Port 8081 already in use, packager are either not running or not running correctly

This error occurs when running react_native, the workaround

Turn off port 8081 for the corresponding process

1. Open terminal, enter command: lsof-i:8081

2. Prompt at this point:

COMMAND PID USER FD TYPE DEVICE size/off NODE NAME

Qvodtermi 580 railgun 18u IPv4 0x68e18b35bbb37695 0t0 TCP *:sunproxyadmin (LISTEN)

3. The process PID that can occupy 8081 of this port number is: 580

4. Kill Process 580:

Kill 580

5. Run the IOS program again. OK.

Port 8081 already in use, packager are either not running or not running correctly