VIMAGE

[Joe]

Pietro Paolini wrote:
> Hello all,
> 
> I am a new bye on the FreeBSD and I am looking at the VIMAGE features experiencing some problems.
> I added the options :
> VIMAGE
> if_bridge
> 
> and I removed
> STCP
> 
> then I recompiled my kernel and install it.
> 
> After that, following this tutorial http://imunes.tel.fer.hr/virtnet/eurobsdcon07_tutorial.pdf I tried the "Exercise 2" which consist on 
> the following commands:
> 
> vimage -c n1
> vimage -c n2
> ngctl mkpeer efface ether ether
> ngctl mkpeer efface ether ether
> ngctl mkpeer em0: bridge lower link0
> ngctl name em0:lower bridge0
> ngctl connect em0: bridge0: upper link1
> ngctl connect ngeth0: bridge0: ether link2
> ngctl connect ngeth1: bridge0: ether link3
> vimage -i n1 ngeth0 e0
> 
> But my virtual interface on the n1 vimage does not receive any packet from the external network while I can see the packet go out from it.
> 
> For instance using DHCP, e0 on n1 sends DHCP packets but it does not receive the answers (which are send, I verified it from wireshark), in adding
> the ARP request for his IP address (if I try to add it statically) are not received then it can not answer.
> 
> At the end of the line the question is: how can I make this "virtual network" and the external real network be able to communicate ?
> 
> Thanks in advance.
> Pietro.
> 
> 

1. That link is from 2007. So very much has changed since then.
There are more current links on the internet about this subject. Most 
are for 8.X releases.

2. If your running 8.2-RELEASE or 9.1-RELEASE all you need to add is 
"options vimage" statement to your kernel source and recompile.

3. There are 2 networking methods available for creating vnet/vimage 
jail networks, if_bridge/epair and netgraph. The if_bridge/epair method 
is far simpler to config and use then the netgraph method.

4. There are 2 methods of jail setup, the rc.d method where your jail 
definition parameters go into the hosts rc.conf and the jail(8) method 
where you can place each jails definition parameter in separate files.

5. There are two very important show stopper PRs on vimage,
164763 memory leak and 149050 the rc.d keyword "nojail" problem.
Vimage is a very long way from prime time usage, thats why it's labeled 
as highly experimental. Host system freezes and page faults are common.

6. When it comes to running a firewall in a vnet/vimage jail your 
limited to IPFW and it has limitations. Dummynet and in kernel NAT cause 
system freezes. IPFILTER causes page fault at boot time. PF will run on 
the host but not run in the vnet/vimage jail. Here are a bunch of PRs on 
vimage firewall problems, 143621, 176092, 161094, 176992, 143808, 
148155, 165252, 178480, 178482


Check out these links

http://druidbsd.sourceforge.net/vimage.shtml
http://devinteske.com/vimage-jails-on-freebsd-8
http://lists.freebsd.org/pipermail/freebsd-virtualization/2011-September/000747.html

http://bsdbased.com/2009/12/06/freebsd-8-vimage-epair-howto
http://zewaren.net/site/?q=node/78