Subject: Re: [vserver] adding guest interface: isn't it hotplug?
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Thu, 26 Nov 2009 21:54:17 +0100

On Thu, Nov 26, 2009 at 09:37:40PM +0100, Marc Chantreux wrote:
> hello, 

> i follow this tutorial: 

> http://linux-vserver.org/Networking_vserver_guests

> there is nothing written about the guest so i hope it's 
> hotplug and i don't need to reboot. 

no reboot is required for guest networking, neither
host nor guest side

> unfortunatly: i see no new interface in foo. 

which is expected, as Linux-VServer uses IP isolation
instead of virtual network stacks (which you can get
by utilizing the network namespaces), so the guest
will always see a subset (according to the assigned
IPs) of the host devices and IPs

> do i have to reboot foo? 

nope

> on the host machine, i can see: 
> 
> > ip link show dummy0
> 4: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN 
>     link/ether da:af:48:aa:25:95 brd ff:ff:ff:ff:ff:ff
> > sysctl net/ipv4/ip_forward                    
> net.ipv4.ip_forward = 1
> > iptables-save | grep SNAT                     
> -A POSTROUTING -s 10.0.0.0/8 -d ! 10.0.0.0/8 -j SNAT --to-source 212.85.154.29 
> > grep -R . /etc/vservers/descartes/interfaces/1
> /etc/vservers/foo/interfaces/1/ip:10.0.0.2
> /etc/vservers/foo/interfaces/1/prefix:8
> /etc/vservers/foo/interfaces/1/dev:dummy0
> /etc/vservers/foo/interfaces/1/name:virt0

with this config, if you start the guest, util-vserver
will (according to your config) create an alias
'dummy0:virt0' with the ip 10.0.0.2/8 and assign that
address to your guest

HTH,
Herbert

> regards
> 
> -- 
> Marc Chantreux
> BibLibre, expert en logiciels libres pour l'info-doc
> http://biblibre.com