How to Add Additional Provider IP Blocks

Introduction

With OpenMetal Private Clouds, multiple provider IP blocks are supported. This guide explains how to add an additional provider IP block and add it to your cloud as a subnet.

What is a provider IP block?

This is a public subnet that is associated with your cloud's External OpenStack network. Your cloud comes with a single provider subnet by default. Floating IPs are assigned from this network. This is the subnet you would typically use to route public internet traffic to VMs in your cloud.

Add the IP block

To add a new provider IP block, first follow this Central guide: Adding new IP Blocks to a Cloud's External Provider Network

Create the subnet in OpenStack

Once the order completes, add the block to the External network as a new subnet. Log in as a user with the administrator role, typically admin.

Use these values, shown for the example block 10.0.0.112/28. On a live cloud the block is a public range.

Field	Value	Example
Subnet Name	Internet_ followed by a number	Internet_2
Network Address / CIDR	The block	10.0.0.112/28
IP Version	IPv4	IPv4
Gateway IP	First usable address	10.0.0.113
DHCP	Enabled	Enabled
Allocation Pools	Fourth usable address to the last usable address	10.0.0.116,10.0.0.126
DNS Name Servers	One per line	1.1.1.1 and 8.8.8.8

Horizon

Step 1 -- Go to Project -> Network -> Networks, click the External network, choose the Subnets tab, and click Create Subnet.

Step 2 -- On the Subnet tab, enter the name, network address, IP version, and gateway IP. Click Next.

Figure 1: Create Subnet

Step 3 -- On the Subnet Details tab, leave Enable DHCP checked and enter the allocation pool and DNS name servers. Click Create.

Figure 2: Subnet Details

Step 4 -- Confirm the new subnet is listed.

Figure 3: Subnets of the External network

Skyline

Step 1 -- Switch to the Administrator console, go to Network -> Networks, click the External network, choose the Subnets tab, and click Create Subnet.

Step 2 -- Enter the subnet name, select the admin project, and enter the IP version, CIDR, and gateway IP.

Figure 1: Create Subnet

Step 3 -- Leave DHCP enabled, enter the allocation pool and DNS servers, and click OK.

Figure 2: Allocation Pools and DNS

Step 4 -- Confirm the new subnet is listed.

Figure 3: Subnets of the External network

Reserved addresses

Each provider block reserves its first three usable addresses for the OpenMetal routers upstream of your cloud. They must stay outside the allocation pool.

Address	Example	Use
Network address	.112	Not usable
First usable	.113	Gateway, a virtual IP shared by the two routers over VRRP
Second usable	.114	First router
Third usable	.115	Second router
Fourth usable to last usable	.116 - .126	Allocation pool
Broadcast address	.127	Not usable

A /28 leaves 11 addresses for your cloud. Neutron uses some of these for its own ports, such as DHCP and metadata, so a new subnet shows addresses in use before you assign any.

Using the new IPs

When creating a resource that needs an IP from this block, such as a floating IP or a router gateway, select the new subnet.