disable_convox_resolver

Description

The disable_convox_resolver parameter allows you to disable the Convox resolver and use the Kubernetes resolver instead for DNS resolution within your rack. This parameter is particularly useful when using proxy_protocol=true with internal service routing, as recent nginx version updates require the Kubernetes resolver to function properly in this configuration.

Default Value

The default value for disable_convox_resolver is false, meaning the Convox resolver is enabled by default.

Use Cases

• Proxy Protocol Compatibility: Required when using both proxy_protocol=true and internal service routing to ensure proper functionality.
• Internal Service Communication: Resolves compatibility issues with updated nginx versions when routing between internal services.
• Kubernetes-Native DNS: Allows applications to use the standard Kubernetes DNS resolver for service discovery.
• Troubleshooting DNS Issues: Provides an alternative DNS resolution method when experiencing issues with the Convox resolver.
• Custom DNS Requirements: Enables use of Kubernetes DNS features that may not be available through the Convox resolver.

Setting Parameters

To disable the Convox resolver and use the Kubernetes resolver instead:

$ convox rack params set disable_convox_resolver=true -r rackName
Setting parameters... OK

To re-enable the Convox resolver (default behavior):

$ convox rack params set disable_convox_resolver=false -r rackName
Setting parameters... OK

Common Configuration Pattern

This parameter is specifically required when you need to use both proxy_protocol=true and internal service routing:

$ convox rack params set proxy_protocol=true -r rackName
$ convox rack params set disable_convox_resolver=true -r rackName

Additional Information

• This parameter provides a solution for compatibility issues between the Convox resolver and proxy_protocol=true functionality.
• When disabled, the Convox resolver is replaced with the standard Kubernetes DNS resolver.
• The change affects all services within the rack and how they resolve DNS queries.
• Internal service routing requires the Kubernetes resolver when using proxy protocol with recent nginx versions.
• This setting maintains backward compatibility with existing configurations that do not use proxy protocol.
• The parameter can be toggled at any time without requiring application redeployment, though services may need to restart to pick up the new DNS configuration.

DNS Resolution Behavior

• Convox Resolver (default): Uses Convox's custom DNS resolution system for service discovery and external DNS queries.
• Kubernetes Resolver (when disabled): Uses the standard Kubernetes cluster DNS system, typically CoreDNS, for all DNS resolution.

Troubleshooting

If you experience DNS resolution issues or internal service communication problems, particularly when using proxy protocol, try enabling this parameter:

$ convox rack params set disable_convox_resolver=true -r rackName

Related Parameters

• proxy_protocol: When enabled, requires this parameter to be set to true for proper internal service routing.
• internal_router: May be affected by DNS resolver choice when routing internal traffic.

Version Requirements

This feature requires at least Convox rack version 3.21.4.