Re: [PATCH net-next v4 1/4] net: bonding: add broadcast_neighbor option for 802.3ad

Nikolay Aleksandrov
2025-05-14T09:46:10Z

On 5/14/25 12:36, Nikolay Aleksandrov wrote:
> On 5/14/25 12:25, Tonghao Zhang wrote:
>> Stacking technology is a type of technology used to expand ports on
>> Ethernet switches. It is widely used as a common access method in
>> large-scale Internet data center architectures. Years of practice
>> have proved that stacking technology has advantages and disadvantages
>> in high-reliability network architecture scenarios. For instance,
>> in stacking networking arch, conventional switch system upgrades
>> require multiple stacked devices to restart at the same time.
>> Therefore, it is inevitable that the business will be interrupted
>> for a while. It is for this reason that "no-stacking" in data centers
>> has become a trend. Additionally, when the stacking link connecting
>> the switches fails or is abnormal, the stack will split. Although it is
>> not common, it still happens in actual operation. The problem is that
>> after the split, it is equivalent to two switches with the same configuration
>> appearing in the network, causing network configuration conflicts and
>> ultimately interrupting the services carried by the stacking system.
>>
>> To improve network stability, "non-stacking" solutions have been increasingly
>> adopted, particularly by public cloud providers and tech companies
>> like Alibaba, Tencent, and Didi. "non-stacking" is a method of mimicing switch
>> stacking that convinces a LACP peer, bonding in this case, connected to a set of
>> "non-stacked" switches that all of its ports are connected to a single
>> switch (i.e., LACP aggregator), as if those switches were stacked. This
>> enables the LACP peer's ports to aggregate together, and requires (a)
>> special switch configuration, described in the linked article, and (b)
>> modifications to the bonding 802.3ad (LACP) mode to send all ARP / ND
>> packets across all ports of the active aggregator.
>>
>> ----------- -----------
>> | switch1 | | switch2 |
>> ----------- -----------
>> ^ ^
>> | |
>> -----------------
>> | bond4 lacp |
>> -----------------
>> | |
>> | NIC1 | NIC2
>> -----------------
>> | server |
>> -----------------
>>
>> - https://www.ruijie.com/fr-fr/support/tech-gallery/de-stack-data-center-network-architecture/
>>
>> Cc: Jay Vosburgh <jv@jvosburgh.net>
>> Cc: "David S. Miller" <davem@davemloft.net>
>> Cc: Eric Dumazet <edumazet@google.com>
>> Cc: Jakub Kicinski <kuba@kernel.org>
>> Cc: Paolo Abeni <pabeni@redhat.com>
>> Cc: Simon Horman <horms@kernel.org>
>> Cc: Jonathan Corbet <corbet@lwn.net>
>> Cc: Andrew Lunn <andrew+netdev@lunn.ch>
>> Signed-off-by: Tonghao Zhang <tonghao@bamaicloud.com>
>> Signed-off-by: Zengbing Tu <tuzengbing@didiglobal.com>
>> ---
>> Documentation/networking/bonding.rst | 6 ++++
>> drivers/net/bonding/bond_main.c | 42 ++++++++++++++++++++++++++++
>> drivers/net/bonding/bond_options.c | 35 +++++++++++++++++++++++
>> include/net/bond_options.h | 1 +
>> include/net/bonding.h | 3 ++
>> 5 files changed, 87 insertions(+)
>>
>
> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
>

Just in case anyone misses it - Jay has a few comments sent to v3 of this set:
https://lore.kernel.org/netdev/1338977.1747215491@vermin/T/#m695fa7cc6b4bf637391427bea8ad268ca7034709

It seems there will have to be another version, if you change the code please
don't add my reviewed-by tags to the changed patches because I'll have to
review them again.

Cheers,
Nik