Hetzner, save IPv4 addresses for XenServer virtual machines

A small life hack that you can use if you want to save some IPv4 addresses on your virtual machines in XenServer (it doesn't matter).

After you have installed Hetzner'en XenServer or another OS on the server, you get 1 IP address, mask and gateway. Since virtual machines require separate addresses, you have the opportunity to order them:


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For example, we were allocated 46.4.205.64/29. How to use all 8 addresses? About this below.

On XenCenter we create an additional network:







Assign dom0 in this subnet to an address from a range of private addresses (in this case, 172.16.1.1/24):



When creating a new VM in the configuration process, we indicate that the network will be the newly created Network 1:



Installing the OS in a virtual machine can cause some inconvenience if it needs the Internet. Therefore, for Linux distributions, it is recommended to use full images, rather than netinstall. However, it is always possible to order one additional IP for such needs, and use it at the time of installation (respectively via Network 0).

In the process of installing the OS when setting up the network, specify the IP from the above range (in this case, 172.16.1.0/24), for example, 172.16.1.10/24 without specifying a gateway .

After installation, let's assign the address 46.4.205.64 to our virtual machine:

- in the network interface settings (for example in debian):


- and write the route at startup:


not forgetting #chmod + x /etc/network/if-up.d/route

With this, the virtual machine network setup is complete. It remains to correct the routing to dom0.

Determine the uuid of our network (Network 1):

#xe network-list

Add a static route to our subnet:

#xe network-param-set uuid = uuid other-config: static-routes = 46.4.205.64 / 29 / 172.16.1.1

Check:


Well, in conclusion:


The solution is not tied to a specific routing platform and OS in virtual machines, just at hand was such a set of software. The only question is how to implement it with a Windows virtual machine. Perhaps in the comments prompt.

Save addresses and thank you for your attention.