Basic Infos

• This issue complies with theissue POLICY doc.
• I have read the documentation atreadthedocs and the issue is not addressed there.
• I have tested that the issue is present in current master branch (aka latest git).
• I have searched the issue tracker for a similar issue.
• If there is a stack dump, I have decoded it.
• I have filled out all fields below.

Platform

• Hardware:[other]
• Core Version:[3.0.2]
• Development Env:[Platformio]
• Operating System:[MacOS]

Settings in IDE

• Module: [Generic ESP8266 Module]
• Flash Mode:[other]
• Flash Size: [4MB]
• lwip Variant: [v1.4]
• Reset Method:[nodemcu]
• Flash Frequency:[40Mhz]
• CPU Frequency:[80Mhz]
• Upload Using:[OTA]
• Upload Speed: [115200|other] (serial upload only)

Problem Description

The hostname is not being set in the DISCOVER packet sent by the ESP8266. Some routers (Mikrotik definitely) reject the DHCP 'Option 12 - hostname' field in the REQUEST packet if it has not been sent in the DISCOVER packet previously.

This same issue has been fixed for the ESP32 in this commit:espressif/esp-lwip@13665c1

MCVE Sketch

N/A

Debug Messages

N/A

Detailed explanation and packet captures in this ESPHome issue:esphome/issues#2069 (comment)