What is the difference between static public IP addresses and dynamic public IP addresses with DNS?

Skytap Cloud offers two options for attaching a public IP to a VM:

  • Add static IP address directly exposes the VM to the public Internet via an IPv4 static IP address.

    Example: 188.188.188.188

  • Add Public IP with DNS directly exposes the VM to the public Internet via a static, fully qualified domain name (FQDN) and dynamic (revolving) public IP address. The FQDN is managed by the Skytap Cloud DNS service.

    Example FQDN: app1.sampleorg.skytapdns.com

The table below describes additional differences between these two options.

Static public IP address

Dynamic public IP address with DNS

Who manages the IP address assignment?

Users and admins play different roles in the process:

  • Admins manage the availability of static public IP addresses by adding static public IP addresses on the IP management page.
  • Users manually attach static public IP addresses to their VMs.
  • Users and admins manage the availability of static IP addresses (either by suspending a VM to pass control of the public IP address to another VM, or by detaching a public IP address so it can be used by another resource)

Skytap Cloud dynamically manages the public IP address assignment for VMs with dynamic public IPs and DNS names. Skytap Cloud manages the DNS name.

  • When you run the VM, Skytap Cloud automatically attaches an available public IP address.
  • When you suspend or shut down the VM, Skytap Cloud automatically releases the public IP address.

The VM is not dependent on the availability of a specific public IP address; it can use any available public IP address.

See also: How does Skytap Cloud generate the VM DNS name?

Does the public IP remain attached to the VM through runstate changes?

Yes

A static public IP address remains attached to the VM, even when the VM is suspended or shut down. The public IP address must be manually detached when it is no longer needed.

No.

The dynamic public IP address is released when the VM is suspended or shut down. The next time the VM is a run, a new dynamic public IP address is assigned.

Best for…

VMs with a need for a single defined and specific IP address.

For example, VMs used as network endpoints.

When accessing a VMs through a domain name is optimal.

For example, VMs used during a demo or training session.

Can an IP address be attached to multiple VMs at the same time?

Yes, but only one of those VMs can run at a time.

No.

Each VM has a unique domain name that is associated with an available public IP address at runtime.

Is the public IP address setting saved in a template?

Yes.

Skytap Cloud attaches each new VM to the same static public IP address. When the same static public IP address is attached to multiple VMs, only one of those VMs can run at a time.

Yes.

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

Skytap Cloud has other options for sharing virtual machine services and desktops with external users. For more information, see Accessing VMs.