--- Comment #34 from [hidden email] ---
(In reply to Eitan Adler from comment #33)
Hi - this issue still exists, I've just re-tested in 10.4 and 11.1. I'm not
able to test 12.x at the moment, but I have no reason to believe it's been
fixed in current or anything.
It affects anything working with 'low level' packets - so NAT, OpenVPN, DHCP
et'al. - e.g. with OpenVPN it seems packet coalescing 'behind the scenes' ends
up presenting way over 1500 byte packets to OpenVPN - which it point blank
refuses to handle.
Workaround we're using here is to set 'hw.xen.disable_pv_nics=1' in
/boot/loader.conf on FreeBSD with a small mod to 'qemu-dm-wrapper' on the Xen
Server, and a custom field added to affected VM's in XenCenter that the wrapper
'keys off' - this turns xn0 into vtnet0 for these hosts - these do work with
the above applications, and are still live-migratable (and appear to be better
performance than re0 NIC's).