Upgrade from v10.2.4 to v12.0.0, no configuration migrates across

Did you use the 'Install Configuration' option and selected the right volume to import and convert the configuration from when using the boot location? See:

• https://support.f5.com/kb/en-us/solutions/public/14000/700/sol14704.html

You can also check the liveinstall.log at: /var/log/liveinstall.log for warning/errors during upgrade. And check if the configuration is fully loaded:

tmsh show sys mcp-state

If the configuration is not fully loaded, check why:

tmsh load sys config