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change capitalization of daemon name

pull/26201/head
Karen Bradshaw 2021-01-22 11:39:10 -05:00
parent b0ec53eb74
commit a09fc68df4
1 changed files with 27 additions and 27 deletions
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content/en/docs/tasks/debug-application-cluster/monitor-node-health.md
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@ -8,14 +8,14 @@ reviewers:
<!-- overview -->
*Node problem detector* is a daemon for monitoring and reporting about a node's health.
You can run node problem detector as a `DaemonSet`
or as a standalone daemon. Node problem detector collects information about node problems from various daemons
*Node Problem Detector* is a daemon for monitoring and reporting about a node's health.
You can run Node Problem Detector as a `DaemonSet` or as a standalone daemon.
Node Problem Detector collects information about node problems from various daemons
and reports these conditions to the API server as [NodeCondition](/docs/concepts/architecture/nodes/#condition)
and [Event](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#event-v1-core).
To learn how to install and use the node problem detector, see the
[Node problem detector project documentation](https://github.com/kubernetes/node-problem-detector).
To learn how to install and use Node Problem Detector, see
[Node Problem Detector project documentation](https://github.com/kubernetes/node-problem-detector).
## {{% heading "prerequisites" %}}
@ -25,24 +25,24 @@ To learn how to install and use the node problem detector, see the
## Limitations
* Node problem detector only supports file based kernel log.
* Node Problem Detector only supports file based kernel log.
Log tools such as `journald` are not supported.
* Node problem detector uses the kernel log format for reporting kernel issues.
* Node Problem Detector uses the kernel log format for reporting kernel issues.
To learn how to extend the kernel log format, see [Add support for another log format](#support-other-log-format).
## Enabling node problem detector
## Enabling Node Problem Detector
Some cloud providers enable node problem detector as an {{< glossary_tooltip text="Addon" term_id="addons" >}}.
You can also enable node problem detector with `kubectl` or by creating an Addon pod.
Some cloud providers enable Node Problem Detector as an {{< glossary_tooltip text="Addon" term_id="addons" >}}.
You can also enable Node Problem Detector with `kubectl` or by creating an Addon pod.
### Using kubectl to enable node problem detector {#using-kubectl}
### Using kubectl to enable Node Problem Detector {#using-kubectl}
`kubectl` provides the most flexible management of node problem detector.
`kubectl` provides the most flexible management of Node Problem Detector.
You can overwrite the default configuration to fit it into your environment or
to detect customized node problems. For example:
1. Create a node problem detector configuration similar to `node-problem-detector.yaml`:
1. Create a Node Problem Detector configuration similar to `node-problem-detector.yaml`:
{{< codenew file="debug/node-problem-detector.yaml" >}}
@ -56,7 +56,7 @@ to detect customized node problems. For example:
kubectl apply -f https://k8s.io/examples/debug/node-problem-detector.yaml
```
### Using an Addon pod to enable node problem detector {#using-addon-pod}
### Using an Addon pod to enable Node Problem Detector {#using-addon-pod}
If you are using a custom cluster bootstrap solution and don't need
to overwrite the default configuration, you can leverage the Addon pod to
@ -68,7 +68,7 @@ directory `/etc/kubernetes/addons/node-problem-detector` on a control plane node
## Overwrite the configuration
The [default configuration](https://github.com/kubernetes/node-problem-detector/tree/v0.1/config)
is embedded when building the Docker image of node problem detector.
is embedded when building the Docker image of Node Problem Detector.
However, you can use a [`ConfigMap`](/docs/tasks/configure-pod-container/configure-pod-configmap/)
to overwrite the configuration:
@ -84,7 +84,7 @@ to overwrite the configuration:
{{< codenew file="debug/node-problem-detector-configmap.yaml" >}}
1. Recreate the node problem detector with the new configuration file:
1. Recreate the Node Problem Detector with the new configuration file:
```shell
# If you have a node-problem-detector running, delete before recreating
@ -93,25 +93,25 @@ to overwrite the configuration:
```
{{< note >}}
This approach only applies to a node problem detector started with `kubectl`.
This approach only applies to a Node Problem Detector started with `kubectl`.
{{< /note >}}
Overwriting a configuration is not supported if a node problem detector runs as a cluster Addon.
Overwriting a configuration is not supported if a Node Problem Detector runs as a cluster Addon.
The Addon manager does not support `ConfigMap`.
## Kernel Monitor
*Kernel Monitor* is a system log monitor daemon supported in the node problem detector.
*Kernel Monitor* is a system log monitor daemon supported in the Node Problem Detector.
Kernel monitor watches the kernel log and detects known kernel issues following predefined rules.
The Kernel Monitor matches kernel issues according to a set of predefined rule list in
[`config/kernel-monitor.json`](https://github.com/kubernetes/node-problem-detector/blob/v0.1/config/kernel-monitor.json). The rule list is extensible. You can extend the rule list by overwriting the
[`config/kernel-monitor.json`](https://github.com/kubernetes/node-problem-detector/blob/v0.1/config/kernel-monitor.json). The rule list is extensible. You can expand the rule list by overwriting the
configuration.
### Add new NodeConditions
To support a new `NodeCondition`, you can extend the `conditions` field in
`config/kernel-monitor.json` with a new condition definition such as:
To support a new `NodeCondition`, create a condition definition within the `conditions` field in
`config/kernel-monitor.json`, for example:
```json
{
@ -140,7 +140,7 @@ with a new rule definition:
Check your kernel log path location in your operating system (OS) distribution.
The Linux kernel [log device](https://www.kernel.org/doc/Documentation/ABI/testing/dev-kmsg) is usually presented as `/dev/kmsg`. However, the log path location varies by OS distribution.
The `log` field in `config/kernel-monitor.json` represents the log path inside the container.
You can configure the `log` field to match the device path as seen by the node problem detector.
You can configure the `log` field to match the device path as seen by the Node Problem Detector.
### Add support for another log format {#support-other-log-format}
@ -152,11 +152,11 @@ You can implement a new translator for a new log format.
## Recommendations and restrictions
It is recommended to run the node problem detector in your cluster to monitor node health.
When running the node problem detector, you can expect extra resource overhead on each node.
It is recommended to run the Node Problem Detector in your cluster to monitor node health.
When running the Node Problem Detector, you can expect extra resource overhead on each node.
Usually this is fine, because:
* The kernel log grows relatively slowly.
* A resource limit is set for the node problem detector.
* Even under high load, the resource usage is acceptable. For more information, see the node problem detector
* A resource limit is set for the Node Problem Detector.
* Even under high load, the resource usage is acceptable. For more information, see the Node Problem Detector
[benchmark result](https://github.com/kubernetes/node-problem-detector/issues/2#issuecomment-220255629).