DECserver 90T replacement

hi all
this is my first post on here, at the company where i work we have a Digital DECserver 90 T. because of its age we would like to upgrade to something new. it has to be a direct replacement. it is currently communicating with Alpha au series servers. does anyone have any idea on what it can be replaced with? so basically what will do the same job as a Digital DECserver 90 T but is modern.

thanks in advance.