Adding a Skytap-managed DNS name and public IP address to a VM

A public IP address exposes all network ports on the VM, allowing direct inbound and outbound access from the public Internet.

Public IP address access may be disabled by your administrator.

Because there is a greater security risk in exposing a VM to the public Internet, consult your network administrator before using a public IP address. To learn more about other options for sharing a VM with external users, see Accessing VM desktops.


How to attach a dynamic public IP address with DNS to a VM

To add a managed DNS name and dynamic public IP address to a VM
  1. Navigate to the Environment page.

    Environment Details page

  2. Navigate to the VM Settings > Network Adapters page for the VM you want to edit.

  3. Click Add Public IP with DNS.

    Public IP addresses can’t be attached to network adapters on Manual networks. If Add Public IP with DNS is missing, create an automatic network, attach the VM to it, and then repeat the steps above to add the public IP address on the new network adapter.

  4. Skytap automatically:

    show public IP addresses

    If the VM is suspended or powered off, Skytap generates the DNS name but doesn’t attach a public IP address. The next time the VM is run, an available public IP address will be automatically attached to the VM. The DNS name isn’t accessible unless the VM is running.

  5. You may need to configure the VM guest OS to accept incoming connections. A guest OS typically has a software-based firewall that blocks most connections to a VM by default. You may not be able to connect to the VM from the public Internet unless you change the firewall rules to allow incoming connections.

Also see Protecting a VM that is exposed to the internet or compromised.

Accessing the VM via its DNS name and/or dynamic public IP address

When the VM is running, it’s accessible from the public Internet via the DNS name listed on the network adapter page. It can also be accessed via the dynamic public IP address, though this public IP address is very likely to change the next time the VM is run.

Notes about connecting to the public IP address from:

  • Within the VM

    Skytap routes traffic from the public IP address to the VM local IP address via Network Address Translation (NAT). Within the VM, the public IP isn’t visible to the guest OS or applications running on the VM. For example, if you’re logged into a firewall appliance VM that is attached to a public IP address, you’ll need to access the appliance’s web interface from the VM local IP address (example:

  • Other VMs in the same environment

    Generally, a VM can’t ping a public IP address that is attached to another VM in the same environment. VMs on the same network must communicate with one another using their private network IP addresses. For more information, see Can I connect to a public IP address or published service from another VM in the same environment?


Can I attach a public IP address to a VM that is also connected to a VPN or Virtual Private Network?

Yes. Public IP addresses can be added to an environment that is connected to a VPN or Virtual Private Network (WAN). You should exercise caution to prevent security issues from exposing the environment and WAN to the public Internet.

Related links: Managing VPNs and Private Network Connections, Exposing and blocking public internet access, Protecting a VM that is exposed to the internet or compromised, and Managing public IP addresses.

What happens when I save the VM in a template?

Skytap automatically generates a unique domain name for each new VM created from the template. When the new VM is run, Skytap automatically deploys an available public IP address.

See also