Linux network latency

Linux network latency injects chaos to disrupt network connectivity in linux machine by adding delay to the network requests.

Use cases

• Induces network latency on the target Linux machines.
• Simulates latency in connectivity access by delaying the network requests of the machine.

note

• This fault can be executed on Ubuntu 16 or higher, Debian 10 or higher, CentOS 7 or higher, RHEL 7 or higher, Fedora 30 or higher, and openSUSE LEAP 15.4 or higher.
• The linux-chaos-infrastructure systemd service should be in an active state, and the infrastructure should be in CONNECTED state.

Fault permissions

The fault uses the root Linux user and root user group.

Mandatory tunables

Tunable	Description	Notes
networkInterfaces	Network interfaces to target as comma separated values.	For example: eth0,ens192

Optional tunables

Tunable	Description	Notes
destinationHosts	List of the target host names or keywords. For example: google.com,litmuschaos.io	If neither destinationHosts and destinationIPs is provided, all host names/domains will be targeted
destinationIPs	List of comma-separated target IPs. Supports a list of target destination ports for a given IP, that are separated by a pipe (|). For example, 1.1.1.1,35.24.108.92|3000|8080.	If neither destinationHosts and destinationIPs is provided, all host names/domains will be targeted
latency	Amount of delay added to the connection in ms. For example: 2000	Defaults to 2000
jitter	Amount of jitter to be added in ms. Jitter defines the maximum randomized deviation from the provided latency value. For example: 100	Defaults to 0
sourcePorts	Source ports to be filtered for chaos. For example: 5000,8080 .	Alternatively, the ports can be whitelisted, that is, filtered to be exempt from chaos. Prepend a ! to the list of ports to be exempted. For example, !5000,8080 .
destinationPorts	Destination ports to be filtered for chaos. For example, 5000,8080 .	Alternatively, the ports that can be whitelisted, that is, filtered to be exempt from chaos. Prepend a ! to the list of ports to be exempted. For example, !5000,8080 .
whitelistSSH	Specifies whether the SSH connectivity should be retained during the chaos in the target machine.	Default: true. Supports one of: true, false
duration	Duration through which chaos is injected into the target resource. Should be provided in [numeric-hours]h[numeric-minutes]m[numeric-seconds]s format.	Default: 30s. Examples: 1m25s, 1h3m2s, 1h3s
rampTime	Period to wait before and after injecting chaos. Should be provided in [numeric-hours]h[numeric-minutes]m[numeric-seconds]s format.	Default: 0s. Examples: 1m25s, 1h3m2s, 1h3s

Destination hosts

The destinationHosts input variable subjects the comma-separated names of the target hosts to chaos.

The following YAML snippet illustrates the use of this input variable:

apiVersion: litmuchaos.io/v1alpha1
kind: LinuxFault
metadata:
  name: linux-network-latency
  labels:
    name: network-latency
spec:
  networkChaos/inputs:
    destinationHosts: 'google.com'
    networkInterfaces: "eth0"

Destination IPs

The destinationIPs input variable subjects the comma-separated names of the target IPs to chaos. You can specify the ports to be targeted for an IP by using a pipe (|) as a separator. While providing ports is optional, omitting them will affect all the ports associated with the destination IPs.

The following YAML snippet illustrates the use of this input variable:

apiVersion: litmuchaos.io/v1alpha1
kind: LinuxFault
metadata:
  name: linux-network-latency
  labels:
    name: network-latency
spec:
  networkChaos/inputs:
    destinationIPs: '1.1.1.1,192.168.5.6|80|8080'
    networkInterfaces: "eth0"

Latency and jitter

The latency and jitter input variables add delay and a small deviation to the delay, respectively, with respect to the connection.

The following YAML snippet illustrates the use of this input variable:

apiVersion: litmuchaos.io/v1alpha1
kind: LinuxFault
metadata:
  name: linux-network-latency
  labels:
    name: network-latency
spec:
  networkChaos/inputs:
    latency: "1000"
    jitter: "200"
    networkInterfaces: "eth0"