Hitting enter does nothing

Author: asinn826

articles/virtual-machines/troubleshooting/serial-console-linux.md

@@ -121,7 +121,7 @@ We're aware of some issues with the serial console and the VM's operating system
 
 Issue                           |   Mitigation
 :---------------------------------|:--------------------------------------------|
-Pressing **Enter** after the connection banner does not cause a sign-in prompt to be displayed. | For more information, see [Hitting enter does nothing](https://github.com/Microsoft/azserialconsole/blob/master/Known_Issues/Hitting_enter_does_nothing.md). This issue can occur if you're running a custom VM, hardened appliance, or GRUB config that causes Linux to fail to connect to the serial port.
+Pressing **Enter** after the connection banner does not cause a sign-in prompt to be displayed. | GRUB may not be configured correctly. Run the following commands: `grub2-mkconfig -o /etc/grub2-efi.cfg` and/or `grub2-mkconfig -o /etc/grub2.cfg`. For more information, see [Hitting enter does nothing](https://github.com/Microsoft/azserialconsole/blob/master/Known_Issues/Hitting_enter_does_nothing.md). This issue can occur if you're running a custom VM, hardened appliance, or GRUB config that causes Linux to fail to connect to the serial port.
 Serial console text only takes up a portion of the screen size (often after using a text editor). | Serial consoles do not support negotiating about window size ([RFC 1073](https://www.ietf.org/rfc/rfc1073.txt)), which means that there will be no SIGWINCH signal sent to update screen size and the VM will have no knowledge of your terminal's size. Install xterm or a similar utility to provide you with the `resize` command, and then run `resize`.
 Pasting long strings doesn't work. | The serial console limits the length of strings pasted into the terminal to 2048 characters to prevent overloading the serial port bandwidth.
 Erratic keyboard input in SLES BYOS images. Keyboard input is only sporadically recognized. | This is an issue with the Plymouth package. Plymouth should not be run in Azure as you don't need a splash screen and Plymouth interferes with the platform ability to use Serial Console. Remove Plymouth with `sudo zypper remove plymouth` and then reboot. Alternatively, modify the kernel line of your GRUB config by appending `plymouth.enable=0` to the end of the line. You can do this by [editing the boot entry at boot time](https://aka.ms/serialconsolegrub#single-user-mode-in-suse-sles), or by editing the GRUB_CMDLINE_LINUX line in `/etc/default/grub`, rebuilding GRUB with `grub2-mkconfig -o /boot/grub2/grub.cfg`,  and then rebooting.