As chestermama wrote, anal glands are a common problem and scooting and licking are usually signs that the glands are full.     
Some dogs express their glands naturally, others need to have them done manually.  There are many causes for abscess including infection.     
Max had a brief problem when he was a pup and a vet manually retrieved a stool sample.  I fed Max a few peas with dinner to give more bulk to his stool to express the glands.   
If stool is too soft or too small, it may not express the glands naturally.  My boys tend to express when they do their business on walks.     
Fiber can be helpful, but be careful adding too much fiber which can cause other problems.     
Many people learn to manually express their dog's glands, or bring them to the groomer or vet to have it done.     
				__________________  Kristin, Max and Teddy          |