mirror of
https://github.com/VictoriaMetrics/VictoriaMetrics.git
synced 2024-12-24 03:06:48 +01:00
83c87f822a
Signed-off-by: Artem Navoiev <tenmozes@gmail.com>
238 lines
12 KiB
Markdown
238 lines
12 KiB
Markdown
---
|
|
sort: 6
|
|
weight: 6
|
|
title: Design
|
|
menu:
|
|
docs:
|
|
parent: "operator"
|
|
weight: 6
|
|
aliases:
|
|
- /operator/design.html
|
|
---
|
|
|
|
# Design
|
|
|
|
This document describes the design and interaction between the custom resource definitions (CRD) that the Victoria
|
|
Metrics Operator introduces.
|
|
|
|
Operator introduces the following custom resources:
|
|
|
|
* [VMSingle](#vmsingle)
|
|
* [VMCluster](#vmcluster)
|
|
* [VMAgent](#vmagent)
|
|
* [VMAlert](#vmalert)
|
|
* [VMServiceScrape](#vmservicescrape)
|
|
* [VMPodScrape](#vmpodscrape)
|
|
* [VMAlertmanager](#vmalertmanager)
|
|
* [VMAlertmanagerConfig](#vmalertmanagerconfig)
|
|
* [VMRule](#vmrule)
|
|
* [VMProbe](#vmprobe)
|
|
* [VMNodeScrape](#vmodescrape)
|
|
* [VMStaticScrape](#vmstaticscrape)
|
|
* [VMAuth](#vmauth)
|
|
* [VMUser](#vmuser)
|
|
|
|
## VMSingle
|
|
|
|
The `VMSingle` CRD declaratively defines a [single-node VM](https://github.com/VictoriaMetrics/VictoriaMetrics)
|
|
installation to run in a Kubernetes cluster.
|
|
|
|
For each `VMSingle` resource, the Operator deploys a properly configured `Deployment` in the same namespace.
|
|
The VMSingle `Pod`s are configured to mount an empty dir or `PersistentVolumeClaimSpec` for storing data.
|
|
Deployment update strategy set to [recreate](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#recreate-deployment).
|
|
No more than one replica allowed.
|
|
|
|
For each `VMSingle` resource, the Operator adds `Service` and `VMServiceScrape` in the same namespace prefixed with
|
|
name `<VMSingle-name>`.
|
|
|
|
## VMCluster
|
|
|
|
The `VMCluster` CRD defines a [cluster version VM](https://github.com/VictoriaMetrics/VictoriaMetrics/tree/cluster).
|
|
|
|
For each `VMCluster` resource, the Operator creates `VMStorage` as `StatefulSet`, `VMSelect` as `StatefulSet` and `VMInsert`
|
|
as deployment. For `VMStorage` and `VMSelect` headless services are created. `VMInsert` is created as service with clusterIP.
|
|
|
|
There is a strict order for these objects creation and reconciliation:
|
|
1. `VMStorage` is synced - the Operator waits until all its pods are ready;
|
|
2. Then it syncs `VMSelect` with the same manner;
|
|
3. `VMInsert` is the last object to sync.
|
|
|
|
All statefulsets are created with [OnDelete](https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/#on-delete)
|
|
update type. It allows to manually manage the rolling update process for Operator by deleting pods one by one and waiting
|
|
for the ready status.
|
|
|
|
Rolling update process may be configured by the operator env variables.
|
|
The most important is `VM_PODWAITREADYTIMEOUT=80s` - it controls how long to wait for pod's ready status.
|
|
|
|
## VMAgent
|
|
|
|
The `VMAgent` CRD declaratively defines a desired [VMAgent](https://github.com/VictoriaMetrics/VictoriaMetrics/tree/master/app/vmagent)
|
|
setup to run in a Kubernetes cluster.
|
|
|
|
For each `VMAgent` resource Operator deploys a properly configured `Deployment` in the same namespace.
|
|
The VMAgent `Pod`s are configured to mount a `Secret` prefixed with `<VMAgent-name>` containing the configuration
|
|
for VMAgent.
|
|
|
|
For each `VMAgent` resource, the Operator adds `Service` and `VMServiceScrape` in the same namespace prefixed with
|
|
name `<VMAgent-name>`.
|
|
|
|
The CRD specifies which `VMServiceScrape` should be covered by the deployed VMAgent instances based on label selection.
|
|
The Operator then generates a configuration based on the included `VMServiceScrape`s and updates the `Secret` which
|
|
contains the configuration. It continuously does so for all changes that are made to the `VMServiceScrape`s or the
|
|
`VMAgent` resource itself.
|
|
|
|
If no selection of `VMServiceScrape`s is provided - Operator leaves management of the `Secret` to the user,
|
|
so user can set custom configuration while still benefiting from the Operator's capabilities of managing VMAgent setups.
|
|
|
|
## VMAlert
|
|
|
|
The `VMAlert` CRD declaratively defines a desired [VMAlert](https://github.com/VictoriaMetrics/VictoriaMetrics/tree/master/app/vmalert)
|
|
setup to run in a Kubernetes cluster.
|
|
|
|
For each `VMAlert` resource, the Operator deploys a properly configured `Deployment` in the same namespace.
|
|
The VMAlert `Pod`s are configured to mount a list of `Configmaps` prefixed with `<VMAlert-name>-number` containing
|
|
the configuration for alerting rules.
|
|
|
|
For each `VMAlert` resource, the Operator adds `Service` and `VMServiceScrape` in the same namespace prefixed with
|
|
name `<VMAlert-name>`.
|
|
|
|
The CRD specifies which `VMRule`s should be covered by the deployed VMAlert instances based on label selection.
|
|
The Operator then generates a configuration based on the included `VMRule`s and updates the `Configmaps` containing
|
|
the configuration. It continuously does so for all changes that are made to `VMRule`s or to the `VMAlert` resource itself.
|
|
|
|
Alerting rules are filtered by selector `ruleNamespaceSelector` in `VMAlert` CRD definition. For selecting rules from all
|
|
namespaces you must specify it to empty value:
|
|
|
|
```yaml
|
|
spec:
|
|
ruleNamespaceSelector: {}
|
|
```
|
|
|
|
|
|
## VMServiceScrape
|
|
|
|
The `VMServiceScrape` CRD allows to define a dynamic set of services for monitoring. Services
|
|
and scraping configurations can be matched via label selections. This allows an organization to introduce conventions
|
|
for how metrics should be exposed. Following these conventions new services will be discovered automatically without
|
|
need to reconfigure.
|
|
|
|
Monitoring configuration based on `discoveryRole` setting. By default, `endpoints` is used to get objects from kubernetes api.
|
|
Its also possible to use `discoveryRole: service` or `discoveryRole: endpointslices`
|
|
|
|
`Endpoints` objects are essentially lists of IP addresses.
|
|
Typically, `Endpoints` objects are populated by `Service` object. `Service` object discovers `Pod`s by a label
|
|
selector and adds those to the `Endpoints` object.
|
|
|
|
A `Service` may expose one or more service ports backed by a list of one or multiple endpoints pointing to
|
|
specific `Pod`s. The same reflected in the respective `Endpoints` object as well.
|
|
|
|
The `VMServiceScrape` object discovers `Endpoints` objects and configures VMAgent to monitor `Pod`s.
|
|
|
|
The `Endpoints` section of the `VMServiceScrapeSpec` is used to configure which `Endpoints` ports should be scraped.
|
|
For advanced use cases, one may want to monitor ports of backing `Pod`s, which are not a part of the service endpoints.
|
|
Therefore, when specifying an endpoint in the `endpoints` section, they are strictly used.
|
|
|
|
> Note: `endpoints` (lowercase) is the field in the `VMServiceScrape` CRD, while `Endpoints` (capitalized) is the Kubernetes object kind.
|
|
|
|
Both `VMServiceScrape` and discovered targets may belong to any namespace. It is important for cross-namespace monitoring
|
|
use cases, e.g. for meta-monitoring. Using the `serviceScrapeSelector` of the `VMAgentSpec`
|
|
one can restrict the namespaces from which `VMServiceScrape`s are selected from by the respective VMAgent server.
|
|
Using the `namespaceSelector` of the `VMServiceScrape` one can restrict the namespaces from which `Endpoints` can be
|
|
discovered from. To discover targets in all namespaces the `namespaceSelector` has to be empty:
|
|
|
|
```yaml
|
|
spec:
|
|
namespaceSelector: {}
|
|
```
|
|
|
|
## VMPodScrape
|
|
|
|
The `VMPodScrape` CRD allows to declaratively define how a dynamic set of pods should be monitored.
|
|
Use label selections to match pods for scraping. This allows an organization to introduce conventions
|
|
for how metrics should be exposed. Following these conventions new services will be discovered automatically without
|
|
need to reconfigure.
|
|
|
|
A `Pod` is a collection of one or more containers which can expose Prometheus metrics on a number of ports.
|
|
|
|
The `VMPodScrape` object discovers pods and generates the relevant scraping configuration.
|
|
|
|
The `PodMetricsEndpoints` section of the `VMPodScrapeSpec` is used to configure which ports of a pod are going to be
|
|
scraped for metrics and with which parameters.
|
|
|
|
Both `VMPodScrapes` and discovered targets may belong to any namespace. It is important for cross-namespace monitoring
|
|
use cases, e.g. for meta-monitoring. Using the `namespaceSelector` of the `VMPodScrapeSpec` one can restrict the
|
|
namespaces from which `Pods` are discovered from. To discover targets in all namespaces the `namespaceSelector` has to
|
|
be empty:
|
|
|
|
```yaml
|
|
spec:
|
|
namespaceSelector:
|
|
any: true
|
|
```
|
|
|
|
## VMAlertmanager
|
|
|
|
The `VMAlertmanager` CRD declaratively defines a desired Alertmanager setup to run in a Kubernetes cluster.
|
|
It provides options to configure replication and persistent storage.
|
|
|
|
For each `Alertmanager` resource, the Operator deploys a properly configured `StatefulSet` in the same namespace.
|
|
The Alertmanager pods are configured to include a `Secret` called `<alertmanager-name>` which holds the used
|
|
configuration file in the key `alertmanager.yaml`.
|
|
|
|
When there are two or more configured replicas the Operator runs the Alertmanager instances in high availability mode.
|
|
|
|
## VMAlertmanagerConfig
|
|
|
|
The `VMAlertmanagerConfig` provides way to configure `VMAlertmanager` configuration with CRD. It allows to define different configuration parts,
|
|
which will be merged by operator into config. It behaves like other config parts - `VMServiceScrape` and etc.
|
|
|
|
## VMRule
|
|
|
|
The `VMRule` CRD declaratively defines a desired Prometheus rule to be consumed by one or more VMAlert instances.
|
|
|
|
Alerts and recording rules can be saved and applied as YAML files, and dynamically loaded without requiring any restart.
|
|
|
|
|
|
## VMPrometheusConverter
|
|
|
|
By default, the Operator converts and updates existing prometheus-operator API objects:
|
|
|
|
`ServiceMonitor` into `VMServiceScrape`
|
|
`PodMonitor` into `VMPodScrape`
|
|
`PrometheusRule` into `VMRule`
|
|
`Probe` into `VMProbe`
|
|
Removing prometheus-operator API objects wouldn't delete any converted objects. So you can safely migrate or run
|
|
two operators at the same time.
|
|
|
|
|
|
## VMProbe
|
|
|
|
The `VMProbe` CRD provides probing target ability with a prober. The most common prober is [blackbox exporter](https://github.com/prometheus/blackbox_exporter).
|
|
By specifying configuration at CRD, operator generates config for `VMAgent` and syncs it. Its possible to use static targets
|
|
or use standard k8s discovery mechanism with `Ingress`.
|
|
You have to configure blackbox exporter before you can use this feature. The second requirement is `VMAgent` selectors,
|
|
it must match your `VMProbe` by label or namespace selector.
|
|
|
|
## VMNodeScrape
|
|
|
|
The `VMNodeScrape` CRD provides discovery mechanism for scraping metrics kubernetes nodes.
|
|
By specifying configuration at CRD, operator generates config for `VMAgent` and syncs it. Its useful for cadvisor scraping,
|
|
node-exporter or other node-based exporters. `VMAgent` nodeScrapeSelector must match `VMNodeScrape` labels.
|
|
|
|
## VMStaticScrape
|
|
|
|
The `VMStaticScrape` CRD provides mechanism for scraping metrics from static targets, configured by CRD targets.
|
|
By specifying configuration at CRD, operator generates config for `VMAgent` and syncs it. It's useful for external targets management,
|
|
when service-discovery is not available. `VMAgent` staticScrapeSelector must match `VMStaticScrape` labels.
|
|
|
|
## VMAuth
|
|
|
|
The `VMAuth` CRD provides mechanism for exposing application with authorization to outside world or to other applications inside kubernetes cluster.
|
|
For first case, user can configure `ingress` setting at `VMAuth` CRD. For second one, operator will create secret with `username` and `password` at `VMUser` CRD name.
|
|
So it will be possible to access this credentials from any application by targeting corresponding kubernetes secret.
|
|
|
|
## VMUser
|
|
|
|
The `VMUser` CRD describes user configuration, its authentication methods `basic auth` or `Authorization` header. User access permissions, with possible routing information.
|
|
User can define routing target with `static` config, by entering target `url`, or with `CRDRef`, in this case, operator queries kubernetes API, retrieves information about CRD and builds proper url.
|