No. You don't need fault tolerance. It's nice, but not necessary. How often is your VPS or colocated server going to go down, anyway? Email is meant to deal wi

No. You don't need fault tolerance. It's nice, but not necessary. How often is your VPS or colocated server going to go down, anyway? Email is meant to deal with transient issues. Web interface? Again, you don't need that at all. Constant monitoring? No. Maintenance? Certainly not constant.