Introduction

Purpose

Isolation of Guest VM traffic is achieved using Security Groups in Basic zone. For Advance zone, traffic can be isolated on per network basis using VLANs. Currently there is no way to isolate guest traffic within in Network.
Purpose of this document is provide functional specification to use SG to isolate guest VM within a same network in advanced zone.

Glossary

• SG - Security Group
• VR - Virtual Router
• VM - User Virtual Machine

Requirements

• SG is zone-level flag, if a zone is SG enabled, all networks inside this zone must be SG enabled., if zone is SG disabled, all networks inside this zone must be SG disabled.
• All types of shared networks are supported in SG enabled advanced zone, including zone-wide shared network, account-specific shared network, domain-wide shared network.
• Isolated networks cannot be added to advanced SG enabled zone.
• There can be multiple SG enabled shared network in one advanced SG enabled zone
• User VM can be deployed on multiple SG enabled networks.
• SG is on VM level(not NIC level), if a VM has multiple NICs, SG rule applies to all NICs.
• SG can cross multiple networks, VMs on different networks can be in one SG.
• Only one network service provider is supported in advanced SG enabled zone - Virtual Router
• support KVM  and XenServer hypervisor.
• Don't support Vmware, OVM, etc. hypervisor
• SG functionality is as same as in Basic zone in terms of Ingress/Egress rules behavior

• No Isolated networks can be added to the Advance SG enabled zone. No Shared Domain wide networks are allowed either.
• If VM is deployed in SG enabled Shared network, it can't have more than 1 Nic - can't belong to any other network.

• When Advance zone is Security Group enabled ("securitygroupenabled=true" is passed to createZone API call; corresponding field is being set to true in the DB), only one Shared Zone Wide SG Enabled Guest network can be added to this zone +  any number of Shared Account Specific SG Disabled networks.
• Shared Zone Wide SG Enabled Guest network is required  in Advance SG enabled zone as CPVM/SSVM are using it.
• User vm can be deployed either in Shared Zone Wide SG enabled network, or in 1-n Shared Account Specific networks. Combination of SG enabled and SG disabled networks for the same VM is not supported.

Feature specification

Code changes

As the 2.2.x code was never removed, we just have to make sure it works + put some additional limitations/fixes to the API related to the 3.0.x changes to NaaS (there was no notion of Physical network/Traffic types in 2.2.x; plus in 2.2.x Shared Zone wide network was created automatically as a part of addZone call.

Things to check:

Make sure that all 2.2.x limitations for Advance SG zone, are still respected in the code. And fix if something got broken/disabled along the way.

3.0.x fixes

Add Zone flow

Don't create Guest network automatically as a part of addZone

Add Traffic Type flow

Don't allow adding Public Traffic Type to the SG enabled Advance zone.

Create Guest Network flow

1) Only Shared Zone wide and Account specific networks can be added to the SG enabled Advance zone.

2) Don't allow to add more than 1 Shared Zone wide network to the zone. This network has to:

• Have VR as the provider for all its services
• SG Service should be mandatory

System vms (CPVM/SSVM) will have a NIC in the Shared SG network, so before the network is added, the system is not ready for user vm launch.

3) Only VR can be a provider for all the services

Client API changes

• Add "securitygroupenabled" (boolean/optional) to the listZones request.

DB modifications

No DB modifications are needed

UI

The flows below require changes:

Add Zone

• Add check box "Enable Security Group" to the first page of create Zone dialog. If Security Group selected, pass
  securitygroupenabled=true to the addZone api call.
• When create physical network(s) on the next page, show L3(security groups) isolation option as a choice only when "Enable SecurityGroup" was checked when create the zone. And show it only for one of the physical networks as we allow to have only one Shared SG enabled network in the zone at this point.
• Add an ability to select multiple Isolation methods at the same time (Vlan, L3, GRE). Pass it as a coma separated list to createPhysicalNetwork call (API already supports it)
• Like in Basic zone, we should force admin to create Guest Network as a part of zone creation. With the only 2 differences - Vlan field is required; and network offering should be SG enabled.
• No Public traffic type support when add SG Advance zone
• Allow having multiple physical networks though.
• When add first cluster/host, show KVM as the only one available hypervisor.

Add Cluster

• Only allow adding KVM cluster to Advance SG enabled zone

Infrastructure -> PhysicalNetworks Diagram -> Modify Guest traffic type->AddNetwork

• Only allow adding Shared Account specific networks (SG disabled) when the zone is Advance SG enabled
• If there are no Shared Zone wide SG enabled network in the zone (user created the zone using API and didn't add the network yet); allow to add SG enabled Zone wide shared network.

Networks tab

• Add SecurityGroup to the list of Views (drop box) on the top of the view. Show it only when 1) there is at least 1 Basic zone in the cloudStack 2) There is at least one Advance zone that is SG enabled (execute listZones&securitygroupenabled=true)

Deploy VM flow

• Get all the networks available to the User with a simple listNetworks&account=&domainId&type=Shared API call
• Don't allow user to select combination of SG enabled and disabled network
• When SG enabled network is selected, show Security Group list to select from

Upgrade flow

• When create physical network traffic types, don't create Public traffic type.
• The rest of the upgrade should be handled the same way we handle it for other zones

Future release plans

In the future releases we are going to:

• Add support for multiple SG enabled Shared networks in Advance zone
• Add support for SG in Isolated networks
• Implement SG based Isolation across Shared networks.
• Support for SG enabled Vm to have multiple Nics (being deployed in multiple networks)
• Feature support in VPC networks
• Add support for Xen hypervisor in Advance SG enabled network