This figure consists of two figures that are side by side. The figure on the left shows an active-active system. There are two computers, Node 1 and Node 2, in the active-active system figure. Both Node 1 and Node 2 are active at the same time, and they both actively process client requests they receive.
The figure on the right shows an active-passive system. There are two computers, Node 1 and Node 2, in the active-passive system figure. In the active-passive system, Node 1 is active and processes all the client requests. Node 2 is passive. When Node 1 fails, Node 2 is brought up and becomes active, processing client requests.