@resnulli.us wrote:

> Fri, Mar 03, 2017 at 04:19:13PM CET, nicolas.dich...@6wind.com wrote:
>>Le 02/03/2017 à 21:39, Dan Geist a écrit :
>>> - On Mar 2, 2017, at 3:11 PM, Cong Wang xiyou.wangc...@gmail.com wrote
>>> 
>>>> On Thu, Mar 2, 2017 at 10:32 AM, Stephen Hemminger
>>>> <step...@networkplumber.org> wrote:
>>>>>
>>>>>
>>>>> Begin forwarded message:
>>>>>
>>>>> Date: Wed, 01 Mar 2017 21:08:01 +
>>>>> From: bugzilla-dae...@bugzilla.kernel.org
>>>>> To: step...@networkplumber.org
>>>>> Subject: [Bug 194749] New: kernel bonding does not work in a network 
>>>>> nameservice
>>>>> in versions above 3.10.0-229.20.1
>>>>
>>>>>
>>>>> https://bugzilla.kernel.org/show_bug.cgi?id=194749
>>>>>
>>>>> Bug ID: 194749
>>>>>Summary: kernel bonding does not work in a network nameservice
>>>>> in versions above 3.10.0-229.20.1
>>>>>Product: Networking
>>>>>Version: 2.5
>>>>> Kernel Version: > 3.10.0-229.20.1
>>>>>   Hardware: x86-64
>>>>> OS: Linux
>>>>>   Tree: Mainline
>>>>> Status: NEW
>>>>>   Severity: blocking
>>>>>   Priority: P1
>>>>>  Component: Other
>>>>>   Assignee: step...@networkplumber.org
>>>>>   Reporter: d...@polter.net
>>>>> Regression: No
>>>>>
>>>>> bond interface is being used in active/standby mode with two physical NICs
>>>>> inside a network nameservice to provide switchpath redundancy.
>>>>>
>>>>> netns is instantiated post-boot with the following:
>>>>>
>>>>> ip netns add vntp
>>>>> ip link set p4p1 netns vntp
>>>>> ip link set p4p2 netns vntp
>>>>> ip link set bond0 netns vntp
>>>>> ip netns exec vntp ip link set lo up
>>>>> ip netns exec vntp ip link set p4p1 up
>>>>> ip netns exec vntp ip link set p4p2 up
>>>>> ip netns exec vntp ip link set bond0 up
>>>>> ip netns exec vntp ifenslave bond0 p4p1 p4p2
>>>>
>>>> This is due to the following commit:
>>>>
>>>> commit f9399814927ad9bb995a6e109c2a5f9d8a848209
>>>> Author: Weilong Chen <chenweil...@huawei.com>
>>>> Date:   Wed Jan 22 17:16:30 2014 +0800
>>>>
>>>>bonding: Don't allow bond devices to change network namespaces.
>>>>
>>>>Like bridge, bonding as netdevice doesn't cross netns boundaries.
>>>>
>>>>Bonding ports and bonding itself live in same netns.
>>>>
>>>>Signed-off-by: Weilong Chen <chenweil...@huawei.com>
>>>>Signed-off-by: David S. Miller <da...@davemloft.net>
>>>>
>>>>
>>>> NETIF_F_NETNS_LOCAL was introduced for loopback device which
>>>> is created for each netns, it is not clear why we need to add it to bond
>>>> and bridge...
>>> 
>>> Thank you for tracking this down. Without digging through the code to 
>>> figure it
>>> out, does this imply that the existence of a bond interface is not possible 
>>> AT
>>> ALL within a netns or simply that it may not be "migrated" between the 
>>> global
>>> scope and a netns?
>>It means that the migration is not possible. I think the only reason to have
>>this flag on bonding and bridge is the lack of test and fix. There is probably
>>some work to be done to have this feature. But are there real use cases of
>>x-netns bonding or x-netns bridge?
> 
> If that use case exists I believe it is an abuse. Soft devices that are
> by definition in upper-lower relationships with other devices should not
> move to other namespaces. Prevents all kinds of issues. If you need a
> soft device like bridge of bond within a namespace, just create it there.

I think the implementation is good as it stands and i don't have a use case to 
the contrary. I simply misunderstood the implications of creating the bond 
interface in the global space and had been utilizing the unnecessarily 
permissive behavior of the older kernels. Once I stopped doing that and 
migrated the instance creation to within the netns, my desired behavior and 
functionality were restored. I also commented the bug report on vger as such.

Thanks for the clarification and consideration.
Dan 

-- 
Dan Geist dan(@)polter.net



Re: [Bug 194749] New: kernel bonding does not work in a network nameservice in versions above 3.10.0-229.20.1

2017-03-02 Thread Dan Geist
- On Mar 2, 2017, at 3:11 PM, Cong Wang xiyou.wangc...@gmail.com wrote

> On Thu, Mar 2, 2017 at 10:32 AM, Stephen Hemminger
> <step...@networkplumber.org> wrote:
>>
>>
>> Begin forwarded message:
>>
>> Date: Wed, 01 Mar 2017 21:08:01 +
>> From: bugzilla-dae...@bugzilla.kernel.org
>> To: step...@networkplumber.org
>> Subject: [Bug 194749] New: kernel bonding does not work in a network 
>> nameservice
>> in versions above 3.10.0-229.20.1
>>
>>
>> https://bugzilla.kernel.org/show_bug.cgi?id=194749
>>
>> Bug ID: 194749
>>Summary: kernel bonding does not work in a network nameservice
>> in versions above 3.10.0-229.20.1
>>Product: Networking
>>Version: 2.5
>> Kernel Version: > 3.10.0-229.20.1
>>   Hardware: x86-64
>> OS: Linux
>>   Tree: Mainline
>> Status: NEW
>>   Severity: blocking
>>   Priority: P1
>>  Component: Other
>>   Assignee: step...@networkplumber.org
>>   Reporter: d...@polter.net
>> Regression: No
>>
>> bond interface is being used in active/standby mode with two physical NICs
>> inside a network nameservice to provide switchpath redundancy.
>>
>> netns is instantiated post-boot with the following:
>>
>> ip netns add vntp
>> ip link set p4p1 netns vntp
>> ip link set p4p2 netns vntp
>> ip link set bond0 netns vntp
>> ip netns exec vntp ip link set lo up
>> ip netns exec vntp ip link set p4p1 up
>> ip netns exec vntp ip link set p4p2 up
>> ip netns exec vntp ip link set bond0 up
>> ip netns exec vntp ifenslave bond0 p4p1 p4p2
> 
> This is due to the following commit:
> 
> commit f9399814927ad9bb995a6e109c2a5f9d8a848209
> Author: Weilong Chen <chenweil...@huawei.com>
> Date:   Wed Jan 22 17:16:30 2014 +0800
> 
>bonding: Don't allow bond devices to change network namespaces.
> 
>Like bridge, bonding as netdevice doesn't cross netns boundaries.
> 
>Bonding ports and bonding itself live in same netns.
> 
>Signed-off-by: Weilong Chen <chenweil...@huawei.com>
>Signed-off-by: David S. Miller <da...@davemloft.net>
> 
> 
> NETIF_F_NETNS_LOCAL was introduced for loopback device which
> is created for each netns, it is not clear why we need to add it to bond
> and bridge...

Thank you for tracking this down. Without digging through the code to figure it 
out, does this imply that the existence of a bond interface is not possible AT 
ALL within a netns or simply that it may not be "migrated" between the global 
scope and a netns?

In order for the CentOS network stack to init the interfaces, I've been 
creating them with the standard system configuration files:

[root@01 network-scripts]# cat ifcfg-p4p1 
TYPE=Ethernet
BOOTPROTO=none
DEVICE=p4p1
ONBOOT=yes
MASTER=bond0
SLAVE=yes
UUID=4e6c40ee-cc05-4f88-a851-b3185dbdcd0f
NAME=p4p1

[root@01 network-scripts]# cat ifcfg-p4p2
TYPE=Ethernet
BOOTPROTO=none
DEVICE=p4p2
ONBOOT=yes
MASTER=bond0
SLAVE=yes
UUID=15135328-12b8-4fe3-8940-db02b77b94d9
NAME=p4p2

[root@01 network-scripts]# cat ifcfg-bond0 
DEVICE=bond0
TYPE=Bond
BONDING_MASTER=yes
NAME=bond0
UUID=97674993-0e50-4a00-a210-c66d75481a84
ONBOOT=yes
BONDING_OPTS="updelay=0 resend_igmp=1 use_carrier=1 miimon=100 downdelay=0 
xmit_hash_policy=0 primary_reselect=0 fail_over_mac=0 arp_validate=0 
mode=active-backup lacp_rate=0 arp_interval=0 ad_select=0"
IPV6INIT=no


Perhaps by not instantiating the bond interface until after the netns is 
created, this situation can be avoided?

Thanks.
Dan

-- 
Dan Geist dan(@)polter.net