Rudi Ahlers
2008-Jun-20 22:41 UTC
[Xen-users] is it a good idea to share an IP with dom0 & domU?
Hi all I wonder if someone can give me some suggestions, from experience on this. We have 4 IP''s per server, and I''d like to use them wisely. dom0 won''t really be used, other than accessing / managing / monitoring domU''s. So, is it wise to share the main IP of the server with a domU ? And from what I understand, this is bridging, right? I need to access the domU directly from the internet, via the IP that our ISP has assigned to us. -- Kind Regards Rudi Ahlers CEO, SoftDux Web: http://www.SoftDux.com Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stuff _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Nick Couchman
2008-Jun-20 22:52 UTC
Re: [Xen-users] is it a good idea to share an IP with dom0 & domU?
You can''t "share" an IP with your server. If your dom0 has an IP assigned by the ISP for you to access it to manage, you cannot assign that IP to any other domU on the system. IPs must always be unique. With bridging, each domU must have an IP that the network connected to the bridge can see. So, if your dom0 eth0 has an IP address and you set up a bridge for the domUs to access and want them to communicate with the dom0 and on the same network as the dom0, they need to be on the same subnet and have the same subnet mask. The other option is to do some sort of NAT setup using the dom0 IP address and iptables (e.g. on a Linux-based dom0) so that your domUs use NAT to see the outside world. In this setup you can use port forwarding on the dom0 to forward certain services into the domUs, but each port can only forward to a single domU. -Nick>>> On 2008/06/20 at 16:41, Rudi Ahlers <Rudi@SoftDux.com> wrote:Hi all I wonder if someone can give me some suggestions, from experience on this. We have 4 IP''s per server, and I''d like to use them wisely. dom0 won''t really be used, other than accessing / managing / monitoring domU''s. So, is it wise to share the main IP of the server with a domU ? And from what I understand, this is bridging, right? I need to access the domU directly from the internet, via the IP that our ISP has assigned to us. -- Kind Regards Rudi Ahlers CEO, SoftDux Web: http://www.SoftDux.com Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stuff This e-mail may contain confidential and privileged material for the sole use of the intended recipient. If this email is not intended for you, or you are not responsible for the delivery of this message to the intended recipient, please note that this message may contain SEAKR Engineering (SEAKR) Privileged/Proprietary Information. In such a case, you are strictly prohibited from downloading, photocopying, distributing or otherwise using this message, its contents or attachments in any way. If you have received this message in error, please notify us immediately by replying to this e-mail and delete the message from your mailbox. Information contained in this message that does not relate to the business of SEAKR is neither endorsed by nor attributable to SEAKR. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Rudi Ahlers
2008-Jun-20 23:01 UTC
Re: [Xen-users] is it a good idea to share an IP with dom0 & domU?
Nick Couchman wrote:> You can''t "share" an IP with your server. If your dom0 has an IP > assigned by the ISP for you to access it to manage, you cannot assign > that IP to any other domU on the system. IPs must always be unique. > With bridging, each domU must have an IP that the network connected to > the bridge can see. So, if your dom0 eth0 has an IP address and you > set up a bridge for the domUs to access and want them to communicate > with the dom0 and on the same network as the dom0, they need to be on > the same subnet and have the same subnet mask. The other option is to > do some sort of NAT setup using the dom0 IP address and iptables (e.g. > on a Linux-based dom0) so that your domUs use NAT to see the outside > world. In this setup you can use port forwarding on the dom0 to > forward certain services into the domUs, but each port can only > forward to a single domU. > > -Nick > > >>> On 2008/06/20 at 16:41, Rudi Ahlers <Rudi@SoftDux.com> wrote: > Hi all > > I wonder if someone can give me some suggestions, from experience on this. > > We have 4 IP''s per server, and I''d like to use them wisely. dom0 won''t > really be used, other than accessing / managing / monitoring domU''s. > > So, is it wise to share the main IP of the server with a domU ? > > And from what I understand, this is bridging, right? I need to access > the domU directly from the internet, via the IP that our ISP has > assigned to us. > > -- > > Kind Regards > Rudi Ahlers > CEO, SoftDux > > Web: http://www.SoftDux.com > Check out my technical blog, http://blog.softdux.com for Linux or > other technical stuff, or visit http://www.WebHostingTalk.co.za for > Web Hosting stuff > >ok., so you''re saying I should have 1.2.3.4 for dom0, and then 1.2.3.5 for domU, right? I''m trying to understand this whole setup still, so bear with me please :) Here''s my current setup: 1x server with 2x NIC''s (192.168.10.30 & xxx.xxxx.xxx.145). We''re going to use the 192.168.10.30 IP / subnet to communicate between servers on a VLAN in the DC. The other server runs on 192.168.10.31, and then I have setup a Linux domU with 192.168.10.32, and a Windows domU as 192.168.10.33 Our ISP has assigned us a total of 4 IP''s, which means xxx.xxx.xxx.145 is assigned to the Linux dom0 & xxx.xxx.xxx.149 to a Windows VMWare server (the 192.168.10.31 machine). I now have xxx.xxx.xxx.146 & 147 left to use on domU''s on the Linux server, and I was hoping to have a 3rd domU, using the main IP to access the domU as well. But I see that my approach was wrong, so I''ll have to rethink this a bit, thank you :) -- Kind Regards Rudi Ahlers CEO, SoftDux Web: http://www.SoftDux.com Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stuff _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users