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In SoftAP DHCP Server Eventually Stops

Posted: Sat May 30, 2020 12:17 am
by ESP Lover
When connecting to an ESP32 in softAP mode from an ESP32 client, the client connects and disconnects just fine for a while. Eventually, the AP will show the following error:

dhcps: send_offer>>udp_sendto result ffffffff

The client connects but doesn't get a lease. If I try to connect from another device, like my
iPhone, it doesn't get a lease either.

I'm using AsyncTCP (me-no-dev Oct 17, 2019 version) on the server. I'm using the 1.12.2 Espressif 32 board library in PlatformIO. (Didn't work with 1.12.1 either)

Adding tcpip_adapter_dhcps_stop(TCPIP_ADAPTER_IF_AP) and tcpip_adapter_dhcps_start(TCPIP_ADAPTER_IF_AP) every minute didn't help.

Any idea why I'm unable to obtain a lease? Rebooting the AP does fix the issue so it doesn't appear to be an issue with the client.

Re: In SoftAP DHCP Server Eventually Stops

Posted: Wed Jun 03, 2020 2:55 am
by XHYZN_Marshall
I got this problem too.

I think the progress of problem happening is same as yours.

You can see my post ,but I have not solved it yet.

According to the problem tracking,the problem source is that the next function return -1:

int esp_wifi_internal_tx(wifi_interface_t wifi_if, void *buffer, uint16_t len);

DHCP uses UDP protocol for communication, and this function is the final call function of UDP,but we can't see the implementation of this function


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