* Docs for Unix Domain Sockets
There are a number of cases where a user might wish to either 1)
expose a service through a Unix Domain Socket in the filesystem
('downstream') or 2) connect to an upstream service by a local unix
domain socket (upstream).
As of Consul (1.10-beta2) we've added new syntax and support to configure
the Envoy proxy to support this
To connect to a service via local Unix Domain Socket instead of a
port, add local_bind_socket_path and optionally local_bind_socket_mode
to the upstream config for a service:
upstreams = [
{
destination_name = "service-1"
local_bind_socket_path = "/tmp/socket_service_1"
local_bind_socket_mode = "0700"
...
}
...
]
This will cause Envoy to create a socket with the path and mode
provided, and connect that to service-1
The mode field is optional, and if omitted will use the default mode
for Envoy. This is not applicable for abstract sockets. See
https://www.envoyproxy.io/docs/envoy/latest/api-v3/config/core/v3/address.proto#envoy-v3-api-msg-config-core-v3-pipe
for details
NOTE: These options conflict the local_bind_socket_port and
local_bind_socket_address options. We can bind to an port or we can
bind to a socket, but not both.
To expose a service listening on a Unix Domain socket to the service
mesh use either the 'socket_path' field in the service definition or the
'local_service_socket_path' field in the proxy definition. These
fields are analogous to the 'port' and 'service_port' fields in their
respective locations.
services {
name = "service-2"
socket_path = "/tmp/socket_service_2"
...
}
OR
proxy {
local_service_socket_path = "/tmp/socket_service_2"
...
}
There is no mode field since the service is expected to create the
socket it is listening on, not the Envoy proxy.
Again, the socket_path and local_service_socket_path fields conflict
with address/port and local_service_address/local_service_port
configuration entries.
Set up a simple service mesh with dummy services:
socat -d UNIX-LISTEN:/tmp/downstream.sock,fork UNIX-CONNECT:/tmp/upstream.sock
socat -v tcp-l:4444,fork exec:/bin/cat
services {
name = "sock_forwarder"
id = "sock_forwarder.1"
socket_path = "/tmp/downstream.sock"
connect {
sidecar_service {
proxy {
upstreams = [
{
destination_name = "echo-service"
local_bind_socket_path = "/tmp/upstream.sock"
config {
passive_health_check {
interval = "10s"
max_failures = 42
}
}
}
]
}
}
}
}
services {
name = "echo-service"
port = 4444
connect = { sidecar_service {} }
Kind = "ingress-gateway"
Name = "ingress-service"
Listeners = [
{
Port = 8080
Protocol = "tcp"
Services = [
{
Name = "sock_forwarder"
}
]
}
]
consul agent -dev -enable-script-checks -config-dir=./consul.d
consul connect envoy -sidecar-for sock_forwarder.1
consul connect envoy -sidecar-for echo-service -admin-bind localhost:19001
consul config write ingress-gateway.hcl
consul connect envoy -gateway=ingress -register -service ingress-service -address '{{ GetInterfaceIP "eth0" }}:8888' -admin-bind localhost:19002
netcat 127.0.0.1 4444
netcat 127.0.0.1 8080
Signed-off-by: Mark Anderson <manderson@hashicorp.com>
* fixup Unix capitalization
Signed-off-by: Mark Anderson <manderson@hashicorp.com>
* Update website/content/docs/connect/registration/service-registration.mdx
Co-authored-by: Blake Covarrubias <blake@covarrubi.as>
* Provide examples in hcl and json
Signed-off-by: Mark Anderson <manderson@hashicorp.com>
* Apply suggestions from code review
Co-authored-by: Blake Covarrubias <blake@covarrubi.as>
* One more fixup for docs
Signed-off-by: Mark Anderson <manderson@hashicorp.com>
Co-authored-by: Blake Covarrubias <blake@covarrubi.as>
* website: migrate to new nav-data format
* website: clean up unused intro content
* website: remove deprecated sidebar_title from frontmatter
* website: add react-content to fix global style import issue
Jared Kirschner