From owner-freebsd-virtualization@FreeBSD.ORG  Fri Jun 28 17:29:52 2013
Return-Path: <owner-freebsd-virtualization@FreeBSD.ORG>
Delivered-To: freebsd-virtualization@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by hub.freebsd.org (Postfix) with ESMTP id 01D2D8C6
 for <freebsd-virtualization@freebsd.org>; Fri, 28 Jun 2013 17:29:51 +0000 (UTC)
 (envelope-from grehan@freebsd.org)
Received: from alto.onthenet.com.au (alto.OntheNet.com.au [203.13.68.12])
 by mx1.freebsd.org (Postfix) with ESMTP id BA2BA1A42
 for <freebsd-virtualization@freebsd.org>; Fri, 28 Jun 2013 17:29:51 +0000 (UTC)
Received: from dommail.onthenet.com.au (dommail.OntheNet.com.au [203.13.70.57])
 by alto.onthenet.com.au (Postfix) with ESMTPS id 0FCE812269;
 Sat, 29 Jun 2013 03:29:51 +1000 (EST)
Received: from Peter-Grehans-MacBook-Pro.local ([64.245.0.210])
 by dommail.onthenet.com.au (MOS 4.2.4-GA)
 with ESMTP id BMZ71348 (AUTH peterg@ptree32.com.au);
 Sat, 29 Jun 2013 03:29:50 +1000
Message-ID: <51CDC80C.7070709@freebsd.org>
Date: Fri, 28 Jun 2013 10:29:48 -0700
From: Peter Grehan <grehan@freebsd.org>
User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US;
 rv:1.9.2.28) Gecko/20120306 Thunderbird/3.1.20
MIME-Version: 1.0
To: Aryeh Friedman <aryeh.friedman@gmail.com>
Subject: Re: questions on if_bridge and if_tap
References: <CAGBxaXnVms5nLihEE7EgOLs0MsUM9nvM+Lwd0s8s=BekfM=Ydg@mail.gmail.com>
In-Reply-To: <CAGBxaXnVms5nLihEE7EgOLs0MsUM9nvM+Lwd0s8s=BekfM=Ydg@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Cc: freebsd-virtualization@freebsd.org
X-BeenThere: freebsd-virtualization@freebsd.org
X-Mailman-Version: 2.1.14
Precedence: list
List-Id: "Discussion of various virtualization techniques FreeBSD supports."
 <freebsd-virtualization.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-virtualization>, 
 <mailto:freebsd-virtualization-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-virtualization>
List-Post: <mailto:freebsd-virtualization@freebsd.org>
List-Help: <mailto:freebsd-virtualization-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization>, 
 <mailto:freebsd-virtualization-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 28 Jun 2013 17:29:52 -0000

> 1. Is there a upper limit on the number of bridges and/or taps and if
> so what is it?

  The if_index field for an interface is 16 bits so I guess there may be 
an upper bound of 64K. That might start to stretch limits of FreeBSD in 
other areas.

> 2. Does each tap need a corresponding bridge or can they all go
> through the same bridge?

  They can all go through the same bridge if that's what you want (the 
same broadcoast domain).

later,

Peter.