Must I have a record of duty status (log pages) for the current day plus the last seven in my possession whenever operating a CMV?

Normally you are required to carry the previous seven consecutive days, and your record of duty status must be current to the time shown for the last change of duty status.  But, you are not required to have log pages in your possession for days where you meet a qualification for exemption such as 100 air miles or agriculture (reference Part 395.8).