I don’t tank much these days but as a BRD main I understand the no knock back prevention life. Generally you just want to position yourself so that you won’t fall off. As DRK you can time plunge to essentially negate the kb or use it after you’ve flown backwards to close the gap quickly. WAR can do the same with onslaught if you have gauge for it. Holmgang and Inner Release also negate kb, though you aren’t typically holding those for kbs alone. Worth noting in case a kb lines up with an IR window or buster you’ll be invulning.