My boys have started fighting, the older one is 8 the younger one 2. Tonight it was quite nasty. I also have a 9 year old bitch.
The only thing that as changed is I lost my older bitch 3 months ago. After they have had a spat and things have calmed down they are best of buddies again. Both males are entire  because I show both of them. They are fine with other males when out and about. The fights always seem to be triggered by excitement, when I come in from work or shopping, someone knocking on the door etc i have also noticed and stopped the younger one trying to stand over the older male.
What can I do to stop this?

I'd split them up when you are not at home to play safe. I have one male who very nearly killed another when I was not at home, and two bitches who also start to fight with excitement. Both times we were just gone for no more than an hour as we'd only gone to the vet. Came home once to find blood all up the walls -thankfully it mainly originated from ears so looked worse than it was. They are now never kept together if we go out (I kennel the dog together with the bitch who is the trouble maker), and that has worked really well -the rest of the time they are fine and we don't need to worry as they are only together when we are at home.

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I'd split them up as Marianne suggests but I'd also do a lot of work on their relationship - marking and rewarding anything good between them so anything from looks, to walking past each other without reacting, to walking away from each other if they are greeting.  It makes a big difference and I find using a clicker makes it a heck of a lot quicker too.

I'd also work on rewarding calm behaviour generally so that becomes a habit to help ease the risk of them fighting due to excitement - the more self control a dog has the better the chances of calm being chosen over fighting.

I walk with a lady who had this problem and she nurtured one of her dogs and now doesn't have this problem.

neutering ( I assume that is what you meant) will only reduce fighting if it is sexually motivated, will do nothing if it is excitement, fear etc., in fact if it's fearfulness, will make it worse as testosterone is what give males most of their confidence.

I had a male, entire, who we'd run on (there were 5 puppies, all males!!) and by age 2, he started challenging his uncle for top dog.  He'd not been used at stud, but his uncle had.  I tried everything to stop him, including putting them both in an outside pen together (where i could use a hose if necessary).   They lay by the gate noses touching waiting for me to let them back indoors again.   Not a rumble.   Later on the same day he was at it again.    Finally so peace was restored to my small pack, I reluctantly had to find him another home.   He went off to live with a lovely family, and his own two bitches and was happy as larry.   We went to check after a few months - he greeted us, and turned back to what he was doing.  I hated having to do this, but it was getting increasingly worse, and I wasn't going to have my older male (not quite as old as your boy) injured.   Once he went, peace did return, frustrating as it was because I'd had entire males, with my entire bitches with none of that before.

Perhaps you may have to consider the same before they do serious injury to each other.   If you find the right home for the younger one, you could still be able to show him?

My older boy as gone to live with my daughter. My bitch also started on him. I couldn't have him here anymore, he was so unhappy and getting stressed which was also stressing me out.
I had taken him to the vets for a full check to see if anything was wrong with him, which is why they all started to attack him (even my little x started to growl) but they could find nothing wrong what so ever. I miss him so much but had to do what was right for him.
I still provide all his food, also because she is only 2 miles away i can keep his insurance going and I have seen him via FaceTime but not sure if can i go and see him? He's been gone 3 weeks now. Do you think I could one day go and see him? If so how long?

My older boy as gone to live with my daughter. My bitch also started on him. I couldn't have him here anymore, he was so unhappy and getting stressed which was also stressing me out.

I think you did a very sensible thing for all concerned, you made a very difficult decision & burden on yourself by putting their welfare first, congratulations.
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