Ubuntu 16.04重启后WiFi不显示，Network Manager修复无效求助

Hey Sahil, let's work through this WiFi issue together—reboots sometimes leave network adapters in a weird state, or there might be a driver/configuration glitch at play. Let's start with the most straightforward checks first:

1. Verify Physical/Soft WiFi Toggle #

First, rule out the simplest causes:

• Check if your laptop has a physical WiFi switch (usually on the side or front) and make sure it's flipped to the "on" position.
• Try the Fn + WiFi key combo (look for a WiFi icon on your function keys) to toggle WiFi on/off a couple times.
• Use the rfkill tool to check for software blocks:

  rfkill list
  

  If you see Soft blocked: yes next to your WiFi adapter, unblock it with:

  sudo rfkill unblock wifi
  

2. Check Network Manager's WiFi Radio State #

Sometimes Network Manager might disable the WiFi radio automatically:

• Check the current state:

  nmcli radio wifi
  

• If it returns off, turn it back on:

  nmcli radio wifi on
  

• You can also verify this via the graphical network menu—look for a "Enable WiFi" toggle and make sure it's checked.

3. Inspect WiFi Driver Loading #

From your lshw -C network output, note the product and vendor lines (e.g., "Intel Corporation Wi-Fi 6 AX200" or "Broadcom Inc. and subsidiaries BCM4352 802.11ac Wireless Network Adapter"). Then:

• List loaded drivers matching your adapter:

  # For Intel adapters, try:
  lsmod | grep iwlwifi
  # For Broadcom adapters, try:
  lsmod | grep brcmfmac
  

• If the driver isn't listed, reload it (replace <driver-name> with your actual driver):

  sudo modprobe -r <driver-name>
  sudo modprobe <driver-name>
  

4. Check for Kernel/Driver Mismatches #

If you recently updated your system kernel, it's possible the WiFi driver isn't compatible with the new kernel:

• Reboot your laptop and select an older kernel from the GRUB menu (under "Advanced options for Ubuntu" or similar).
• If WiFi works with the old kernel, you may need to wait for a driver update or install a DKMS version of the driver that supports the new kernel.

5. Confirm Hardware Recognition & BIOS Settings #

If none of the above works, check if the system is even detecting the WiFi adapter:

• Run this command to list network devices:

  ip link show
  

  Look for an interface named wlan0 or wlp2s0—if it's missing, reboot into your BIOS/UEFI and ensure the WiFi adapter is enabled (look for options like "Wireless LAN" or "WiFi Controller").

Let me know which step works for you, or share more details from your lshw -C network output if you hit a wall!

内容的提问来源于stack exchange，提问作者Sahil Gupta