If we have to reset SDX Xenserver password and if we do not have LOM access.

we use the Xe-Serial option as mentioned below .

https://support.citrix.com/article/CTX212060/how-to-reset-root-password-of-netscaler-sdx-running-on-xenserver#:~:text=Procedure%20for%20Xenserver%207.1%3A&text=the%20locate%20keyword%20splash%20and,%2Fusr%2Fsbin%2Finit%22

1. Enter into Grub menu by rebooting the SDX device (Use the LOM console for a better experience.)
2. Select the XenServer (Serial) option and edit by giving the keyboard entry "e"
3. Change ro and replace it with rw. the locate keyword splash and replace it with init=/bin/bash
4. Boot into the single user mode (it would be F10 or ctrl-x)
5. Now you are booted into single user mode and change the root password by giving the command "passwd"
6. Reboot the system by giving the command "exec /usr/sbin/init"
7. Verify the root login on Dom0​​​​​​

However sometimes when we use xe-serial we do not see the keyword splash as mentioned in the article above .

If we do not see the word splash , we need replace ro with rw and after that add the init=/bin/bash

Press Ctrl c and see if the SDX reboots into single user mode . 

If not this time try with below options.

rw init=/sysroot/bin/sh 

Once this change has been done, press “ctrl” and “X” together to boot into single-user mode.

Within the emergency, mode type the following.

chroot /sysroot

Followed by
Passwd

Problem Cause