Solved Double occurrence of DHCP request

Kaminar

Kaminar

Sometimes a DHCP request occurs twice:
Code: 
DHCPDISCOVER on re0 to 255.255.255.255 port 67 interval 6
DHCPDISCOVER on re0 to 255.255.255.255 port 67 interval 9
DHCPOFFER from X.X.X.X
DHCPOFFER from X.X.X.X
DHCPOFFER already seen.
I saw it on FreeBSD 11 and 12. Why does it sometimes request twice?
 
If a DHCP response isn't received within a certain time interval the request is sent again. It's assumed the first request may have gotten lost or missed, it sends out a broadcast hoping something responds.
 
That's fine, because you want to get a DHCP lease quickly :)
It's honestly nothing to worry about, your DHCP server is just a little slower to respond, but it does respond and you do get an IP address. I regularly see 3 or 4 requests on my network before a response is received.

If you look at the interval numbers you see those rising too. It sends a request, then waits, sends another request, waits a little longer, etc. DHCP will progressively wait longer and longer to send another request. Only after several requests have been done, and still no response was received, would it time-out and fail.
 
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