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| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information# |
| regarding copyright ownership. The ASF licenses this file |
| to you under the Apache License, Version 2.0 (the |
| "License"); you may not use this file except in compliance |
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| http://www.apache.org/licenses/LICENSE-2.0 |
| Unless required by applicable law or agreed to in writing, |
| software distributed under the License is distributed on an |
| "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| KIND, either express or implied. See the License for the |
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| |
| |
| Persistent Networks |
| ------------------- |
| |
| The network that you can provision without having to deploy any VMs on |
| it is called a persistent network. A persistent network can be part of a |
| VPC or a non-VPC environment. |
| |
| When you create other types of network, a network is only a database |
| entry until the first VM is created on that network. When the first VM |
| is created, a VLAN ID is assigned and the network is provisioned. Also, |
| when the last VM is destroyed, the VLAN ID is released and the network |
| is no longer available. With the addition of persistent network, you |
| will have the ability to create a network in CloudStack in which |
| physical devices can be deployed without having to run any VMs. |
| Additionally, you can deploy physical devices on that network. |
| |
| One of the advantages of having a persistent network is that you can |
| create a VPC with a tier consisting of only physical devices. For |
| example, you might create a VPC for a three-tier application, deploy VMs |
| for Web and Application tier, and use physical machines for the Database |
| tier. Another use case is that if you are providing services by using |
| physical hardware, you can define the network as persistent and |
| therefore even if all its VMs are destroyed the services will not be |
| discontinued. |
| |
| |
| Persistent Network Considerations |
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| |
| - Persistent network is designed for isolated networks. |
| |
| - All default network offerings are non-persistent. |
| |
| - A network offering cannot be editable because changing it affects the |
| behavior of the existing networks that were created using this |
| network offering. |
| |
| - When you create a guest network, the network offering that you select |
| defines the network persistence. This in turn depends on whether |
| persistent network is enabled in the selected network offering. |
| |
| - An existing network can be made persistent by changing its network |
| offering to an offering that has the Persistent option enabled. While |
| setting this property, even if the network has no running VMs, the |
| network is provisioned. |
| |
| - An existing network can be made non-persistent by changing its |
| network offering to an offering that has the Persistent option |
| disabled. If the network has no running VMs, during the next network |
| garbage collection run the network is shut down. |
| |
| - When the last VM on a network is destroyed, the network garbage |
| collector checks if the network offering associated with the network |
| is persistent, and shuts down the network only if it is |
| non-persistent. |
| |
| |
| Creating a Persistent Guest Network |
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| |
| To create a persistent network, perform the following: |
| |
| #. Create a network offering with the Persistent option enabled. |
| |
| See `"Creating a New Network Offering" |
| <networking.html#creating-a-new-network-offering>`_. |
| |
| #. Select Network from the left navigation pane. |
| |
| #. Select the guest network that you want to offer this network service |
| to. |
| |
| #. Click the Edit button. |
| |
| #. From the Network Offering drop-down, select the persistent network |
| offering you have just created. |
| |
| #. Click OK. |