Migration to 4.x version from a qualified 3.11.x version takes significantly longer on SV1800 than 15 minutes mentioned in the Release Notes.
We also assume the migration steps were followed exactly as specified in the Release Notes and the device was rebooted using platform reboot CLI command and not via GUI.
The last visible output on the console may look as follows:
If a monitor is connected to the device, the following message would appear:
The issue is SV1800 specific.
The device has just 1GB DOM (Disk On Module) which can't accommodate multiple system images. 4.x must be started off the SSD device, but the SSD boot option gets lost from the BIOS boot device list during the migration process.
As of Mar 14 2017, this is expected to be fixed in SW release 188.8.131.52.