how to make linux reply arp request for other machines

[diel]

Hi All,

Do you know how to make linux reply arp request for other machines?



Thanks

[kakariko81280]

Depending on what you want to do, arpd might sort you out. It's part of the honeyd project to invent virtual hosts by responding to arp requests for unallocated IP addresses.

Let us know how you get on,

Chris...

[diel]

I have Linux to replay to all arp request, include hosts that are alive.
If any PC from network discover mac address in LAN, to see one mac address - mac on linux box.

PS: Sorry for my english.

vankata....

[kakariko81280]

The difficulty of this looks like it depends on how much reliability you want.

If you want to be completely sure that the only mac address visible is your Linux box then you will need to prevent the other computers talking to each other at all. I've never seen anything that can do this, but it doesn't seem unreasonable. Especially for professional equipment.

If you're not willing to spend that much or don't require an iron clad guarantee then you could use some kind of arp spoofing. I've tried this on my own, two computer, network and it seems fairly reliable. This is detectable though.

A third option would be to try something completely different. If you can tell us what you are trying to achieve with this, we might be able to point you to a better option.

Let us know how you get on,

Chris...

[diel]

Hello Chris,
My idea is to prevent computers in one ethernet segment and one VLAN to talking with each other.
In practice is impossible to split into different VLAN-s.
If my router replay to all arp request, hosts in that VLAN will be talk only wich router.

vankata...

[kakariko81280]

How does your VLAN work? I've only worked with a couple of different ways of doing this, but they always created virtual network interfaces.

If yours also creates a virtual network interface then you can separate the networks with a firewall.

Also, if your networks have different network numbers then they will not relay ARP requests to each other, they would get the mac address of the gateway. If this is the case then you already have the arp responses set up the way you want.

Let us know how you get on,

Chris...

[Bil_Bomba]

Hi

I was searching the whole web, but did not find exactly what i need. but this thread is quite close.

My problem:
server: I have a pc configured to wake on lan. not only with a magic package, but also with any unicast massage. that works quite well.

clients: in the network are several clients that want to access the services offered by the server. because i want ervery normal (not specially configured) system to be able to access the server, i dont want to change their settings.

NAS: i have a NAS (linksation) in the network running debian, which i always on.

if i configure a static arp entry on a client for the server, it work for this one client. the client sends a unicast to the server, the server goes up from suspend in 2 seconds, and everthing is fine.
but i am for some reasons not able to make static arp entries on all clients. so i would like to make my NAS replying to the arp request of the clients with the mac-address of the server.

i found arp proxy, but it answeres to arp requests with the mac adress of nas instead of the server.

any idea how to make this special configuration?
thank you