Migration involves updating the version of the software. For a highly-available system like solidDB HotStandby (HSB), the migration can be cold or hot.
Cold migration means that you shut down the whole system (both servers), upgrade the system, and restart with new software and configuration data.
Hot migration means that you upgrade your HSB server pair without taking your entire system offline. One server can keep operating while the other server is being upgraded.
Important With hot migration, although your entire system will not be down, users or applications might have to disconnect from one server and connect to the other server if you are using basic connectivity. If you are using transparent connectivity, you can perform the hot migration transparently to users and applications.