@Sebastian-Roth
DC synchronize time only with computers added in AD but FOGClient can’t add computer in AD…
I found a solution by synchronizing time just before the sysprep command.
edit: I finally installs the client after deploying the post via a script called by unattended file.
Following a discussion with @Sebastian-Roth, we finally found it!
The problem is the speed negotiation with the switch . I’ll update the firmware of the switches and make feedback.