relay "via"

[Marki]

Okay, it shows the interface name when giaddr is not set (normally at 
REQUEST/ACK stage at 1/2 lease time when no more broadcasts are used). 
Or when there is no DHCP relay at all.

Otherwise it shows the contents of giaddr.

The actual problem (for anyone who stumbles across this thread and its 
symptoms) was a bad failover configuration.
A lot of devices were doing broadcasts all the time at REQUEST/ACK stage 
even without a DISCOVER/OFFER happening first.
For some reason they were not sure about which DHCP server was the 
authoritative one I guess...

On 2023-03-23 11:19, Darren Ankney wrote:
> Hi Marki,
> 
> When it ends with via <some IP> it means the traffic was relayed by a
> relay agent.  When it ends with via <some interface> then it means the
> traffic was directly unicast from the client (or there  was no relay
> necessary because the client is attached directly to the local
> network).
> 
> Thanks,
> 
> -Darren
> 
> On Thu, Mar 23, 2023 at 5:15 AM Marki <dhcp-users at lists.roth.lu> wrote:
>> 
>> Hello,
>> 
>> I would like to understand what the part behind "via" is exactly 
>> tryingn
>> to tell me in this case.
>> 
>> Why is it once showing "vlan50" (the interface of the DHCP server
>> itself) and another time "172.17.8.1" (which is the actual DHCP relay 
>> of
>> the device in question).
>> There is no way the device is sending dhcp requests directly from
>> "vlan50", i.e. from the network directly attached to the dhcp server.
>> 
>> 2023-03-23T09:30:46.722240+01:00 dns01 dhcpd: DHCPREQUEST for
>> 172.17.8.11 from xx:yy:zz:d9:11:57 (string) via vlan50
>> 2023-03-23T09:30:46.722256+01:00 dns01 dhcpd: DHCPACK on 172.17.8.11 
>> to
>> xx:yy:zz:d9:11:57 (string) via vlan50
>> 2023-03-23T09:31:18.788021+01:00 dns01 dhcpd: DHCPREQUEST for
>> 172.17.8.11 from xx:yy:zz:d9:11:57 (string) via 172.17.8.1
>> 2023-03-23T09:31:18.788037+01:00 dns01 dhcpd: DHCPACK on 172.17.8.11 
>> to
>> xx:yy:zz:d9:11:57 (string) via 172.17.8.1
>> 
>> Thanks
>> Marki
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