This PR adds support for specifying checks in services registered to
the built-in nomad service provider.
Currently only HTTP and TCP checks are supported, though more types
could be added later.
This PR introduces the `address` field in the `service` block so that Nomad
or Consul services can be registered with a custom `.Address.` to advertise.
The address can be an IP address or domain name. If the `address` field is
set, the `service.address_mode` must be set in `auto` mode.
This PR implements first-class support for Nomad running Consul
Connect Mesh Gateways. Mesh gateways enable services in the Connect
mesh to make cross-DC connections via gateways, where each datacenter
may not have full node interconnectivity.
Consul docs with more information:
https://www.consul.io/docs/connect/gateways/mesh-gateway
The following group level service block can be used to establish
a Connect mesh gateway.
service {
connect {
gateway {
mesh {
// no configuration
}
}
}
}
Services can make use of a mesh gateway by configuring so in their
upstream blocks, e.g.
service {
connect {
sidecar_service {
proxy {
upstreams {
destination_name = "<service>"
local_bind_port = <port>
datacenter = "<datacenter>"
mesh_gateway {
mode = "<mode>"
}
}
}
}
}
}
Typical use of a mesh gateway is to create a bridge between datacenters.
A mesh gateway should then be configured with a service port that is
mapped from a host_network configured on a WAN interface in Nomad agent
config, e.g.
client {
host_network "public" {
interface = "eth1"
}
}
Create a port mapping in the group.network block for use by the mesh
gateway service from the public host_network, e.g.
network {
mode = "bridge"
port "mesh_wan" {
host_network = "public"
}
}
Use this port label for the service.port of the mesh gateway, e.g.
service {
name = "mesh-gateway"
port = "mesh_wan"
connect {
gateway {
mesh {}
}
}
}
Currently Envoy is the only supported gateway implementation in Consul.
By default Nomad client will run the latest official Envoy docker image
supported by the local Consul agent. The Envoy task can be customized
by setting `meta.connect.gateway_image` in agent config or by setting
the `connect.sidecar_task` block.
Gateways require Consul 1.8.0+, enforced by the Nomad scheduler.
Closes#9446
This PR fixes a bug where Nomad was more restrictive on Ingress Gateway Configuration
Entry definitions than Consul. Before, Nomad would not allow for declaring IGCEs with
http listeners with service name "*", which is a special feature allowable by Consul.
Note: to make http protocol work, a service-default must be defined setting the
protocol to http for each service.
Fixes: #9729
Consul allows specifying the HTTP body to send in a health check. Nomad
uses Consul for health checking so this just plumbs the value through to
where the Consul API is called.
There is no validation that `body` is not used with an incompatible
check method like GET.
This PR adds the common OSS changes for adding support for Consul Namespaces,
which is going to be a Nomad Enterprise feature. There is no new functionality
provided by this changeset and hopefully no new bugs.
Allow for readiness type checks by configuring nomad to ignore warnings
or errors reported by a service check. This allows the deployment to
progress and while Consul handles introducing the sercive into a
resource pool once the check passes.
This PR implements Nomad built-in support for running Consul Connect
terminating gateways. Such a gateway can be used by services running
inside the service mesh to access "legacy" services running outside
the service mesh while still making use of Consul's service identity
based networking and ACL policies.
https://www.consul.io/docs/connect/gateways/terminating-gateway
These gateways are declared as part of a task group level service
definition within the connect stanza.
service {
connect {
gateway {
proxy {
// envoy proxy configuration
}
terminating {
// terminating-gateway configuration entry
}
}
}
}
Currently Envoy is the only supported gateway implementation in
Consul. The gateay task can be customized by configuring the
connect.sidecar_task block.
When the gateway.terminating field is set, Nomad will write/update
the Configuration Entry into Consul on job submission. Because CEs
are global in scope and there may be more than one Nomad cluster
communicating with Consul, there is an assumption that any terminating
gateway defined in Nomad for a particular service will be the same
among Nomad clusters.
Gateways require Consul 1.8.0+, checked by a node constraint.
Closes#9445
Submitting a job with an ingress gateway in host networking mode
with an absent gateway.proxy block would cause the Nomad client
to panic on NPE.
The consul registration bits would assume the proxy stanza was
not nil, but it could be if the user does not supply any manually
configured envoy proxy settings.
Check the proxy field is not nil before using it.
Fixes#9669
Before, upstreams could only be defined using the default datacenter.
Now, the `datacenter` field can be set in a connect upstream definition,
informing consul of the desire for an instance of the upstream service
in the specified datacenter. The field is optional and continues to
default to the local datacenter.
Closes#8964
* consul: advertise cni and multi host interface addresses
* structs: add service/check address_mode validation
* ar/groupservices: fetch networkstatus at hook runtime
* ar/groupservice: nil check network status getter before calling
* consul: comment network status can be nil
This PR fixes a long standing bug where submitting jobs with changes
to connect services would not trigger updates as expected. Previously,
service blocks were not considered as sources of destructive updates
since they could be synced with consul non-destructively. With Connect,
task group services that have changes to their connect block or to
the service port should be destructive, since the network plumbing of
the alloc is going to need updating.
Fixes#8596#7991
Non-destructive half in #7192
This PR adds initial support for running Consul Connect Ingress Gateways (CIGs) in Nomad. These gateways are declared as part of a task group level service definition within the connect stanza.
```hcl
service {
connect {
gateway {
proxy {
// envoy proxy configuration
}
ingress {
// ingress-gateway configuration entry
}
}
}
}
```
A gateway can be run in `bridge` or `host` networking mode, with the caveat that host networking necessitates manually specifying the Envoy admin listener (which cannot be disabled) via the service port value.
Currently Envoy is the only supported gateway implementation in Consul, and Nomad only supports running Envoy as a gateway using the docker driver.
Aims to address #8294 and tangentially #8647
This change adds the ability to set the fields `success_before_passing` and
`failures_before_critical` on Consul service check definitions. This is a
feature added to Consul v1.7.0 and later.
https://www.consul.io/docs/agent/checks#success-failures-before-passing-critical
Nomad doesn't do much besides pass the fields through to Consul.
Fixes#6913
Before, the service definition for a Connect Native service would always
require setting the `service.task` parameter. Now, that parameter is
automatically inferred when there is only one task in the task group.
Fixes#8274
This PR adds the capability of running Connect Native Tasks on Nomad,
particularly when TLS and ACLs are enabled on Consul.
The `connect` stanza now includes a `native` parameter, which can be
set to the name of task that backs the Connect Native Consul service.
There is a new Client configuration parameter for the `consul` stanza
called `share_ssl`. Like `allow_unauthenticated` the default value is
true, but recommended to be disabled in production environments. When
enabled, the Nomad Client's Consul TLS information is shared with
Connect Native tasks through the normal Consul environment variables.
This does NOT include auth or token information.
If Consul ACLs are enabled, Service Identity Tokens are automatically
and injected into the Connect Native task through the CONSUL_HTTP_TOKEN
environment variable.
Any of the automatically set environment variables can be overridden by
the Connect Native task using the `env` stanza.
Fixes#6083
The field names within the structs representing the Connect proxy
definition were not the same (nomad/structs/ vs api/), causing the
values to be lost in translation for the 'nomad job inspect' command.
Since the field names already shipped in v0.11.0 we cannot simply
fix the names. Instead, use the json struct tag on the structs/ structs
to remap the name to match the publicly expose api/ package on json
encoding.
This means existing jobs from v0.11.0 will continue to work, and
the JSON API for job submission will remain backwards compatible.
Before, if the sidecar_service stanza of a connect enabled service
was missing, the job submission would cause a panic in the nomad
agent. Since the panic was happening in the API handler the agent
itself continued running, but this change will the condition more
gracefully.
By fixing the `Copy` method, the API handler now returns the proper
error.
$ nomad job run foo.nomad
Error submitting job: Unexpected response code: 500 (1 error occurred:
* Task group api validation failed: 2 errors occurred:
* Missing tasks for task group
* Task group service validation failed: 1 error occurred:
* Service[0] count-api validation failed: 1 error occurred:
* Consul Connect must be native or use a sidecar service
Part of #6120
Building on the support for enabling connect proxy paths in #7323, this change
adds the ability to configure the 'service.check.expose' flag on group-level
service check definitions for services that are connect-enabled. This is a slight
deviation from the "magic" that Consul provides. With Consul, the 'expose' flag
exists on the connect.proxy stanza, which will then auto-generate expose paths
for every HTTP and gRPC service check associated with that connect-enabled
service.
A first attempt at providing similar magic for Nomad's Consul Connect integration
followed that pattern exactly, as seen in #7396. However, on reviewing the PR
we realized having the `expose` flag on the proxy stanza inseperably ties together
the automatic path generation with every HTTP/gRPC defined on the service. This
makes sense in Consul's context, because a service definition is reasonably
associated with a single "task". With Nomad's group level service definitions
however, there is a reasonable expectation that a service definition is more
abstractly representative of multiple services within the task group. In this
case, one would want to define checks of that service which concretely make HTTP
or gRPC requests to different underlying tasks. Such a model is not possible
with the course `proxy.expose` flag.
Instead, we now have the flag made available within the check definitions themselves.
By making the expose feature resolute to each check, it is possible to have
some HTTP/gRPC checks which make use of the envoy exposed paths, as well as
some HTTP/gRPC checks which make use of some orthongonal port-mapping to do
checks on some other task (or even some other bound port of the same task)
within the task group.
Given this example,
group "server-group" {
network {
mode = "bridge"
port "forchecks" {
to = -1
}
}
service {
name = "myserver"
port = 2000
connect {
sidecar_service {
}
}
check {
name = "mycheck-myserver"
type = "http"
port = "forchecks"
interval = "3s"
timeout = "2s"
method = "GET"
path = "/classic/responder/health"
expose = true
}
}
}
Nomad will automatically inject (via job endpoint mutator) the
extrapolated expose path configuration, i.e.
expose {
path {
path = "/classic/responder/health"
protocol = "http"
local_path_port = 2000
listener_port = "forchecks"
}
}
Documentation is coming in #7440 (needs updating, doing next)
Modifications to the `countdash` examples in https://github.com/hashicorp/demo-consul-101/pull/6
which will make the examples in the documentation actually runnable.
Will add some e2e tests based on the above when it becomes available.
Enable configuration of HTTP and gRPC endpoints which should be exposed by
the Connect sidecar proxy. This changeset is the first "non-magical" pass
that lays the groundwork for enabling Consul service checks for tasks
running in a network namespace because they are Connect-enabled. The changes
here provide for full configuration of the
connect {
sidecar_service {
proxy {
expose {
paths = [{
path = <exposed endpoint>
protocol = <http or grpc>
local_path_port = <local endpoint port>
listener_port = <inbound mesh port>
}, ... ]
}
}
}
stanza. Everything from `expose` and below is new, and partially implements
the precedent set by Consul:
https://www.consul.io/docs/connect/registration/service-registration.html#expose-paths-configuration-reference
Combined with a task-group level network port-mapping in the form:
port "exposeExample" { to = -1 }
it is now possible to "punch a hole" through the network namespace
to a specific HTTP or gRPC path, with the anticipated use case of creating
Consul checks on Connect enabled services.
A future PR may introduce more automagic behavior, where we can do things like
1) auto-fill the 'expose.path.local_path_port' with the default value of the
'service.port' value for task-group level connect-enabled services.
2) automatically generate a port-mapping
3) enable an 'expose.checks' flag which automatically creates exposed endpoints
for every compatible consul service check (http/grpc checks on connect
enabled services).
Fix a bug where consul service definitions would not be updated if changes
were made to the service in the Nomad job. Currently this only fixes the
bug for cases where the fix is a matter of updating consul agent's service
registration. There is related bug where destructive changes are required
(see #6877) which will be fixed in another PR.
The enable_tag_override configuration setting for the parent service is
applied to the sidecar service.
Fixes#6459
Consul provides a feature of Service Definitions where the tags
associated with a service can be modified through the Catalog API,
overriding the value(s) configured in the agent's service configuration.
To enable this feature, the flag enable_tag_override must be configured
in the service definition.
Previously, Nomad did not allow configuring this flag, and thus the default
value of false was used. Now, it is configurable.
Because Nomad itself acts as a state machine around the the service definitions
of the tasks it manages, it's worth describing what happens when this feature
is enabled and why.
Consider the basic case where there is no Nomad, and your service is provided
to consul as a boring JSON file. The ultimate source of truth for the definition
of that service is the file, and is stored in the agent. Later, Consul performs
"anti-entropy" which synchronizes the Catalog (stored only the leaders). Then
with enable_tag_override=true, the tags field is available for "external"
modification through the Catalog API (rather than directly configuring the
service definition file, or using the Agent API). The important observation
is that if the service definition ever changes (i.e. the file is changed &
config reloaded OR the Agent API is used to modify the service), those
"external" tag values are thrown away, and the new service definition is
once again the source of truth.
In the Nomad case, Nomad itself is the source of truth over the Agent in
the same way the JSON file was the source of truth in the example above.
That means any time Nomad sets a new service definition, any externally
configured tags are going to be replaced. When does this happen? Only on
major lifecycle events, for example when a task is modified because of an
updated job spec from the 'nomad job run <existing>' command. Otherwise,
Nomad's periodic re-sync's with Consul will now no longer try to restore
the externally modified tag values (as long as enable_tag_override=true).
Fixes#2057
Without a `LocalServicePort`, Connect services will try to use the
mapped port even when delivering traffic locally. A user can override
this behavior by pinning the port value in the `service` stanza but
this prevents us from using the Consul service name to reach the
service.
This commits configures the Consul proxy with its `LocalServicePort`
and `LocalServiceAddress` fields.
* connect: add unix socket to proxy grpc for envoy
Fixes#6124
Implement a L4 proxy from a unix socket inside a network namespace to
Consul's gRPC endpoint on the host. This allows Envoy to connect to
Consul's xDS configuration API.
* connect: pointer receiver on structs with mutexes
* connect: warn on all proxy errors
* taskenv: add connect upstream env vars + test
* set taskenv upstreams instead of appending
* Update client/taskenv/env.go
Co-Authored-By: Michael Schurter <mschurter@hashicorp.com>