For code below. (See on plantuml.com server)
First page is displayed as:
and 2nd page as
---------------------------------------------------------
@startuml
!include <office/Servers/database_server>
!include <office/Servers/application_server>
!include <office/Concepts/firewall>
!include <office/Clouds/cloud_disaster_red>
rectangle "<$database_server>\nDatabase"
newpage
rectangle "<$application_server>\nApp Server"
newpage
rectangle "<$firewall>\nFirewall"
newpage
rectangle "<$cloud_disaster_red>\nCloud"
@enduml