Networking Infrastructure

We have two domains xen-hosting.org and xen-hosting.net which are setup and used as follows:

  • xen-hosting.org
  • xen-hosting.net
    • Used for client accounts
    • Used for client console access.

Client Access

Each client has a unique username, and their system can be accessed via:

$username.xen-hosting.net

To allow users to manage their Xen system there is a simple shell which is described more fully in the support section. This shell can be accessed via:

ssh -i $keyfile $user@$user.console.xen-hosting.net

This shell allows access to the serial console of the guest systems even if their networking is down. (Perhaps due to a broken firewall, or prior to setup.)

(SSH access to the console is only available using public key authentication; mail Steve if you have lost your key.)

Networking Details

The primary host has the following networking details:

  address   80.68.87.60
  netmask   255.255.255.0
  broadcast 80.68.87.255
  gateway   80.68.87.1

In addition to the primary systems IP address given above we have some extra IP addresses which are allocated to the Xen guests.

Combined we have been allocated: 80.68.85.32/27. This works out at 32 addresses. Unfortunately Xen 3.x only allows guest systems to be given three ethernet devices.

Each Xen guest system is supplied with three IP addressess by default - although remember support is available even if you lose access to your systems network interface(s).

Client Details

Each client has been allocated three (3) IP addresses. These IP addresses are contiguous with the userid and allocation listed below:

orebokech 80.68.85.34-46
grimoire  80.68.85.37-39
mgdm      80.68.85.40-42
nsa       80.68.85.43-45
skx       80.68.85.46-48
joey      80.68.85.49-51
cernio    80.68.85.52-54

Since Xen is limited to no more than three network devices in each guest it seems unlikely that more IPs will be allocated at this time, even though we have plenty "spare".

Reverse DNS

Clients should have full control over their IP addresses, including the setup of reverse DNS entries.

To change, or view, current reverse DNS entries use the xen-shell. The rdns command can be used to modify DNS entries

Viewing current setup:

xen-shell> rdns
80.68.85.46 skx.xen-hosting.net
80.68.85.47 skx.xen-hosting.net
80.68.85.48 skx.xen-hosting.net

Changing the reverse DNS:

xen-shell> rdns 80.68.85.46 foo.bar.com
Set the reverse DNS for 80.68.85.46 to foo.bar.com
Please wait an hour or two for it to take effect