VMware Windows network latency

VMware Windows network latency simulates a network latency scenario on Windows OS based VMware VM. It checks the performance of the application running on the VMware Windows VMs under network latency conditions.

Use cases

VMware Windows network latency:

• Determines the resilience of an application when a network latency scenario is simulated on a VMware Windows virtual machine.
• Simulates the situation of network latency for processes running on the application, which degrades their performance.
• Helps verify the application's ability to handle network failures and its failover mechanisms.

Prerequisites

• Kubernetes > 1.16 is required to execute this fault.

• Execution plane should be connected to vCenter and host vCenter on port 443.

• VMware tool should be installed on the target VM with remote execution enabled.

• Adequate vCenter permissions should be provided to access the hosts and the VMs.

• The VM should be in a healthy state before and after injecting chaos.

• Kubernetes secret has to be created that has the vCenter credentials in the CHAOS_NAMESPACE.

• Verify clumsy is installed on the VM, as it's essential for this experiment.

• Run the fault with a user possessing admin rights, preferably the built-in Administrator, to guarantee permissions for memory stress testing. See how to enable the built-in Administrator in Windows.

• VM credentials can be passed as secrets or as a chaos engine environment variable.

apiVersion: v1
kind: Secret
metadata:
  name: vcenter-secret
  namespace: litmus
type: Opaque
stringData:
    VCENTERSERVER: XXXXXXXXXXX
    VCENTERUSER: XXXXXXXXXXXXX
    VCENTERPASS: XXXXXXXXXXXXX

Mandatory tunables

Tunable	Description	Notes
VM_NAME	Name of the target VM(s).	Multiple comma-separated names can be provided. For example, vm-1,vm-2.
VM_USER_NAME	Username of the target VM.	For example, vm-user.
VM_PASSWORD	User password for the target VM.	For example, 1234. Note: You can take the password from secret as well.

Optional tunables

Tunable	Description	Notes
DESTINATION_HOSTS	Comma-separated list of destination hosts to induce latency.	For example, github.com,harness.io. For more information, go to destination hosts.
DESTINATION_IPS	Comma-separated list of destination IPs to induce latency.	For example, 10.0.0.1,10.0.0.2. For more information, go to destination IPs.
NETWORK_LATENCY	The amount of latency to induce (in ms).	Default: 2000. For more information, go to network latency.
PATH_OF_CLUMSY	Path of the Clumsy tool in the VM.	For example, C:\Program Files\Clumsy\. For more information, go to path of Clumsy.
TOTAL_CHAOS_DURATION	Duration that you specify, through which chaos is injected into the target resource (in seconds).	Default: 60 s. For more information, go to duration of the chaos.
RAMP_TIME	Period to wait before and after injecting chaos (in seconds).	Default: 0 s. For more information, go to ramp time.
SEQUENCE	Sequence of chaos execution for multiple instances.	Default: parallel. Supports serial and parallel sequence. For more information, go to sequence of chaos execution.
DEFAULT_HEALTH_CHECK	Determines if you wish to run the default health check which is present inside the fault.	Default: 'true'. For more information, go to default health check.

Destination hosts

The DESTINATION_HOSTS environment variable specifies the destination hosts to induce latency on the target Windows VM.

Use the following example to specify destination hosts:

apiVersion: litmuschaos.io/v1alpha1
kind: ChaosEngine
metadata:
  name: engine-nginx
spec:
  engineState: "active"
  chaosServiceAccount: litmus-admin
  experiments:
  - name: vmware-windows-network-latency
    spec:
      components:
        env:
        # Name of the VM
        - name: VM_NAME
          value: 'test-vm-01'
       # Destination hosts to induce latency
        - name: DESTINATION_HOSTS
          value: 'github.com'

Destination IPs

The DESTINATION_IPS environment variable specifies the destination IPs to induce latency on the target Windows VM.

Use the following example to specify destination IPs:

apiVersion: litmuschaos.io/v1alpha1
kind: ChaosEngine
metadata:
  name: engine-nginx
spec:
  engineState: "active"
  chaosServiceAccount: litmus-admin
  experiments:
  - name: vmware-windows-network-latency
    spec:
      components:
        env:
        # Name of the VM
        - name: VM_NAME
          value: 'test-vm-01'
       # Destination IPs to induce latency
        - name: DESTINATION_IPS
          value: '10.0.0.1,10.0.0.2'

Network latency

The NETWORK_LATENCY environment variable specifies the amount of latency to induce (in ms).

Use the following example to specify network latency:

apiVersion: litmuschaos.io/v1alpha1
kind: ChaosEngine
metadata:
  name: engine-nginx
spec:
  engineState: "active"
  chaosServiceAccount: litmus-admin
  experiments:
  - name: vmware-windows-network-latency
    spec:
      components:
        env:
        # Name of the VM
        - name: VM_NAME
          value: 'test-vm-01'
       # The amount of latency to induce (in ms)
        - name: NETWORK_LATENCY
          value: '2000'

Path of Clumsy

The PATH_OF_CLUMSY environment variable specifies the path of the Clumsy tool in the VM.

Use the following example to specify the path of Clumsy:

apiVersion: litmuschaos.io/v1alpha1
kind: ChaosEngine
metadata:
  name: engine-nginx
spec:
  engineState: "active"
  chaosServiceAccount: litmus-admin
  experiments:
  - name: vmware-windows-network-latency
    spec:
      components:
        env:
        # Name of the VM
        - name: VM_NAME
          value: 'test-vm-01'
       # Path of the Clumsy tool in the VM
        - name: PATH_OF_CLUMSY
          value: 'C:\\Program Files\\Clumsy\\'