Are you talking about the community servers available through installing the community patch from CnCNet?
https://cncnet.org/red-alert-2#download I don't think that there are official servers anymore. Anyway, I have a huge problem with playing RTS games online. That's because the difficulty level is over the roof. There are usually only veterans playing the game after all this time, so it's very noob unfriendly there. I can say however that RA2 is one of the best RTS games of all times, so no wonder that it still has an active community.