attractor.md

Attractor

The Attractor defines a group of Front-Ends (FEs) sharing commonalities, for example; external interface to utilize, IP-address assignment method, gateway(s) to establish connection with, VIP-addresses to announce etc.

This resource must be created with label metadata.labels.trench to specify its owner reference trench.

API

• v1
• v1alpha1 (deprecated)

Types

TODO

nsm-vlan

TODO

vlan-id 1 to 4094

TODO

The data plane of this type of attractor depends on the NSM version. This is documented here:

• NSM v1.7.0 to latest
• NSM v1.1.0 to v1.6.1

Here is an example of an Attractor object with nsm-vlan 1 to 4094:

apiVersion: meridio.nordix.org/v1alpha1
kind: Attractor
metadata:
  name: attractor-a-1
  labels:
    trench: trench-a
spec:
  replicas: 2
  composites:
  - conduit-a-1
  gateways:
  - gateway-v4-a-1
  - gateway-v6-a-1
  vips:
  - vip-a-1-v4
  - vip-a-1-v6
  interface:
    name: ext-vlan0
    ipv4-prefix: 169.254.100.0/24
    ipv6-prefix: 100:100::/64
    type: nsm-vlan
    nsm-vlan:
      vlan-id: 100
      base-interface: eth0

vlan-id 0

In case the base interface needs to be used without adding any additional vlan tagging, the vlan ID property (.spec.interface.nsm-vlan.vlan-id) can be set to 0. This approach may be useful in environments that use vlan in the underlay to provide interfaces for the worker-nodes.

The data plane of this type of attractor depends on the NSM version. This is documented here:

• NSM v1.7.0 to latest
• NSM v1.4.0 to v1.6.1

Here is an example of an Attractor object with nsm-vlan 0:

apiVersion: meridio.nordix.org/v1alpha1
kind: Attractor
metadata:
  name: attractor-a-1
  labels:
    trench: trench-a
spec:
  replicas: 2
  composites:
  - conduit-a-1
  gateways:
  - gateway-v4-a-1
  - gateway-v6-a-1
  vips:
  - vip-a-1-v4
  - vip-a-1-v6
  interface:
    name: ext-vlan0
    ipv4-prefix: 169.254.100.0/24
    ipv6-prefix: 100:100::/64
    type: nsm-vlan
    nsm-vlan:
      vlan-id: 0
      base-interface: eth0

Deployment

After deploying the example from the previous section, the following resources have been created in Kubernetes:

$ kubectl get attractors
NAME            INTERFACE-NAME   INTERFACE-TYPE   GATEWAYS                              VIPS                          COMPOSITES        REPLICAS   TRENCH
attractor-a-1   ext-vlan0        nsm-vlan         ["gateway-a-1-v4","gateway-a-1-v6"]   ["vip-a-1-v4","vip-a-1-v6"]   ["conduit-a-1"]   2          trench-a

2 deployments:

• nse-vlan-<attractor-name>
• stateless-lb-frontend-<attractor-name>

$ kubectl get deployments
NAME                                  READY   UP-TO-DATE   AVAILABLE   AGE
nse-vlan-attractor-a-1                1/1     1            1           3m2s
stateless-lb-frontend-attractor-a-1   2/2     2            2           3m2s

$ kubectl get pods
NAME                                                  READY   STATUS    RESTARTS   AGE
nse-vlan-attractor-a-1-5cf67947d5-jfg4m               1/1     Running   0          3m2s
stateless-lb-frontend-attractor-a-1-d8db96c8f-p9g29   3/3     Running   0          3m2s
stateless-lb-frontend-attractor-a-1-d8db96c8f-x4zjh   3/3     Running   0          3m2s

A PDB

• pdb-<attractor-name>: Pod disruption budget for the stateless-lb-frontend-attractor-a-1 deployment

$ kubectl get pdb
NAME                MIN AVAILABLE   MAX UNAVAILABLE   ALLOWED DISRUPTIONS   AGE
pdb-attractor-a-1   75%             N/A               0                     13s

The meridio-configuration-<trench-name> configmap has also been configured.

The picture below represents a Kubernetes cluster with Attractor applied and highlighted in red:

network-attachment

TODO

apiVersion: meridio.nordix.org/v1
kind: Attractor
metadata:
  name: attractor-a-1
  labels:
    trench: trench-a
spec:
  replicas: 2
  composites:
  - conduit-a-1
  gateways:
  - gateway-v4-a-1
  - gateway-v6-a-1
  vips:
  - vip-a-1-v4
  - vip-a-1-v6
  interface:
    name: eth-ext
    type: network-attachment
    network-attachments:
      - name: ovs-cni-nad
        namespace: default

apiVersion: "k8s.cni.cncf.io/v1"
kind: NetworkAttachmentDefinition
metadata:
  name: ovs-cni-nad
  namespace: default
spec:
  config: '{
      "cniVersion": "0.4.0",
      "name": "myovsnet",
      "plugins": [
        {
          "type":"ovs",
          "name": "myovs",
          "bridge": "br-meridio",
          "vlan": 100,
          "ipam": {
            "log_file": "/tmp/whereabouts.log",
            "type": "whereabouts",
            "ipRanges": [{
              "range": "169.254.100.0/24",
              "exclude": [
                "169.254.100.150/32"
              ]
            }, {
              "range": "100:100::/64",
              "exclude": [
                "100:100::150/128"
              ]
            }]
          }
        }
      ]
  }'

Deployment

TODO

Limitations

• .metadata.name has a limit of 41 (63 - RESOURCE_NAME_PREFIX - 22) characters.
  • 63: The maximum length for .metadata.name in Kubernetes.
  • RESOURCE_NAME_PREFIX: An environemnt variable in the operator adding a prefix to the resources being deployed.
  • 22: Due to the pods names in the stateless-lb-frontend deployment.
• As described in the data plane documentation, using NSM < v1.7.0, deploying multiple attractors with the same VLAN ID will not work.
• An attractor can serve only 1 conduit with .spec.composites.
• Using nsm-vlan, the based interface (.spec.interface.nsm-vlan.vlan-id) must be configured in the device-selector configuration of the NSM forwarder.
• .spec.interface.* properties are mandatory and immutable.
• .metadata.labels.trench property is mandatory and immutable.

Configuration

TODO: Update

Name	Type	Description	Required	Default
name	string	Name of the Attractor	yes
vips	[]string		yes
gateways	[]string		yes
trench	string	Name of the Trench the Attractor belongs to	yes