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docs:guide-user:troubleshooting:failsafe_and_factory_reset [2023/07/29 15:58] – reorganize contents vgaeteradocs:guide-user:troubleshooting:failsafe_and_factory_reset [2024/06/23 11:45] – Tweak failsafe to remind about setting static IP for the PC richb-hanover
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 If your device becomes inaccessible, e.g. after a configuration error, then failsafe mode is there to help you out. If your device becomes inaccessible, e.g. after a configuration error, then failsafe mode is there to help you out.
 When you reboot in failsafe mode, the device starts up in a basic operating state, with a few hard coded defaults, and you can begin to fix the problem manually. When you reboot in failsafe mode, the device starts up in a basic operating state, with a few hard coded defaults, and you can begin to fix the problem manually.
 +
 +Failsafe mode can be triggered by pressing (almost any) button on the device shortly after powering it on.
 +Each router is unique, but OpenWrt watches for a WPS, Reset, or other button press.
  
 Failsafe mode **cannot**, however, fix more deeply rooted problems like faulty hardware or a broken kernel. Failsafe mode **cannot**, however, fix more deeply rooted problems like faulty hardware or a broken kernel.
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 /dev/root /rom squashfs ro,relatime 0 0 /dev/root /rom squashfs ro,relatime 0 0
 </code> </code>
 +
  
 ==== Entering failsafe mode ==== ==== Entering failsafe mode ====
-Make sure you use a wired connection, since the failsafe will disable your wireless connectivity. +Failsafe mode starts the router with the IP address 192.168.1.1, and disables 
-Sometimes you need to connect to a specific network port of your router to get connectivity. +DHCP and wireless connectivity
-**Try the LAN 1 port first.** +You will need to set your PC to a static address on the same subnet 
-For DSA devices it will enable [[https://forum.openwrt.org/t/adding-openwrt-support-for-xiaomi-ax3600/55049/9760|LAN1 only]].+(e.g., 192.168.1.10) and connect via Ethernet
 +Sometimes you need to connect to a specific network port of your router 
 +to get connectivity. 
 +**Try the LAN1 port first.** 
 +DSA devices frequently enable [[https://forum.openwrt.org/t/adding-openwrt-support-for-xiaomi-ax3600/55049/9760|LAN1 only]].
  
-On most routers, OpenWrt will blink an LED (usually "Power") during the boot process after it gets control from the initial bootloader (like u-boot)+On most routers, OpenWrt will blink an LED (usually "Power") during the boot process. 
-OpenWrt will rather early in the boot cycle check if the user wants to enter the failsafe mode instead of a normal boot. +Early in the boot cycle, OpenWrt watches for a button press (any button) 
-It listens for a button press inside a specific two second window, which is indicated with LEDs and by transmitting a UDP packet.+inside a specific two second window to indicate that it should enter failsafe mode.
  
 **To enter failsafe mode, follow one of the procedures listed below:** **To enter failsafe mode, follow one of the procedures listed below:**
  
-**Recommended for most usersWait for a flashing LED and press a button.** This is usually the easiest method once you figure out the correct moment.+**Simplest - recommended for most peoplePower on the device, wait for a flashing LED and press a button.** 
 +This can be the WPS, Reset, or other button on the device.
  
-For most users and most devices, the LEDs now (2018) provide sufficient clues as to timing to be able to avoid older recommendations to "press the XXX button as fast as you can until ..." for entering failsafe mode+The LEDs provide clues for timing the button press. 
- +Watch the LED blinking speeds immediately after powering up the router
-There are three different (power) LED blinking speeds during boot for most of the routers:+Most routers show three different (power) LED blinking speeds during boot:
  
   * A power-on sequence of lights that is specific to the device's bootloader   * A power-on sequence of lights that is specific to the device's bootloader
-  * Then a fast 5-per-second blinking rhythm during two seconds, while router waits for user to trigger the failsafe mode, typically by a button press +  * Then a fast 5-per-second blinking rhythm during two seconds, while router waits for a button press 
-  * Then either +  * Then either: 
-       * A faster, 10-per-second blink if the user pressed a button and failsafe mode was triggered +       * A faster, 10-per-second blink if failsafe mode was triggered. The device is listening on 192.168.1.1 
-       * A slower, 2.5-per-second blink continuing to the end of boot, if the failsafe was not triggered and the normal boot continues +       * A slower, 2.5-per-second blink continuing to the end of normal boot, if the failsafe was not triggered 
 +  * If you missed the timing and see the slower blink rate, just power off the device, wait a couple seconds, and try again. 
 +  
 **Alternate for expert users: Wait (with a packet sniffer) for a special broadcast packet and press a button.** The packet will be sent to destination address 192.168.1.255 port UDP 4919. **Alternate for expert users: Wait (with a packet sniffer) for a special broadcast packet and press a button.** The packet will be sent to destination address 192.168.1.255 port UDP 4919.
 The packet contains the text "//Please press button now to enter failsafe//". The packet contains the text "//Please press button now to enter failsafe//".
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 Whichever trigger you use, the device will enter failsafe mode and you can access the command line with SSH (always possible) or a serial keyboard. Whichever trigger you use, the device will enter failsafe mode and you can access the command line with SSH (always possible) or a serial keyboard.
  
-Note that modern OpenWrt always uses SSH, but early OpenWrt releases (15.05 and before) offered a telnet connection in this state but no SSH.+Note that modern OpenWrt always uses SSH for terminal connections. 
 + 
 + 
 +=================
  
 ==== Fixing your settings ==== ==== Fixing your settings ====
  • Last modified: 2024/12/07 10:49
  • by hnyman