# creating taps cause network flap, broadcom don't



## paw (Sep 17, 2020)

I have two servers, one with intel (igb) and one with broadcom (bge).

Server1: Intel(R) PRO/1000 PCI-Express Network Driver
Server 2: Broadcom NetXtreme Gigabit Ethernet
Version: FreeBSD 12.2-BETA1 FreeBSD 12.2-BETA1 r365618 GENERIC  amd64

I've setup a bridge for bHyve however whenever I start a new Virtual Machine on the server with the Intel chipset, I get brief network flap

Server 1:


> igb3: link state changed to UP
> tap0: link state changed to DOWN
> igb3: link state changed to DOWN
> igb3: link state changed to UP



Meanwhile with Broadcom, I don't


> tap0: link state changed to DOWN
> tap0: Ethernet address:
> tap0: promiscuous mode enabled
> nd6_dad_timer: cancel DAD on tap0 because of ND6_IFF_IFDISABLED.
> tap0: link state changed to UP



Anything I can do to diagnose this further?


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