Re: [gentoo-user] arp question

[lee]

Adam Carter  writes:

>> Yes, I already tried that and didn't get any traffic listed.
>>
>
> In that case it sounds like linux has bridged them across from the other
> interface. Does this find anything?
> tcpdump -i enp2s0 net 192.168.1.0/24
>
> If it doesn't maybe generate some layer2 broadcast traffic on enp1s0 to see
> if you can see that traffic in the tcpdump on enp2s0. Something like;
> echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts
> ping 192.168.1.255
>
> After the test is done turn it back on with;
> echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts

Thanks!  I tried it, and nothing shows up.

> I've never bridged with linux. Bridging is usually a bad option - if you
> can I suggest you move to a routed and/or NATed solution. Clean and simple
> is best.

Most ppl seem to recommend bridging as the clean and simple solution.
How come you say that bridging is usually bad?

And how do you start a container without having a bridge on the host?
Not being able to do that is why I have the bridge in the first place.

Re: [gentoo-user] arp question

[lee]

Rich Freeman  writes:

> On Sat, Dec 26, 2015 at 9:14 AM, lee  wrote:
>>
>> They are connected to different vlans on the same switch, so they don't
>> share the same broadcast domain.  The switch shows the mac addresses of
>> the phones only in the expected vlan.
>>
>
> Out of curiosity, have you tried actually sending a broadcast on the
> VLAN to verify that it actually is implemented correctly?  If your
> switch is mixing ARP across VLANs that would explain this behavior.

Not yet --- and it won't exactly be an easy thing to do.

It's a high-quality switch.  If it couldn't keep vlans seperated, the
customers it was designed for would have them pretty much all replaced
under warranty.

> I've never messed with VLAN on linux but I'd think that you could

Me neither; so far, the switch does it.

> probably implement VLAN in software and actually save yourself a
> physical network interface as well (both interfaces could go out over
> the same wire and be handled appropriately by the switch).

Hm.  That might even be possible, in a very complicated setup.  Maybe
some day, I can do that, after lots of learning.