DHCP Discover Requests

[slowsquirrel55]

We have 5 ESP32 devices on our network with Fortinet Firewalls and Juniper Mist Access Points, our ESP32 are struggling to get DHCP IP Addresses, in fact we see lots of broadcast messages for DHCP DISCOVER coming from the same device within milliseconds. It's like the device is not giving enough time for a DHCP server to respond. You will see the attached packet analyzer showing 1 ESP32 device sent a DHCP Discovery request at 0 base time and then again 2ms later.

What could be causing so many quick DHCP discover broadcasts from the device?

[ESP_Sprite]

Are the repeats the same? If so, they could be WiFi retransmits. WiFi packets are ACKed by the access point when received, and when the sender doesn't get that ACK, it'll think the packet is lost and will retransmit. This looks like the packet made it over OK but the ACK got lost.

[slowsquirrel55]

Yes, the repeat discover packets are identical. The weird part is that two packets were right after each other from the ESP32 within a second if you look at the packet snapshot I posted.

[ESP_Sprite]

That very much sounds like WiFi retransmits then.