Sprinklers are very common, mostly dry-pipe systems to avoid water leakage. There are some alternatives like HI-FOG, which uses less water and therefore may do less damage to the room's equipment.
It is very undesirable for the equipment in the room to get wet. A sprinkler activation generally results in partial or total loss of the equipment in the room, and even if you can get stuff running again, it's going to take a while. However, it's even less desirable for people to die or the building to burn down.
Fire suppression systems that operate by removing oxygen from the room (such as Halon) can kill people who are trapped inside. I haven't seen a facility with this type of system in a long time.
Also, most datacenters have very strict rules about flammable material (like cardboard) on the datacenter floor. Most sites aren't super diligent about enforcing it, but just having the rules shifts the blame onto you. Imagine being on the hook financially for tens of thousands of servers because something caught on fire in your cage.
It is very undesirable for the equipment in the room to get wet. A sprinkler activation generally results in partial or total loss of the equipment in the room, and even if you can get stuff running again, it's going to take a while. However, it's even less desirable for people to die or the building to burn down.
Fire suppression systems that operate by removing oxygen from the room (such as Halon) can kill people who are trapped inside. I haven't seen a facility with this type of system in a long time.
Also, most datacenters have very strict rules about flammable material (like cardboard) on the datacenter floor. Most sites aren't super diligent about enforcing it, but just having the rules shifts the blame onto you. Imagine being on the hook financially for tens of thousands of servers because something caught on fire in your cage.