I have been parsing through the logs and found a random sid doing authentications against AD. It is as follows "s-1-5-21-xxxxx-xxxxx-xxxxx-0"; It cant be found in domain or forest. I want to know if there is speciality of "-0" at the end?

1 Answer 1


It sounds like it's the domain SID. Essentially the SID of the domain itself.


domain security identifier (domain SID): The SID of the root object of a domain NC. The relative identifier (RID) portion of the domain SID is always zero. Every security principal object in a domain NC has an objectSid attribute equal to the domain SID except for the RID portion.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.