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Date: Thu, 5 Nov 2015 08:33:23 +0600
From: Victor Sudakov <vas@mpeks.tomsk.su>
To: John Nielsen <lists@jnielsen.net>
Cc: freebsd-net@freebsd.org
Subject: Re: tap(4) and host-only networking between host and guest
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John Nielsen wrote:
> >>>> 
> >>>> I am experimenting with bhyve which uses tap(4) for network access.
> >>>> 
> >>>> I don't want to bridge tap0 with any of the hosts's real NICs. How can
> >>>> I create a private network just between the host and the guest?
> >>> you are thinking too hard!
> >>> 
> >>> tap IS the interface..
> >>> 
> >>> ifconfig tap0 $address...
> >>> and in the VM, ifconfig vtnet0 ${some_other_address}
> >> 
> >> Thank you, Julian! It works. I felt I was missing something obvious. 
> > 
> > For some reason, after a guest is shutdown or rebooted, the IP address
> > on the host's tap0 interface is deleted.
> > 
> > It's kind of inconvenient. 
> 
> What I have done in this scenario is create a bridge interface,
> assign the host???s IP to the bridge, and add the tap as a member to
> the bridge.

That's what I have eventually done too. This way several guests can
share a LAN emulation, and a DHCP server can listen on bridge0.

-- 
Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
sip:sudakov@sibptus.tomsk.ru