On 10/27/14 09:21, John Baldwin wrote:
> On Friday, October 24, 2014 04:08:27 PM Pete Wright wrote:
>> Hi All,
>> Has anyone deployed bhyve using NAT'd or private network setups?  I've
>> been able to deploy bridged interfaces, but I was wondering if anyone
>> has done other network topologies.  Is there anything preventing this
>> from happening code wise?  I reckon it could be achieved by creating a
>> pseudo interface?
> I setup a bridge on my laptop and add all the tap interfaces for VMs as 
> members to the bridge.  I use a /24 for the internal "LAN" for these 
> interfaces and assign the .1 to the bridge0 interface itself.  I then run 
> dnsmasq to provide DHCP/DNS to the VMs and use natd (ipfw_nat would also 
> work) 
> to allow the VMs NAT access to the outside world.  There are more details in 
> an article in the most recent issue of the FreeBSD Journal, but I'll push 
> that 
> into the regular FreeBSD docs at some point as well.
> With the dnsmasq setup, I put the vmname as the hostname so that it is sent 
> in 
> the dhclient request.  dnsmasq then adds local overrides for VMs while they 
> are active.  (So you can 'ssh vm0' on the host, or from another vm.)  The 
> 'host' entry in /etc/hosts is also snarfed up by dnsmasq so that within a vm 
> I 
> can use 'host' as a hostname (e.g. for NFS mounting something off of my 
> laptop).
> Some config file snippets:
> /etc/sysctl.conf:
> net.link.tap.up_on_open=1
> /etc/rc.conf:
> # bhyve setup
> autobridge_interfaces="bridge0"
> autobridge_bridge0="tap*"
> cloned_interfaces="bridge0 tap0 tap1 tap2"
> ifconfig_bridge0="inet"
> gateway_enable="YES"
> natd_enable="YES"
> natd_interface="wlan0"
> dnsmasq_enable="YES"
> firewall_enable="YES"
> firewall_type="/etc/rc.firewall.pippin"
> /etc/hosts:
>            host
> /etc/resolvconf.conf:
> name_servers=
> dnsmasq_conf=/etc/dnsmasq-conf.conf
> dnsmasq_resolv=/etc/dnsmasq-resolv.conf
> /usr/local/etc/dnsmasq.conf:
> domain-needed
> bogus-priv
> resolv-file=/etc/dnsmasq-resolv.conf
> interface=bridge0
> dhcp-range=,,12h
> conf-file=/etc/dnsmasq-conf.conf
> /etc/rc.firewall.pippin:
> # prevent inbound traffic for our guest /24
> add     deny    all from any to via em0
> add     deny    all from any to via wlan0
> # divert packets between guest and outside world to natd
> add     divert  natd all from any to any via wlan0
> # prevent outbound traffic for our guest /24
> add     deny    all from to any via em0
> add     deny    all from to any via wlan0
> # pass everything else
> add     allow   all from any to any
> (I have not figured out a way to have the NAT prefer em0 if present and fail 
> over to wlan0 if not, etc.)

Thanks for this detailed explanation John!  Using dnsmasq sounds great,
especially for my environment since we already leverage it for openstack
on our linux systems extensively.


Pete Wright
twitter => @nomadlogicLA

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