PXE booting into a Hyper-V 2012 R2 instance - slows to a crawl?

[Karl Pielorz]

Hi,

We just updated our Windows Server 2012 test setup here to Windows Server 
2012 R2 (i.e. using Hyper-V 2012 R2 now).

We are creating new Hyper-V instances using our PXE boot environment (which 
boots you into a FreeBSD 9.1 amd64 O/S) - we'd build a Hyper-V aware kernel 
etc. from that (after SVN'ing the latest Hyper-V project source).

Hyper-V would take seconds to boot this - but since changing over to R2 it 
takes a 'very, very long time'.

The initial PXE bit happens quickly (i.e. seeing the server, and getting 
the BTX output out) but then it gets stuck with the \ spinner - it'll spin 
for a short time, stop, spin again for a short time, stop again.

It *does complete* if you leave it - but it takes minutes (e.g. around 5-10 
minutes!).

This is with creating a 'Generation 1' Hyper-V instance - and replacing the 
'Network Card' (which is added by default) with the 'Legacy Network Card'.

Anyone noticed anything similar?

-Karl