I have a specific question which need experience for an answer:
Why arp_ignore / arp_announce are not enable by default on linux installation (debian for example) is there a specific reason ?
Which interest to receive arp answer from wrong network interfaces ?
Thanks for your help.
Regards,
That's not Debian specific, the default is from Linux.
Check https://bugzilla.redhat.com/show_bug.cgi?id=168960 and the response from David Miller:
This behavior is consistent with the Linux IPV4 stack's adherence to the host based model of IPV4 address instead of the interface based model which is pretty much what you are asking for.
Both addressing models are described by the RFCs and are completely valid.
This should not be changed and is not a bug. If you want different behavior, the tunables are there for you to tweak, but that does not make them right for everyone as a default.
See RFC 1122, 3.3.4.2 Multihoming Requirements (Strong ES model, Weak ES model).
