There is a way to prevent the ferrules from separating away from the bamboo, should the glue bond fail. The answer is to secure the ferrules onto the rod by driving a pin through the rod & ferrule. This pin is used in addition to the normal adhesive used.
After the ferrules have been mounted onto the rod with the glue, as normal, a very small hole is drilled through both:
I use the best adhesive on the market for ferrules. Through the years I've had a total of three rods have their ferrules separate from the bamboo & each time it was frustrating & embarrassing to me. No matter that it has been an extremely rare occurrence, from now on each & every one of my rods will be made with glued & pinned ferrules. I'm doing this to ensure that there won't be any problems in the future & so you can be sure that you won't have that problem when fishing one of my rods.
If the glue on a pinned ferrule should fail, you'll probably notice it anyway because the ferrules will start to click, or make a small noise, as you flex the rod. This doesn't mean that you should ignore that forever. You'll eventually want to get the ferrules re-glued onto the rod. The pin, though, will save you from the trouble of the ferrules coming off the bamboo.
Some rod makers will tell you silly reasons why they don't pin. I used to be one of them, but after looking & thinking over the situation I've come to realize that it adds security to the ferrules & quality overall to the rod. What decent rod maker wouldn't want that. In the end I decided that the extra time & effort of pinning all my ferrules was worth it. Sure, it wasn't a problem before this, but if it prevents just one ferrule adhesive failure on any of my rods, then it's worth it. I want you to fish my rods with confidence!!