The SMA supports the following SMA 1000 series appliances running SMA 12.4.3 firmware:
EX6000, EX7000, and EX9000 appliances cannot be upgraded to SMA 12.4.3
You can upgrade to 12.4.3 from 12.4.2, 12.4.1, and 12.1.0.
Upgrading a virtual appliance hosted on ESXI requires network adapter changes. Refer to the SonicWall Support Knowledge Base article at: https://www.sonicwall.com/support/knowledge-base/170502800288963.