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Network Namespace Connectivity

Network Namespace Connectivity Collector​

To collect information about network namespace connectivity, use the NetworkNamespaceConnectivity collector. This collector creates two distinct network namespaces and verifies if TCP and UDP traffic can traverse between them.

Parameters​

In addition to the shared collector properties, the networkNamespaceConnectivity collector accepts the following parameters:

fromCIDR (Required)​

The CIDR to be used on the first network namespace.

toCIDR (Required)​

The CIDR to be used on the second network namespace.

port (Optional)​

The port to use for the UDP and TCP connections. Defaults to 8080.

timeout (Optional)​

The time to wait for the UDP and TCP connections to be established. This parameter is expressed with a string following the Go duration format. Defaults to 5s.

Example Collector Definition​

apiVersion: troubleshoot.sh/v1beta2
kind: SupportBundle
metadata:
  name: namespace-connectivity
spec:
  hostCollectors:
  - networkNamespaceConnectivity:
      collectorName: check-network-connectivity
      fromCIDR: 10.0.0.0/24
      toCIDR: 10.0.1.0/24
      port: 9090
      timeout: 10s

Included Resources​

The results of the NetworkNamespaceConnectivity collector are stored in the host-collectors/system directory of the support bundle.

check-network-connectivity.json​

Example of the resulting JSON file:

{
  "from_cidr": "10.0.0.0/24",
  "to_cidr": "10.0.1.0/24",
  "errors": {
    "from_cidr_creation": "",
    "to_cidr_creation": "",
    "udp_client": "error reading from udp socket: read udp 10.0.0.1:60767->10.0.1.1:8888: i/o timeout",
    "udp_server": "error reading from udp socket: read udp 10.0.1.1:8888: i/o timeout",
    "tcp_client": "error dialing tcp: dial tcp 10.0.1.1:8888: i/o timeout",
    "tcp_server": "error accepting connection: accept tcp 10.0.1.1:8888: i/o timeout"
  },
  "output": {
    "logs": [
      "[2024-11-07T13:29:26Z] creating network namespace \"from\" with cidr \"10.0.0.0/24\"",
      "[2024-11-07T13:29:26Z] network namespace \"from\" address range: \"10.0.0.1\" - \"10.0.0.254\"",
      "[2024-11-07T13:29:26Z] creating interface pair \"from-in\" and \"from-out\"",
      "[2024-11-07T13:29:26Z] attaching interface \"from-in\" to namespace \"from\"",
      "[2024-11-07T13:29:26Z] setting default gateway \"10.0.0.254\" for namespace \"from\"",
      "[2024-11-07T13:29:26Z] creating network namespace \"to\" with cidr \"10.0.1.0/24\"",
      "[2024-11-07T13:29:26Z] network namespace \"to\" address range: \"10.0.1.1\" - \"10.0.1.254\"",
      "[2024-11-07T13:29:26Z] creating interface pair \"to-in\" and \"to-out\"",
      "[2024-11-07T13:29:26Z] attaching interface \"to-in\" to namespace \"to\"",
      "[2024-11-07T13:29:26Z] setting default gateway \"10.0.1.254\" for namespace \"to\"",
      "[2024-11-07T13:29:26Z] starting udp echo server on namespace \"to\"(\"10.0.1.1:8888\")",
      "[2024-11-07T13:29:26Z] starting tcp echo server on namespace \"to\"(\"10.0.1.1:8888\")",
      "[2024-11-07T13:29:26Z] reaching to \"10.0.1.1\" from \"10.0.0.1\" with udp",
      "[2024-11-07T13:29:31Z] reaching to \"10.0.1.1\" from \"10.0.0.1\" with tcp",
      "[2024-11-07T13:29:36Z] network namespace connectivity test finished"
    ]
  },
  "success": false
}

Network Namespace Connectivity Analyzer​

The NetworkNamespaceConnectivity analyzer supports two outcomes, one for pass and one for fail. An example is provided below.

Message Templating​

To make the outcome message more informative, you can include certain values gathered by the NetworkNamespaceConnectivity collector as templates. The templates are enclosed in double curly braces with a dot separator. The following templates are available:

TemplateDescription
{{ .ErrorMessage }}Show all error messages found during the collection
{{ .FromCIDR }}The CIDR provided in the collector fromCIDR property
{{ .ToCIDR }}The CIDR provided in the collector toCIDR property

Example Analyzer Definition​

apiVersion: troubleshoot.sh/v1beta2
kind: SupportBundle
metadata:
  name: namespace-connectivity
spec:
  hostCollectors:
  - networkNamespaceConnectivity:
      collectorName: check-network-connectivity
      fromCIDR: 10.0.0.0/24
      toCIDR: 10.0.1.0/24
      port: 9090
      timeout: 10s
  hostAnalyzers:
  - networkNamespaceConnectivity:
      collectorName: check-network-connectivity
      outcomes:
      - pass:
          message: "Communication between {{ .FromCIDR }} and {{ .ToCIDR }} is working"
      - fail:
          message: "{{ .ErrorMessage }}"