Lets face it, none of us like the vacuum cleaner, but if your dog goes nuts every time you get the vacuum cleaner out, this can be pretty stressful for both you and for your dog. The noise alone is enough to trigger a reaction in some dogs, but combined with the movement, this can send some dogs into "attack" mode. Others will run and hide as soon as they hear it, shaking all over.
Without deliberately stressing out your dog, try to identify what triggers the reaction:
If its the sound then I would start by possibly recording it and then playing it back quietly, rewarding the dog if he stays calm
If its the movement, make sure the hoover is never directed towards the dog
Try to ascertain if being further away helps your dog to stay calm
The video below shows one of my foster dogs who was attacking the vacuum cleaner. By allowing her time and space to explore without pressure and then showing her that I wanted her to stay on her bed whilst I hoover, she has now learned to stay calm and is no longer in attack mode!
This same approach will work for other things that your dog is anxious about for example:
The washing machine, or other noisy appliances, you can redirect them away
If you dog reacts to the TV and barks at images on the screen
Or perhaps its the lawnmower, or the hosepipe in the garden?