How do I make my password unchangeable by another administrator in my system on Ubuntu 12.04 (Precise Pangolin)?
I am an administrator in my machine and I don't want another administrator to reset my password. Is it possible?
There is no way to make your password unchangeable.
No. If you are "an administrator", it means that you can run processes with UID = 0. Running with UID 0 grants a process many capabilities.
if the O.P. is "an administrator", it means that he/she can run processes with UID = 0. Running with UID 0 grants a process many capabilities.
Can you tell the difference between them? The system cannot. UID=0 and UID=0 are the same.
You are really asking "Can one use the powers of UID=0 to protect against UID=0?".
If the O.P. is malicious, you must solve the problem in the Real World.