Subject: Re: [PATCH 1/1] neighbour: Support broadcast ARP in neighbor PROPE state

From: Sergei Shtylyov <[email-masked]>
Date: Thu, 05 Feb 2015 15:12:24 +0300

Hello.

On 2/5/2015 10:20 AM, zhuyj wrote:

> From: eulfsam <[email-masked]>

> When the neighbor statemachine is in PROBE state, it will normally send

    State machine.

> a number of unicast ARP requests (number defined in "ucast_probes" entry
> in the proc file system, default=3) and if no reply is received, it will
> change state to FAILED.

> Enabling CONFIG_ARP_PROBE_BCAST, will make the statemachine try to send

    Likewise.

> broadcast ARP requests, and only enter FAILED state if the broadcast ARP
> requests did not receive a reply.

> Enabling CONFIG_ARP_PROBE_BCAST, makes the IPv4 ARP behaviour more
> similar to the IPv6 Neighbor Discovery protocol, and is neccessary,

    Necessary.

> if the other end only responds to broadcast ARPs.

> CC: David S. Miller <[email-masked]>
> CC: WANG Cong <[email-masked]>
> Signed-off-by: eulfsam <[email-masked]>
> Signed-off-by: zhuyj <[email-masked]>

    Need real names here.

[...]

> diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
> index bd29016..4d13edb 100644
> --- a/net/ipv4/Kconfig
> +++ b/net/ipv4/Kconfig
> @@ -259,6 +259,23 @@ config IP_PIMSM_V2
>   	  gated-5). This routing protocol is not used widely, so say N unless
>   	  you want to play with it.
>
> +config ARP_PROBE_BCAST
> +	bool "IP: ARP send broadcast ARP, if probing using unicast fails"
> +	default	y
> +	---help---
> +	  When the neighbor statemachine is in PROBE state, it will

    State machine.

> +	  normally send a number of unicast ARP requests
> +	  (number defined in "ucast_probes" entry in the proc file system, default=3)
> +	  and if no reply is received, it will change state to FAILED.
> +
> +	  Saying Y here, will make the statemachine try to send broadcast ARP

    Likewise.

> +	  requests, and only enter FAILED state if the broadcast ARP requests did not
> +	  receive a reply.
> +
> +	  Enabling this, makes the IPv4 ARP behaviour more similar to the IPv6
> +	  Neighbor Discovery protocol, and is neccessary, if the other end

    Necessary.

[...]

WBR, Sergei