Hello to mikrotik forum, I face the following problem. I run a force self bgp between a 911 5hpnD (level 3 routerOs 6.17) and a hap using ethernet, port 3 specifically in HAP ( routerOs 6.29) . Periodically the bgp between these two devices drops. If I disable and then enable bpg does not connects. The only solution is to reboot 911. Then after an hour or a week it drops again. I did several tests, I chagle timers from 3 , 1 to 3, 10 but no solution. I disable in advanced properties update source from ehternet 3 to none in Hap (this worked for one week). I do not know what to do, please find a solution because it is very annoying to reboot 911 every 10 minutes.
First thing I’d try is upgrading both to latest bugfix-only release, 6.32.3 as of this time. Make sure both devices have firmware up to date also.
I make the following test, I change ethernet speed from Auto Negotiation to 10 mbps full duplex in both devices. That worked , I made many bandwith tests and It was stable 9.7 mbps to tx and also to rx. When I changed to 100 mbps the bandwidth test lasted a few seconds. I don’t know what is going on. After rebooting 911 bgp wakes up again.
Have you checked your RouterOS and firmware versions? System > Routerboard
My current firmware in 911 5HPnD is 3.19 , version is 6.19, I upgraded it from 6.17. In hap firmware is 3.24 version is 6.29.1. BGP is not stable. It brakes and I do not know why 
Is this a Hap or Hap lite? Have you checked memory usage when BGP breaks?