Managed Nginx-based HTTP Cache Service
The Nginx-based HTTP caching service is designed to optimize web traffic and enhance web application performance. This service combines custom-built Nginx instances with HAProxy for efficient caching and load balancing.
Deployment information
The Nginx instances include the following modules and features:
- VTS module for statistics
- Integration with ip2location
- Integration with ip2proxy
- Support for 51Degrees
- Cache purge functionality
HAproxy plays a vital role in this setup by directing incoming traffic to specific Nginx instances based on a consistent hash calculated from the URL. Each Nginx instance includes a Persistent Volume Claim (PVC) for storing cached content, ensuring fast and reliable access to frequently used resources.
Deployment Details
The deployment architecture is illustrated in the diagram below:
┌─────────┐
│ metallb │ arp announce
└────┬────┘
│
│
┌───────▼───────────────────────────┐
│ kubernetes service │ node
│ (externalTrafficPolicy: Local) │ level
└──────────┬────────────────────────┘
│
│
┌────▼────┐ ┌─────────┐
│ haproxy │ │ haproxy │ loadbalancer
│ (active)│ │ (backup)│ layer
└────┬────┘ └─────────┘
│
│ balance uri whole
│ hash-type consistent
┌──────┴──────┬──────────────┐
┌───▼───┐ ┌───▼───┐ ┌───▼───┐ caching
│ nginx │ │ nginx │ │ nginx │ layer
└───┬───┘ └───┬───┘ └───┬───┘
│ │ │
┌────┴───────┬─────┴────┬─────────┴──┐
│ │ │ │
┌───▼────┐ ┌────▼───┐ ┌───▼────┐ ┌────▼───┐
│ origin │ │ origin │ │ origin │ │ origin │
└────────┘ └────────┘ └────────┘ └────────┘
Known issues
- VTS module shows wrong upstream response time, github.com/vozlt/nginx-module-vts#198
Parameters
Common parameters
| Name | Description | Type | Value |
|---|---|---|---|
size | Persistent Volume Claim size, available for application data | quantity | 10Gi |
storageClass | StorageClass used to store the data | string | "" |
external | Enable external access from outside the cluster | bool | false |
Application-specific parameters
| Name | Description | Type | Value |
|---|---|---|---|
endpoints | Endpoints configuration, as a list of ip:port | []string | [] |
HAProxy parameters
| Name | Description | Type | Value |
|---|---|---|---|
haproxy | HAProxy configuration | object | {} |
haproxy.replicas | Number of HAProxy replicas | int | 2 |
haproxy.resources | Explicit CPU and memory configuration for each replica. When left empty, the preset defined in resourcesPreset is applied. | object | {} |
haproxy.resources.cpu | CPU available to each replica | *quantity | null |
haproxy.resources.memory | Memory (RAM) available to each replica | *quantity | null |
haproxy.resourcesPreset | Default sizing preset used when resources is omitted. Allowed values: nano, micro, small, medium, large, xlarge, 2xlarge. | string | nano |
Nginx parameters
| Name | Description | Type | Value |
|---|---|---|---|
nginx | Nginx configuration | object | {} |
nginx.replicas | Number of Nginx replicas | int | 2 |
nginx.resources | Explicit CPU and memory configuration for each replica. When left empty, the preset defined in resourcesPreset is applied. | *object | null |
nginx.resources.cpu | CPU available to each replica | *quantity | null |
nginx.resources.memory | Memory (RAM) available to each replica | *quantity | null |
nginx.resourcesPreset | Default sizing preset used when resources is omitted. Allowed values: nano, micro, small, medium, large, xlarge, 2xlarge. | string | nano |
Parameter examples and reference
resources and resourcesPreset
resources sets explicit CPU and memory configurations for each replica.
When left empty, the preset defined in resourcesPreset is applied.
resources:
cpu: 4000m
memory: 4Gi
resourcesPreset sets named CPU and memory configurations for each replica.
This setting is ignored if the corresponding resources value is set.
| Preset name | CPU | memory |
|---|---|---|
nano | 250m | 128Mi |
micro | 500m | 256Mi |
small | 1 | 512Mi |
medium | 1 | 1Gi |
large | 2 | 2Gi |
xlarge | 4 | 4Gi |
2xlarge | 8 | 8Gi |
endpoints
endpoints is a flat list of IP addresses:
endpoints:
- 10.100.3.1:80
- 10.100.3.11:80
- 10.100.3.2:80
- 10.100.3.12:80
- 10.100.3.3:80
- 10.100.3.13:80