F5 IPAM Controller [ PREVIEW ]
The F5 IPAM Controller is a Docker container that runs in an orchestration environment and interfaces with an IPAM system.
It allocates IP addresses from an IPAM system’s address pool for hostnames in an orchestration environment.
The F5 IPAM Controller watches orchestration-specific resources and consumes the hostnames within each resource.
In this Preview
The F5 IPAM Controller can allocate IP address from static IP address pool based on the CIDR mentioned in a Kubernetes resource The idea here is that we will support CRD, Type LB and probably also in the future route/ingress. We should make it more generic so that we don't have to update this later, F5 IPAM Controller decides to allocate the IP from the respective IP address pool for the hostname specified in the virtualserver custom resource.
F5 IPAM Deploy Configuration Options
Deployment Options
PARAMETER |
TYPE |
REQUIRED |
DESCRIPTION |
orchestration |
String |
Required |
The orchestration parameter holds the orchestration environment i.e. Kubernetes. |
ip-range |
String |
Required |
ip-range parameter holds the IP address ranges and from this range, it creates a pool of IP address range which gets allocated to the corresponding hostname in the virtual server CRD |
log-level |
String |
Optional |
Log level parameter specify various logging level such as DEBUG, INFO, WARNING, ERROR, CRITICAL. |
Note: On how to configure these Configuration Options, please refer to IPAM Deployment YAML example in below.
RBAC - ServiceAccount, ClusterRole and ClusterRoleBindings for F5 IPAM Controller
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: ipam-ctlr-clusterrole
rules:
- apiGroups: ["fic.f5.com"]
resources: ["f5ipams"]
verbs: ["get", "list", "watch", "update", "patch"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: ipam-ctlr-clusterrole-binding
namespace: kube-system
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: ipam-ctlr-clusterrole
subjects:
- apiGroup: ""
kind: ServiceAccount
name: ipam-ctlr
namespace: kube-system
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: ipam-ctlr
namespace: kube-system
Example: F5 IPAM Controller Deployment YAML
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
name: f5-ipam-controller
name: f5-ipam-controller
namespace: kube-system
spec:
replicas: 1
selector:
matchLabels:
app: f5-ipam-controller
template:
metadata:
labels:
app: f5-ipam-controller
spec:
containers:
- args:
- --orchestration=kubernetes
- --ip-range="10.192.75.111/24-10.192.75.115/24"
- --log-level=DEBUG
command:
- /app/bin/f5-ipam-controller
image: f5devcentral/f5-ipam-controller
imagePullPolicy: IfNotPresent
name: f5-ipam-controller
serviceAccount: ipam-ctlr
serviceAccountName: ipam-ctlr
Deploying RBAC and F5 IPAM Controller
Using kubectl let's apply the above defined RBAC and Deployment definitions.
kubectl create -f f5-ipam-rbac.yaml
kubectl create -f f5-ipam-deployment.yaml
Configuring CIS to work with F5 IPAM Controller
To configure CIS to work with the F5 IPAM controller, the user needs to give a parameter --ipam=true
in the CIS deployment and also provide a parameter cidr
in the virtual server CRD.
Examples
Virtual Server CRD
apiVersion: "cis.f5.com/v1"
kind: VirtualServer
metadata:
name: coffee-virtual-server
labels:
f5cr: "true"
spec:
host: coffee.example.com
cidr: "10.192.75.111/24"
pools:
- path: /coffee
service: svc-2
servicePort: 80
CIS Deployment with ipam enabled
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: k8s-bigip-ctlr-deployment
namespace: kube-system
spec:
replicas: 1
template:
metadata:
name: k8s-bigip-ctlr
labels:
app: k8s-bigip-ctlr
spec:
serviceAccountName: bigip-ctlr
containers:
- name: k8s-bigip-ctlr
image: "f5networks/k8s-bigip-ctlr"
command: ["/app/bin/k8s-bigip-ctlr"]
args: [
"--bigip-username=$(BIGIP_USERNAME)",
"--bigip-password=$(BIGIP_PASSWORD)",
"--bigip-url=<ip_address-or-hostname>",
"--bigip-partition=<name_of_partition>",
"--pool-member-type=nodeport",
"--agent=as3",
"--ipam=true", //Enable IPAM
]
imagePullSecrets:
- name: f5-docker-images
- name: bigip-login
- NOTE: If the user provides the parameter
--ipam=true
in the CIS deployment then it is mandatory to provide the CIDR parameter in virtualserver CRD and also the virtualserver CRD should not have virtualServerAddress parameter.
Updating the Status in Virtual Server CRD
The main aim of IPAM is to provide an IP address corresponding to each hostname provided in the VS CRD.
The user needs to mandatorily provide the host and CIDR in the hostSpecs section of F5-CR. The F5 IPAM Controller, in turn, reads the hostSpecs of CR, processes it, and updates the IPStatus with each host provided in the hostSpecs with host, IP(which is generated from the range of IP address by FIC), and corresponding CIDR.
- F5-ipam-controller (FIC) acts as a communication channel for updating the host, IP, and CIDR in VS CRD.
Below is the example:
apiVersion: "fic.f5.com/v1"
kind: F5IPAM
metadata:
name: f5ipam.sample
namespace: kube-system
spec:
hostSpecs:
- host: cafe.example.com
cidr: 10.192.75.111/24
- host: tea.example.com
cidr: 10.192.75.111/24
status:
IPStatus:
- host: cafe.example.com
ip: 10.192.75.112
cidr: 10.192.75.111/24
- host: tea.example.com
ip: 10.192.75.114
cidr: 10.192.75.111/24
Limitations
- F5-ipam-controller cannot update and delete the hostname in the F5-IPAM custom resource hence update and deletion of IP address for virtual server custom may not work as expected. In case if the user wants to reflect the changes, the user can delete the F5-IPAM custom resource from kube-system named "f5ipam" and restart both the controller.
- Currently, F5 IPAM Controller does not support the update of CIDR and hostname.
- If F5-IPAM Controller is misconfigured after it allocates few IPs for VS CR. It will remove all its entry from the IPStatus. After the user reconfigured with the correct one, FIC may not get the previous same IPs for the hostname
--ip-range
parameter will be improved to accept IP address range from a subnet, range of multiple subnets and range of IP addresses separated by a dash '-'.