How to Factory Reset the Grandstream IP Phones via SSH on Windows

 

Description

If you’re facing issues with the Grandstream phones and need to perform a factory reset via SSH, follow this step-by-step guide. This method is useful when the standard factory reset option doesn’t fully clear the device memory (nvram).


Steps

1. Enable SSH under the phone’s Web UI > Maintenance > Security Settings > Save and Apply followed by a reboot.

Figure 1: Enable the SSH option under the IP Phones’ Web Interface.

2. Download and install PuTTY on your PC. Enter the phone’s IP address under the Session tab of the application.

Figure 2: Run the Putty application from your laptop to access the SSH connection with the devices

3. Enter the IP Phone‘s admin password. Type ‘reset’ and key in the reset mode (for DP75X) in the console. You may type help for the list of supported commands.

Figure 3: Enter ‘help‘ for a list of SSH commands

4. Since Windows 10, OpenSSH is built in. Alternatively, you can connect via SSH in Windows 10/11 to reset the GRP phones remotely. Open Command Prompt, type ssh admin@{Phone_IP_Address}, and enter the admin password when prompted. Once logged in, you will see the Grandstream command shell:

Figure 4: type format 3 to reset nvram

Here are the “config” commands: 

set name variable Set a P-value (leave out the “P”) 
set ip dhcp Set WAN to DHCP mode 
set ip address Set WAN IP address 
set netmask mask Set WAN network mask 
set gw address Set WAN gateway address 
set mac address Set WAN MAC address 
get name Get a P-value (leave out the “P”) 
get ip Get WAN IP address 
get netmask Get WAN netmask 
get gw Get WAN default gateway 
unset name Unset a P-value (leave out the “P”) 
commit Write changes to flash memory 
cfg_update Apply changes 
help Show a list of available commands 
exit Leave “config” mode 
Here are the “upgrade” commands: 
set TFTP Sets upgrade mode to TFTP 
set HTTP Sets upgrade mode to HTTP 
set HTTPS Sets upgrade mode to HTTPS 
set URL server Set upgrade server URL to “server” 
commit Write any changes made by above commands to flash memory 
upgrade Perform an upgrade using selected mode 
help Show a list of available commands 
exit Leave the “upgrade” submenu