samba - Jun 2015 - Is computer's password changed and how often?

Hi all,

If I well remember on MS AD computer's passwords are reset every 30 days.
Is it the case when building Samba4 AD?
If computer's passwords are changed regularly, are DC's passwords also
changed?

This question is related to SSSD configuration.
https://wiki.samba.org/index.php/Local_user_management_and_authentication/sssd
propose to use computer (DC in fact) credentials stored into some keytab
file to authenticate SSSD client's daemon.
Doing this works but if the password of the computer used to authenticate
the client is changed, I expect the keytab would not be valid anymore and
so SSSD would stop working.

Best regards,

mathias