open-consul/website/source/docs/agent/config_entries.html.md

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---
layout: "docs"
page_title: "Configuration Entry Definitions"
sidebar_current: "docs-agent-cfg_entries"
description: |-
Consul allows storing configuration entries centrally to be used as defaults for configuring other aspects of Consul.
---
# Configuration Entries
Configuration entries can be created to provide cluster-wide defaults for various aspects of Consul. Every configuration
entry has at least two fields: `Kind` and `Name`. Those two fields are used to uniquely identify a configuration entry.
When put into configuration files, configuration entries can be specified as HCL or JSON objects.
Example:
```hcl
Kind = "<supported kind>"
Name = "<name of entry>"
```
The two supported `Kind` configuration entries are detailed below.
## Configuration Entry Kinds
### Proxy Defaults - `proxy-defaults`
Proxy defaults allow for configuring global config defaults across all services for Connect proxy configuration. Currently,
only one global entry is supported.
```hcl
Kind = "proxy-defaults"
Name = "global"
Config {
local_connect_timeout_ms = 1000
handshake_timeout_ms = 10000
}
```
* `Kind` - Must be set to `proxy-defaults`
* `Name` - Must be set to `global`
* `Config` - An arbitrary map of configuration values used by Connect proxies. See
#### Proxy Configuration References
* [Consul's Builtin Proxy](/docs/connect/configuration.html#built-in-proxy-options)
* [Envoy](/docs/connect/proxies/envoy.html#bootstrap-configuration)
### Service Defaults - `service-defaults`
Service defaults control default global values for a service, such as its protocol.
```hcl
Kind = "service-defaults"
Name = "web"
Protocol = "http"
```
* `Kind` - Must be set to `service-defaults`
* `Name` - Set to the name of the service being configured.
* `Protocol` - Sets the protocol of the service. This is used by Connect proxies for things like observability features.
## Managing Configuration Entries
Configuration entries should be managed with the Consul [CLI](/docs/commands/config.html) or [API](/api/config.html). Additionally,
as a convenience for initial cluster bootstrapping, configuration entries can be specified in all of the Consul servers's
[configuration files](/docs/agent/options.html#config_entries_bootstrap)
### Managing Configuration Entries with the CLI
#### Creating or Updating a Configuration Entry
The [`consul config write`](/docs/commands/config/write.html) command is used to create and update configuration entries. This command
will load either a JSON or HCL file holding the configuration entry definition and then will push this configuration to Consul.
Example HCL Configuration File - `proxy-defaults.hcl`:
```hcl
Kind = "proxy-defaults"
Name = "global"
Config {
local_connect_timeout_ms = 1000
handshake_timeout_ms = 10000
}
```
Then to apply this configuration, run:
```bash
$ consul config write proxy-defaults.hcl
```
If you need to make changes to a configuration entry, simple edit that file and then rerun the command.
This command will not output anything unless there is an error in applying the configuration entry.
The `write` command also supports a `-cas` option to enable performing a compare-and-swap operation to
prevent overwriting other unknown modifications.
#### Reading a Configuration Entry
The [`consul config read`](/docs/commands/config/read.html) command is used to read the current value of a configuration entry. The
configuration entry will be displayed in JSON form which is how its transmitted between the CLI client and Consul's HTTP API.
Example:
```bash
$ consul config read -kind service-defaults -name web
{
"Kind": "service-defaults",
"Name": "web",
"Protocol": "http"
}
```
#### Listing Configuration Entries
The [`consul config list`](/docs/commands/config/list.html) command is used to list out all the configuration entries for a
given kind.
Example:
```bash
$ consul config list -kind service-defaults
web
api
db
```
#### Deleting Configuration Entries
The [`consul config delete`](/docs/commands/config/delete.html) command is used to delete an entry by specifying both its
`kind` and `name`.
Example:
```bash
$ consul config delete -kind service-defaults -name web
```
This command will not output anything when the deletion is successful.
### Bootstrapping From A Configuration File
Configuration entries can be bootstrapped by adding them inline to each Consul servers configuration file. When a server
gains leadership, it will attempt to initialize the configuration entries. If a configuration entry does not already exist
outside of the servers configuration, then it will create it. If a configuration entry does exist, that matches both `kind`
and `name`, then the server will do nothing.
## Using Configuration Entries For Service Defaults
When the agent is [configured](/docs/agent/options.html#enable_central_service_config) to enable central service configurations,
it will look for service configuration defaults that match a registering service instance. If it finds any, the agent will merge
those defaults with the service instance configuration. This allows for things like service protocol or proxy configuration to
be defined globally and inherited by any affected service registrations.