Other Blueprints

The previous sections describe how to deploy three Aether blueprints, corresponding to three variants of var/main.yml. This section documents additional blueprints, each defined by a combination of Ansible components:

• A vars/main-blueprint.yml file, checked into the aether-onramp repo, is the "root" of the blueprint specification.

• A hosts.ini file, documented by example, specifies the target servers required by the blueprint.

• A set of Make targets, defined in a submodule and imported into OnRamp's global Makefile, provides commands to install and uninstall the blueprint.

• (Optional) A new aether-blueprint repo defines the Ansible Roles and Playbooks required to deploy a new component.

• (Optional) New Roles, Playbooks, and Templates, checked to existing repos/submodules, customize existing components for integration with the new blueprint. To support blueprint independence, these elements are intentionally kept "narrow", rather than glommed onto an existing element.

• (Optional) Any additional hardware (beyond the Ansible-managed Aether servers) required to support the blueprint.

• A Jenkins job, added to the set of OnRamp integration tests, verifies that the blueprint successfully deploys Aether.

The goal of establishing a well-defined procedure for adding new blueprints to OnRamp is to encourage the community to contribute (and maintain) new Aether configurations and deployment scenarios.[1] The rest of this section documents community-contributed blueprints to-date.

[1]

Not all possible configurations of Aether require a blueprint. There are other ways to add variability, for example, by documenting simple ways to modify an existing blueprint. Disabling core.standalone and selecting an alternative core.values_file are two common examples.

Finally, because some blueprints include features that are not compatible with simple configurations like Quick Start, it is sometimes necessary to install/uninstall Aether using a set of narrow Make targets (e.g., 5gc-upf-install) rather than a single broad target (e.g., aether-5gc-install). Such situations are documented in the following subsections.

Multiple UPFs

The base version of SD-Core includes a single UPF, running in the same Kubernetes namespace as the Core's control plane. This blueprint adds the ability to bring up multiple UPFs (each in a different namespace), and uses ROC to establish the UPF-to-Slice-to-Device bindings required to activate end-to-end user traffic. The resulting deployment is then verified using gNBsim.

The Multi-UPF blueprint includes the following:

• Global vars file vars/main-upf.yml gives the overall blueprint specification.

• Inventory file hosts.ini is identical to that used in the Emulated RAN section. Minimally, SD-Core runs on one server and gNBsim runs on a second server. (The Quick Start deployment, with both SD-Core and gNBsim running in the same server, also works.)

• New make targets, 5gc-upf-install and 5gc-upf-uninstall, to be executed after the standard SD-Core installation. The blueprint also reuses the roc-load target to activate new slices in ROC.

• New Ansible role (upf) added to the 5gc submodule, including a new UPF-specific template (upf-5g-values.yaml).

• New models file (roc-5g-models-upf2.json) added to the roc-load role in the amp submodule. This models file is applied as a patch on top of the base set of ROC models. (Since this blueprint is demonstrated using gNBsim, the assumed base models are given by roc-5g-models.json.)

• Two nightly integration tests that validate the Multi-UPF blueprint can be viewed on Jenkins (assuming you are a registered user): single-server test, two-server test.

To use Multi-UPF, first copy the vars file to main.yml:

$ cd vars
$ cp main-upf.yml main.yml

Then edit hosts.ini and vars/main.yml to match your local target servers, and deploy the base system (as in previous sections):

$ make k8s-install
$ make roc-install
$ make roc-load
$ make 5gc-install
$ make gnbsim-install

You can also optionally install the monitoring subsystem. Note that because main.yml sets core.standalone: "false", any models loaded into ROC are automatically applied to SD-Core.

At this point you are ready to bring up additional UPFs and bind them to specific slices and devices. This involves first editing the upf block in the core section of vars/main.yml:

upf:
   ip_prefix: "192.168.252.0/24"
   iface: "access"
   helm:
       chart_ref: aether/bess-upf
  values_file: "deps/5gc/roles/upf/templates/upf-5g-values.yaml"
  additional_upfs:
      "1":
         ip:
            access: "192.168.252.6/24"
            core:   "192.168.250.6/24"
         ue_ip_pool: "172.248.0.0/16"
      # "2":
      #   ip:
      #      access: "192.168.252.7/24"
      #      core:   "192.168.250.7/24"
      #   ue_ip_pool: "172.247.0.0/16"

As shown above, one additional UPF is enabled (beyond upf-0 that already came up as part of SD-Core), with the spec for yet another UPF commented out. In this example configuration, each UPF is assigned a subnet on the access and core bridges, along with the IP address pool for UEs that the UPF serves. Once done with the edits, launch the new UPF(s) by typing:

$ make 5gc-upf-install

At this point the new UPF(s) will be running (you can verify this using kubectl), but no traffic will be directed to them until UEs are assigned to their IP address pool. Doing so requires loading the appropriate bindings into ROC, which you can do by editing the roc_models line in amp section of vars/main.yml. Comment out the original models file already loaded into ROC, and uncomment the new patch that is to be applied:

amp:
   # roc_models: "deps/amp/roles/roc-load/templates/roc-5g-models.json"
   roc_models: "deps/amp/roles/roc-load/templates/roc-5g-models-upf2.json"

Then run the following to load the patch:

$ make roc-load

At this point you can bring up the Aether GUI and see that a second slice and a second device group have been mapped onto the second UPF.

Now you are ready to run traffic through both UPFs, which because the configuration files identified in the servers block of the gnbsim section of vars/main.yml align with the IMSIs bound to each Device Group (which are bound to each slice, which are in turn bound to each UPF), the emulator sends data through both UPFs. To run the emulation, type:

$ make gnbsim-simulator-run

SD-RAN

This blueprint runs SD-Core and SD-RAN in tandem, with RANSIM emulating various RAN elements. (The OnRamp roadmap includes plans to couple SD-RAN with other virtual and physical RAN elements, but RANSIM is currently the only option.)

The SD-RAN blueprint includes the following:

• Global vars file vars/main-sdran.yml gives the overall blueprint specification.

• Inventory file hosts.ini is identical to that used in the Quick Start deployment, with both SD-RAN and SD-Core co-located on a single server.

• New make targets, aether-sdran-install and aether-sdran-uninstall, to be executed after the standard SD-Core installation.

• A new submodule deps/sdran (corresponding to repo aether-sdran) defines the Ansible Roles and Playbooks required to deploy SD-RAN.

• A nightly integration test that validates the SD-RAN blueprint can be viewed on Jenkins (assuming you are a registered user).

To use SD-RAN, first copy the vars file to main.yml:

$ cd vars
$ cp main-sdran.yml main.yml

Then edit hosts.ini and vars/main.yml to match your local target servers, and deploy the base system (as in previous sections), followed by SD-RAN:

$ make aether-k8s-install
$ make aether-5gc-install
$ make aether-sdran-install

Use kubectl to validate that the SD-RAN workload is running, which should result in output similar to the following:

$ kubectl get pods -n sdran
NAME                             READY   STATUS    RESTARTS   AGE
onos-a1t-68c59fb46-8mnng         2/2     Running   0          3m12s
onos-cli-c7d5b54b4-cddhr         1/1     Running   0          3m12s
onos-config-5786dbc85c-rffv7     3/3     Running   0          3m12s
onos-e2t-5798f554b7-jgv27        2/2     Running   0          3m12s
onos-kpimon-555c9fdb5c-cgl5b     2/2     Running   0          3m12s
onos-topo-6b59c97579-pf5fm       2/2     Running   0          3m12s
onos-uenib-6f65dc66b4-b78zp      2/2     Running   0          3m12s
ran-simulator-5d9465df55-p8b9z   1/1     Running   0          3m12s
sd-ran-consensus-0               1/1     Running   0          3m12s
sd-ran-consensus-1               1/1     Running   0          3m12s
sd-ran-consensus-2               1/1     Running   0          3m12s

Note that the SD-RAN workload includes RANSIM as one of its pods; there is no separate "run simulator" step as is the case with gNBsim. To validate that the emulation ran correctly, query the ONOS CLI as follows:

Check onos-kpimon to see if 6 cells are present:

$ kubectl exec -it deployment/onos-cli -n sdran -- onos kpimon list metrics

Check ran-simulator to see if 10 UEs and 6 cells are present:

$ kubectl exec -it deployment/onos-cli -n sdran -- onos ransim get cells
$ kubectl exec -it deployment/onos-cli -n sdran -- onos ransim get ues

Check onos-topo to see if E2Cell is present:

$ kubectl exec -it deployment/onos-cli-n sdran -- onos topo get entity -v

UERANSIM

This blueprint runs UERANSIM in place of gNBsim, providing a second way to direct workload at SD-Core. Of particular note, UERANSIM runs iperf3, making it possible to measure UPF throughput. (In contrast, gNBsim primarily stresses the Core's Control Plane.)

The UERANSIM blueprint includes the following:

• Global vars file vars/main-ueransim.yml gives the overall blueprint specification.

• Inventory file hosts.ini needs to be modified to identify the server that is to run UERANSIM. Currently, a second server is needed, as UERANSIM and SD-Core cannot be deployed on the same server. As an example, hosts.ini might look like this:

[all]
node1  ansible_host=10.76.28.113 ansible_user=aether ansible_password=aether ansible_sudo_pass=aether
node2  ansible_host=10.76.28.115 ansible_user=aether ansible_password=aether ansible_sudo_pass=aether

[master_nodes]
node1

[ueransim_nodes]
node2

• New make targets, aether-ueransim-install, aether-ueransim-run, and aether-ueransim-uninstall, to be executed after the standard SD-Core installation.

• A new submodule deps/ueransim (corresponding to repo aether-ueransim) defines the Ansible Roles and Playbooks required to deploy UERANSIM. It also contains configuration files for the emulator.

• A nightly integration test that validate the UERANSIM blueprint can be viewed on Jenkins (assuming you are a registered user): two-server test.

To use UERANSIM, first copy the vars file to main.yml:

$ cd vars
$ cp main-ueransim.yml main.yml

Then edit hosts.ini and vars/main.yml to match your local target servers, and deploy the base system (as in previous sections), followed by UERANSIM:

$ make aether-k8s-install
$ make aether-5gc-install
$ make aether-ueransim-install
$ make aether-ueransim-run

The last step actually starts UERANSIM, configured according to the specification given in files custom-gnb.yaml and custom-ue.yaml located in deps/ueransim/config. Make target aether-ueransim-run can be run multiple times, where doing so reflects any recent edits to the config files. More information about UERANSIM can be found on GitHub, including how to set up the config files.

Finally, since the main value of UERANSIM is to measure user plane throughput, you may want to play with the UPF's Quality-of-Service parameters, as defined in deps/5gc/roles/core/templates/sdcore-5g-values.yaml. Specifically, see both the UE-level settings associated with ue-dnn-qos and the slice-level settings associated with slice_rate_limit_config.

Physical eNBs

Aether OnRamp is geared towards 5G, but it does support physical eNBs, including 4G-based versions of both SD-Core and AMP. The 4G blueprint has been demonstrated with SERCOMM's 4G/LTE CBRS Small Cell. The blueprint uses all the same Ansible machinery outlined in earlier sections, but starts with a variant of vars/main.yml customized for running physical 4G radios:

$ cd vars
$ cp main-eNB.yml main.yml

Assuming that starting point, the following outlines the key differences from the 5G case:

• There is a 4G-specific repo, which you can find in deps/4gc.

• The core section of vars/main.yml specifies a 4G-specific values file:

  values_file: "deps/4gc/roles/core/templates/radio-4g-values.yaml"

• The amp section of vars/main.yml specifies that 4G-specific models and dashboards get loaded into the ROC and Monitoring services, respectively:

  roc_models: "deps/amp/roles/roc-load/templates/roc-4g-models.json"

  monitor_dashboard:  "deps/amp/roles/monitor-load/templates/4g-monitor"

• You need to edit two files with details for the 4G SIM cards you use. One is the 4G-specific values file used to configure SD-Core:

  deps/4gc/roles/core/templates/radio-4g-values.yaml

  The other is the 4G-specific Models file used to bootstrap ROC:

  deps/amp/roles/roc-load/templates/radio-4g-models.json

• There are 4G-specific Make targets for SD-Core (e.g., make aether-4gc-install and make aether-4gc-uninstall), but the Make targets for AMP (e.g., make aether-amp-install and make aether-amp-uninstall) work unchanged in both 4G and 5G.

The Quick Start and Emulated RAN (gNBsim) deployments are for 5G only, but revisiting the previous sections—substituting the above for their 5G counterparts—serves as a guide for deploying a 4G blueprint of Aether. Note that the network is configured in exactly the same way for both 4G and 5G. This is because SD-Core's implementation of the UPF is used in both cases.

Enable SR-IOV and DPDK

UPF performance can be improved by enabling SR-IOV and DPDK. This blueprint supports both optimizations, where the former depends on the server NIC(s) being SR-IOV capable. The blueprint includes the following:

• Global vars file vars/main-sriov.yml gives the overall blueprint specification.

• Inventory file hosts.ini is identical to that used throughout this Guide. There are no additional node groups.

• New make targets, 5gc-sriov-install and 5gc-sriov-uninstall, to be executed along with the standard SD-Core installation (see below).

• New Ansible role (sriov) added to the 5gc submodule.

• SRIOV-specific override variables required to configure the core are included in a new template: deps/5gc/roles/core/templates/sdcore-5g-sriov-values.yaml.

• Integration tests require SR-IOV capable servers, and so have not yet been added to Jenkins.

To use SR-IOV and DPDK, first copy the vars file to main.yml:

$ cd vars
$ cp main-sriov.yml main.yml

You will see the main difference in the upf block of the core section:

upf:
  ip_prefix: "192.168.252.0/24"
  iface: "access"
  mode: dpdk                        # Options: af_packet or dpdk
  # If mode set to 'dpdk':
  #    - make sure at least two VF devices are created out of 'data_iface'
  #      and these devices are attached to vfio-pci driver;
  #    - use 'sdcore-5g-sriov-values.yaml' file for 'values_file' (above).

Note the VF device requirement in upf block comments, and be sure that the core block points to the alternative override file:

values_file: "deps/5gc/roles/core/templates/sdcore-5g-sriov-values.yaml"

Deploying this blueprint involves the invoking the following sequence of Make targets:

$ make k8s-install
$ make 5gc-router-install
$ make 5gc-sriov-install
$ make 5gc-core-install

The 5gc-sriov-install step happens after the Kubernetes cluster is installed, but before the Core workload is instantiated on that cluster. The corresponding playbook augments Kubernetes with the required extensions. It has been written to do nothing unless variable core.upf.mode is set to dpdk, where OnRamp now includes the 5gc-sriov-install target as part of its default 5gc-install target.

Guidelines for Blueprints

Blueprints define alternate "on ramps" for using Aether. They are intended to provide users with different starting points, depending on the combination of features they are most interested in. The intent is also that users eventually "own" their own customized blueprint, for example by combining features from more than one of the set distributed with OnRamp. Not all such combinations are valid, and not all valid combinations have been been tested. This is why there is not currently one uber-blueprint that satisfies all requirements.

Users are encourage to contribute new blueprints to the official release, for example by adding one or more new features/capabilities, or possibly by demonstrating how to deploy a different combination of existing features. In addition to meeting the general definition of a blueprint (as introduced in the introduction to this section), we recommend the following guidelines.

• Keep blueprints fairly narrow. One of their main values is to document (in code) how a particular feature is enabled and configured. Introduce new roles to keep playbooks narrow. Introduce new values files to keep each example override file narrow.

• Use Ansible best-practices for defining playbooks. This means using Ansible plugins rather than invoking shell scripts, whenever possible.

• Minimize the number of variables exposed in vars/main-blueprint.yml. Their main purpose is direct how Ansible deploys Aether, and not to configure the individual subsystems of a given deployment. The latter details are best defined in a values override file, which can then be referenced by vars/main-blueprint.yml.