docs: adding env var info, resolves #7926

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trujillo-adam 2021-08-09 11:47:26 -07:00
parent e91996f130
commit 3fabe18acd
2 changed files with 56 additions and 46 deletions

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@ -12,17 +12,18 @@ optionally exposing a gRPC service on the local agent that serves [Envoy's xDS
configuration
API](https://www.envoyproxy.io/docs/envoy/v1.17.2/api-docs/xds_protocol).
Consul can configure Envoy sidecars to proxy http/1.1, http2, or gRPC traffic at
L7 or any other tcp-based protocol at L4. Prior to Consul 1.5.0 Envoy proxies
could only proxy tcp at L4.
Consul can configure Envoy sidecars to proxy traffic over the following protocols:
Configuration of some [L7 features](/docs/connect/l7-traffic-management)
is possible via [configuration entries](/docs/agent/config-entries). If
you wish to use an Envoy feature not currently exposed through these config
entries as an interim solution, you can add [custom Envoy
configuration](#advanced-configuration) in the [proxy service
definition](/docs/connect/registration/service-registration) allowing you
to use the more powerful features of Envoy.
| Protocol | Service network support |
| ----------------------- | ----------------------- |
| HTTP/1.1 | L7 |
| HTTP2 | L7 |
| gRPC | L7 |
| All TCP-based protocols | L4 |
On Consul 1.5.0 and older, Envoy proxies can only proxy TCP traffic at L4.
Some [L7 features](/docs/connect/l7-traffic-management) can be configured using [configuration entries](/docs/agent/config-entries). You can add [custom Envoy configurations](#advanced-configuration) to the [proxy service definition](/docs/connect/registration/service-registration) to use Envoy features that are not currently exposed through configuration entries. Adding custom Envoy configurations to the service definition is an interim solution that enables you to use the more powerful features of Envoy.
~> **Note:** When using Envoy with Consul and not using the [`consul connect envoy` command](/commands/connect/envoy)
Envoy must be run with the `--max-obj-name-len` option set to `256` or greater for Envoy versions prior to 1.11.0.
@ -33,25 +34,18 @@ Consul's Envoy support was added in version 1.3.0. The following table shows
compatible Envoy versions.
| Consul Version | Compatible Envoy Versions |
| ------------------- | -------------------------------- |
| ------------------- | ------------------------------------------------------ |
| 1.10.x | 1.18.3, 1.17.3, 1.16.4, 1.15.5 |
| 1.9.x | 1.16.4, 1.15.5, 1.14.7‡, 1.13.7‡ |
| 1.9.x | 1.16.4, 1.15.5, 1.14.7<sup>1</sup>, 1.13.7<sup>1</sup> |
| 1.8.x | 1.14.7, 1.13.7, 1.12.7, 1.11.2 |
| 1.7.x | 1.13.7, 1.12.7, 1.11.2, 1.10.0\* |
| 1.6.x, 1.5.3, 1.5.2 | 1.11.1, 1.10.0, 1.9.1, 1.8.0 |
| 1.5.1, 1.5.0 | 1.9.1, 1.8.0 |
| 1.4.x, 1.3.x | 1.9.1, 1.8.0†, 1.7.0 |
| 1.7.x | 1.13.7, 1.12.7, 1.11.2, 1.10.0<sup>2</sup> |
| 1.6.x, 1.5.3, 1.5.2 | 1.11.1, 1.10.0, 1.9.1, 1.8.0<sup>3</sup> |
| 1.5.1, 1.5.0 | 1.9.1, 1.8.0<sup>3</sup> |
| 1.4.x, 1.3.x | 1.9.1, 1.8.0†, 1.7.0<sup>3</sup> |
~> ‡ To ensure that intention enforcement is updated as quickly as possible
after any changes, it is advised to run Consul 1.9.0+ with Envoy 1.15.0+ due to a
[listener update improvement](https://github.com/envoyproxy/envoy/pull/10662).<br/><br/>
† Envoy versions lower than 1.9.1 are vulnerable to
[CVE-2019-9900](https://github.com/envoyproxy/envoy/issues/6434) and
[CVE-2019-9901](https://github.com/envoyproxy/envoy/issues/6435). Both are
related to HTTP request parsing and so only affect Consul Connect users if they
have configured HTTP routing rules. Still, we recommend that you use the most
recent supported Envoy for your Consul version where possible.<br/><br/> \* Envoy 1.10.0 requires setting
[`-envoy-version`](/commands/connect/envoy#envoy-version) in the `consul connect envoy` command. This was introduced in Consul 1.7.0.
1. Use Consul 1.9.0+ with Envoy 1.15.0+ to ensure that intention enforcement is updated as quickly as possible after any changes. [Additional information](https://github.com/envoyproxy/envoy/pull/10662).
1. Envoy 1.10.0 requires setting [`-envoy-version`](/commands/connect/envoy#envoy-version) in the `consul connect envoy` command. This was introduced in Consul 1.7.0.
1. Envoy 1.9.1 and older are vulnerable to [CVE-2019-9900](https://github.com/envoyproxy/envoy/issues/6434) and [CVE-2019-9901](https://github.com/envoyproxy/envoy/issues/6435). Both issues are related to parsing HTTP requests and only affect Consul Connect users if they have configured HTTP routing rules. We recommend that you use the most recent supported Envoy for your version of Consul when possible.
## Getting Started
@ -61,7 +55,7 @@ Envoy with Connect](https://learn.hashicorp.com/tutorials/consul/service-mesh-wi
## Configuration
Envoy proxies require two types of configuration: an initial _bootstrap
configuration_ and dynamic configuration that is discovered from a "management
configuration_ and a _dynamic configuration_ that is discovered from a "management
server", in this case Consul.
The bootstrap configuration at a minimum needs to configure the proxy with an
@ -93,28 +87,40 @@ responsibility for correctly configuring Envoy and ensuring version support etc.
## Intention Enforcement
[Intentions] are enforced using Envoy's RBAC filters. Depending upon the
configured [protocol] of the proxied service these are either enforced
per-connection (L4) using a network filter or per-request (L7) using an HTTP
[Intentions] are enforced using Envoy's RBAC filters. Depending on the
configured [protocol] of the proxied service, intentions are either enforced
per-connection (L4) using a network filter, or per-request (L7) using an HTTP
filter.
-> **Note:** Prior to Consul 1.9.0 intentions were exclusively enforced
per-connection (L4) using an `ext_authz` network filter.
## Fetching Certificates
Envoy will use the [`CONSUL_HTTP_TOKEN`](/commands#consul_http_token) and [`CONSUL_HTTP_ADDR`](/commands#consul_http_addr) environment variables to contact Consul to fetch certificates if the following conditions are met:
- The `CONSUL_HTTP_TOKEN` environment variable contains a Consul ACL.
- The Consul ACL has the necessary permissions to read configuration for that service.
If TLS is enabled on Consul, you will also need to add the following environment variables _prior_ to starting Envoy:
- [`CONSUL_CACERT`](/commands#consul_cacert)
- [`CONSUL_CLIENT_CERT`](/commands#consul_client_cert)
- [`CONSUL_CLIENT_KEY`](/commands#consul_client_key)
## Bootstrap Configuration
Envoy requires an initial bootstrap configuration file. The easiest way to
create this is using the [`consul connect envoy`
command](/commands/connect/envoy). The command can either output the
bootstrap configuration directly to stdout or can generate it and then `exec`
the Envoy binary as a convenience wrapper.
bootstrap configuration directly to stdout, or generate the configuration and issue an `exec` command
to the Envoy binary as a convenience wrapper.
Because some Envoy configuration options like metrics and tracing sinks can only be
Because some Envoy configuration options, such as metrics and tracing sinks, can only be
specified via the bootstrap configuration, Connect as of Consul 1.5.0 adds
the ability to control some parts of the bootstrap config via proxy
configuration options.
the ability to control some parts of the bootstrap config via proxy configuration options.
Users can add the following configuration items to the [global `proxy-defaults`
Add the following configuration items to the [global `proxy-defaults`
configuration entry](/docs/connect/config-entries/proxy-defaults) or override them directly in the `proxy.config` field
of a [proxy service
definition](/docs/connect/registration/service-registration) or
@ -168,9 +174,7 @@ definition](/docs/connect/registration/service-registration) or
- `envoy_stats_flush_interval` - Configures Envoy's
[`stats_flush_interval`](https://www.envoyproxy.io/docs/envoy/v1.17.2/api-v3/config/bootstrap/v3/bootstrap.proto#envoy-v3-api-field-config-bootstrap-v3-bootstrap-stats-flush-interval).
There are more possibilities available in the [Advanced
Configuration](#advanced-configuration) section that allow incremental or
complete control over the bootstrap configuration generated.
The [Advanced Configuration](#advanced-configuration) section describes additional configurations that allow incremental or complete control over the bootstrap configuration generated.
## Dynamic Configuration

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@ -206,7 +206,7 @@ entries](/docs/connect/config-entries/service-resolver) are intended to replace
Prepared Queries in Consul entirely, but for now these are still used in some
configurations.
## Sidecar instantiation
## Sidecar Instantiation
Consul does not start or manage sidecar proxies processes. Proxies running on a
physical host or VM are designed to be started and run by process supervisor
@ -218,10 +218,16 @@ The proxy will use the [`CONSUL_HTTP_TOKEN`](/commands#consul_http_token) and
[`CONSUL_HTTP_ADDR`](/commands#consul_http_addr) environment variables to
contact Consul to fetch certificates, provided the `CONSUL_HTTP_TOKEN`
environment variable contains a Consul ACL that has the necessary permissions
to read configuration for that service. If you use our Go [`api` package] then
to read configuration for that service. If you use our Go [`api` package], then
those environment variables will be read and the client configured for you
automatically.
If TLS is enabled on Consul, you will also need to add the following environment variables _prior_ to starting the proxy:
- [`CONSUL_CACERT`](/commands#consul_cacert)
- [`CONSUL_CLIENT_CERT`](/commands#consul_client_cert)
- [`CONSUL_CLIENT_KEY`](/commands#consul_client_key)
The ID of the proxy service comes from the user. See [`consul connect envoy`](/commands/connect/envoy) as an example. You may start it with the
`-proxy-id` flag and pass the ID of the proxy service you registered elsewhere.
A nicer UX is available for end-users using the `-sidecar-for=<service>`