FAQs

What does "Primary IP for future server only" mean when I look at a subnet's IP addresses?

Primary subnets are assigned and removed as needed by IBM Cloud for other resources you order, such as bare metal servers or virtual server instances. IP addresses are not assigned one at a time. We assign a subnet, meaning that there is sometimes additional room for future resources. This designation is stating that these addresses will be used by future resources. See Can I use the other IP addresses that are defined by the primary subnets I see? for reasons why you should not consider these usable IP addresses.

Can I use the other IP addresses that are defined by the primary subnets I see?

No. We realize you see the primary subnets that are assigned by IBM Cloud as any other subnet, but as described in About subnets, primary subnets are what provide IP addresses to resources on demand. We assign and remove primary subnets as we require to fulfill other products. If you attempt to use unassigned IP addresses from primary subnets, we will inevitably assign them to another resource at some point. This leads to IP conflicts on the network and general service disruption. We reserve the right to block or otherwise make unusable any IP address on a primary subnet, which is not assigned during fulfillment of other products. It is recommended you use secondary subnets for all additional IP (application/service) address needs. Secondary subnets are much more flexible and are maintained on your account for as long as you own them.

Is there a way to specify which subnet I want to use for my device when I order it?

Yes, you can specify a certain subnet during the ordering process. When ordering a device, this option is available at the end of the order form. After selection of a private VLAN, a list of primary subnets that are routed to that VLAN is presented. You can select a subnet. The same process can be repeated for the public VLAN and subnet.

It is important to note that submission of the order does not guarantee that an IP address is available in the requested subnet. If no addresses are available, you are contacted to determine a course of action. For the best IBM Cloud experience, selection of a subnet is discouraged for typical uses.

I ran out of IP addresses, now what?

We automatically assign primary subnets to make more IP addresses available to fulfill your compute purchases. If you are out of primary subnet space, more primary subnet space is added automatically for you when you order more devices without specifying a specific subnet.

If you are out of secondary subnet space, such as for local virtual machines, you can order more secondary subnets.

How do I assign more IP addresses to a compute resource?

Purchase a secondary subnet. After you have a subnet that is routed to the IP address or VLAN you want, you'll want to refer to the specific compute documentation for how to set up your new IP addresses:

• Bare Metal Server IP address assignment
• Virtual Server Instance IP address assignment

What does "Reserved for HSRP" when I look at a subnet's IP addresses mean?

In some locations, IBM Cloud has routers using a technique that is known as Hot Router Standby Protocol (HSRP). Specifically, the way it's used impacts the IP addresses available to secondary portable subnets, meaning that you lose access to two more addresses in these locations. "Reserved for HSRP" indicates these IP addresses are reserved to fulfill the needs of HSRP. You might even have subnets on the same router, some with and some without, such reservations. As with any IP conflict, do not attempt to use these addresses or you risk affecting traffic on the entire subnet.

Can I order secondary subnets that are unrouted?

Yes. When ordering a secondary subnet, you can choose Unrouted as the routing type. The unrouted secondary subnet delivered is bound to the single data center you chose when ordering and will be unusable until routed by you. Unrouted secondary subnets are billed the same as routed secondary subnets, and re-routing by you has no effect on billing.

How long can unrouted subnets remain unused on my account?

Starting November 30, 2022, secondary subnets that remain unrouted on your account for 60 days or more are subject to automatic cancellation of billing and reclaim of the subnet in order to maintain sufficient subnet availability for all customers.

Can I re-route static or portable secondary subnets on my account?

Yes. Unrouted, static, and portable secondary subnets on your account can be re-routed by you. See Re-routing secondary subnets for more information on how to re-route your secondary subnets, and the limitations that exist when doing so.

How long does it take for my new global IP to appear on my account after it's ordered?

It takes approximately five minutes for a global IP to appear after it is ordered.

Can I convert one of my pre-existing static IP addresses to a global IP?

No. IBM Cloud requires all global IP addresses to be newly provisioned IP addresses, so we don’t allow pre-existing IP addresses to be converted into global IP addresses.

How long does it take for my global IP to associate to an instance?

The time that it takes for your global IP to associate depends on if you are associating a global IP for the first time, or if you are transferring it to a new instance. For new global IP addresses, it takes approximately five minutes before the address can be linked to an instance. When transferring an existing global IP between instances, it takes less than one minute.

What types of subnets are available with global IP addresses?

We currently offer global IP addresses as both IPv4 addresses and IPv6 addresses. Our global IPv4 addresses are available as single /32 addresses, while our global IPv6 addresses are available as single /64 addresses.

Can IPv4 and IPv6 global IP addresses be used interchangeably?

Because of incompatibility between IP address styles, you cannot use IPv4 and IPv6 global IP addresses interchangeably.

Can I transfer portable subnet IP addresses between servers?

Yes. When transferring an IP address from one server to another, make sure that a gratuitous ARP packet is sent. This action allows IBM Cloud's routers to update the ARP entry and forward traffic to the correct server. Not doing so might result in up to a 4-hour delay in the new server receiving traffic for the transferred address.