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Public Network Provider

DO NOT USE (for now)

Working with flat network providers messed up the networking on the host machine. The production setup will use vlan so there is not much sense to continue insisting on this setup.

Key Steps Overview

  • Admin creates the public network provider (flat network with the 81.196.110.112/28 subnet).
  • Admin creates a shared router that connects to the public network (consuming only one public IP).
  • Tenants create private local-net networks for their VMs.
  • Tenants allocate floating IPs from the public provider network to their VMs for direct internet access.

Step-by-Step Configuration

Step 1: Admin Creates the Shared "Public" Network Provider

The admin creates the public network provider that assigns IPs from the 81.196.110.112/28 range.

Go to Admin > Networks > Create Network:

Field Value
Name: public
Project: admin
Provider Network Type: flat
Physical Network: public
Enable Admin State: Checked
Shared: Checked
External Network: Checked
Create Subnet: Checked
Availability Zone: nova
MTU leave_empty

Warning

public has to be defined in the provider_networks section in the openstack_user_config.yml

Field Value
Subnet Name: public-subnet
Network Address: 81.196.110.112/28
IP Version: IPv4
Gateway IP: 81.196.110.113
Disable Gateway: Unchecked
Field Value
Enable DHCP Checked
Allocation Pools: 81.196.110.118,81.196.110.126
DNS Name Servers: 1.1.1.1
Host Routes: leave_empty

Warning

The public network (81.196.110.112/28) is not managed by an external router (e.g., FortiGate router). DHCP should be checked for the public-subnet

This network is shared among all tenants, allowing their routers to connect to the public network.

Equivalent CLI Command 

openstack network create office\
      --project admin \
      --share \
      --external \
      --provider-network-type flat \
      --provider-physical-network office


openstack subnet create public-subnet\
      --project admin \
      --network public \
      --subnet-range 81.196.110.112/28 \
      --gateway 81.196.110.113 \
      --dns-nameserver 1.1.1.1 \
      --allocation-pool start=81.196.110.118,end=81.196.110.126

Step 2: Admin Creates the Shared "Public" Router

Field Value
Router Name: public-router
Project: admin
Enable Admin State: Checked
External Network: public
Enable SNAT: Checked
Availability Zone Hints: nova 
openstack router create public-router \
  --project admin \
  --external-gateway public \
  --enable-snat \
  --availability-zone-hint nova