
Some kennels insist, others don't. But my vet told me that even with the vaccine there are many strains of kennel cough and it won't totally immunise your dog.
My dog has had kennel cough many times, a couple quite serious, but it is treatable and he has recovered with no long term effects. Your dog can get kennel cough from the park etc so I wouldn't worry too much about him going into kennels. Just be satisfied yourself that you are happy where he is going.
CG