Prior to #13244, connect proxies and gateways could only be configured by an
xDS session served by the local client agent.
In an upcoming release, it will be possible to deploy a Consul service mesh
without client agents. In this model, xDS sessions will be handled by the
servers themselves, which necessitates load-balancing to prevent a single
server from receiving a disproportionate amount of load and becoming
overwhelmed.
This introduces a simple form of load-balancing where Consul will attempt to
achieve an even spread of load (xDS sessions) between all healthy servers.
It does so by implementing a concurrent session limiter (limiter.SessionLimiter)
and adjusting the limit according to autopilot state and proxy service
registrations in the catalog.
If a server is already over capacity (i.e. the session limit is lowered),
Consul will begin draining sessions to rebalance the load. This will result
in the client receiving a `RESOURCE_EXHAUSTED` status code. It is the client's
responsibility to observe this response and reconnect to a different server.
Users of the gRPC client connection brokered by the
consul-server-connection-manager library will get this for free.
The rate at which Consul will drain sessions to rebalance load is scaled
dynamically based on the number of proxies in the catalog.
Peerings are terminated when a peer decides to delete the peering from
their end. Deleting a peering sends a termination message to the peer
and triggers them to mark the peering as terminated but does NOT delete
the peering itself. This is to prevent peerings from disappearing from
both sides just because one side deleted them.
Previously the Delete endpoint was skipping the deletion if the peering
was not marked as active. However, terminated peerings are also
inactive.
This PR makes some updates so that peerings marked as terminated can be
deleted by users.
We need to watch for changes to peerings and update the server addresses which get served by the ring buffer.
Also, if there is an active connection for a peer, we are getting up-to-date server addresses from the replication stream and can safely ignore the token's addresses which may be stale.
Previously there was a field indicating the operation that triggered a
secrets write. Now there is a message for each operation and it contains
the secret ID being persisted.
Previously the updates to the peering secrets UUID table relied on
inferring what action triggered the update based on a reconciliation
against the existing secrets.
Instead we now explicitly require the operation to be given so that the
inference isn't necessary. This makes the UUID table logic easier to
reason about and fixes some related bugs.
There is also an update so that the peering secrets get handled on
snapshots/restores.
Dialers do not keep track of peering secret UUIDs, so they should not
attempt to clean up data from that table when their peering is deleted.
We also now keep peer server addresses when marking peerings for
deletion. Peer server addresses are used by the ShouldDial() helper
when determining whether the peering is for a dialer or an acceptor.
We need to keep this data so that peering secrets can be cleaned up
accordingly.
* defaulting to false because peering will be released as beta
* Ignore peering disabled error in bundles cachetype
Co-authored-by: Matt Keeler <mkeeler@users.noreply.github.com>
Co-authored-by: freddygv <freddy@hashicorp.com>
Co-authored-by: Matt Keeler <mjkeeler7@gmail.com>
Update generate token endpoint (rpc, http, and api module)
If ServerExternalAddresses are set, it will override any addresses gotten from the "consul" service, and be used in the token instead, and dialed by the dialer. This allows for setting up a load balancer for example, in front of the consul servers.
Ensure that the peer stream replication rpc can successfully be used with TLS activated.
Also:
- If key material is configured for the gRPC port but HTTPS is not
enabled now TLS will still be activated for the gRPC port.
- peerstream replication stream opened by the establishing-side will now
ignore grpc.WithBlock so that TLS errors will bubble up instead of
being awkwardly delayed or suppressed
Previously, public referred to gRPC services that are both exposed on
the dedicated gRPC port and have their definitions in the proto-public
directory (so were considered usable by 3rd parties). Whereas private
referred to services on the multiplexed server port that are only usable
by agents and other servers.
Now, we're splitting these definitions, such that external/internal
refers to the port and public/private refers to whether they can be used
by 3rd parties.
This is necessary because the peering replication API needs to be
exposed on the dedicated port, but is not (yet) suitable for use by 3rd
parties.
Peer replication is intended to be between separate Consul installs and
effectively should be considered "external". This PR moves the peer
stream replication bidirectional RPC endpoint to the external gRPC
server and ensures that things continue to function.
These changes are primarily for Consul's UI, where we want to be more
specific about the state a peering is in.
- The "initial" state was renamed to pending, and no longer applies to
peerings being established from a peering token.
- Upon request to establish a peering from a peering token, peerings
will be set as "establishing". This will help distinguish between the
two roles: the cluster that generates the peering token and the
cluster that establishes the peering.
- When marked for deletion, peering state will be set to "deleting".
This way the UI determines the deletion via the state rather than the
"DeletedAt" field.
Co-authored-by: freddygv <freddy@hashicorp.com>
This is the OSS portion of enterprise PR 2056.
This commit provides server-local implementations of the proxycfg.ConfigEntry
and proxycfg.ConfigEntryList interfaces, that source data from streaming events.
It makes use of the LocalMaterializer type introduced for peering replication,
adding the necessary support for authorization.
It also adds support for "wildcard" subscriptions (within a topic) to the event
publisher, as this is needed to fetch service-resolvers for all services when
configuring mesh gateways.
Currently, events will be emitted for just the ingress-gateway, service-resolver,
and mesh config entry types, as these are the only entries required by proxycfg
— the events will be emitted on topics named IngressGateway, ServiceResolver,
and MeshConfig topics respectively.
Though these events will only be consumed "locally" for now, they can also be
consumed via the gRPC endpoint (confirmed using grpcurl) so using them from
client agents should be a case of swapping the LocalMaterializer for an
RPCMaterializer.
When traversing an exported peered service, the discovery chain
evaluation at the other side may re-route the request to a variety of
endpoints. Furthermore we intend to terminate mTLS at the mesh gateway
for arriving peered traffic that is http-like (L7), so the caller needs
to know the mesh gateway's SpiffeID in that case as well.
The following new SpiffeID values will be shipped back in the peerstream
replication:
- tcp: all possible SpiffeIDs resulting from the service-resolver
component of the exported discovery chain
- http-like: the SpiffeID of the mesh gateway
This is only configured in xDS when a service with an L7 protocol is
exported.
They also load any relevant trust bundles for the peered services to
eventually use for L7 SPIFFE validation during mTLS termination.
When our peer deletes the peering it is locally marked as terminated.
This termination should kick off deleting all imported data, but should
not delete the peering object itself.
Keeping peerings marked as terminated acts as a signal that the action
took place.
Once a peering is marked for deletion a new leader routine will now
clean up all imported resources and then the peering itself.
A lot of the logic was grabbed from the namespace/partitions deferred
deletions but with a handful of simplifications:
- The rate limiting is not configurable.
- Deleting imported nodes/services/checks is done by deleting nodes with
the Txn API. The services and checks are deleted as a side-effect.
- There is no "round rate limiter" like with namespaces and partitions.
This is because peerings are purely local, and deleting a peering in
the datacenter does not depend on deleting data from other DCs like
with WAN-federated namespaces. All rate limiting is handled by the
Raft rate limiter.
1. Fix a bug where the peering leader routine would not track all active
peerings in the "stored" reconciliation map. This could lead to
tearing down streams where the token was generated, since the
ConnectedStreams() method used for reconciliation returns all streams
and not just the ones initiated by this leader routine.
2. Fix a race where stream contexts were being canceled before
termination messages were being processed by a peer.
Previously the leader routine would tear down streams by canceling
their context right after the termination message was sent. This
context cancelation could be propagated to the server side faster
than the termination message. Now there is a change where the
dialing peer uses CloseSend() to signal when no more messages will
be sent. Eventually the server peer will read an EOF after receiving
and processing the preceding termination message.
Using CloseSend() is actually not enough to address the issue
mentioned, since it doesn't wait for the server peer to finish
processing messages. Because of this now the dialing peer also reads
from the stream until an error signals that there are no more
messages. Receiving an EOF from our peer indicates that they
processed the termination message and have no additional work to do.
Given that the stream is being closed, all the messages received by
Recv are discarded. We only check for errors to avoid importing new
data.
When deleting a peering we do not want to delete the peering and all
imported data in a single operation, since deleting a large amount of
data at once could overload Consul.
Instead we defer deletion of peerings so that:
1. When a peering deletion request is received via gRPC the peering is
marked for deletion by setting the DeletedAt field.
2. A leader routine will monitor for peerings that are marked for
deletion and kick off a throttled deletion of all imported resources
before deleting the peering itself.
This commit mostly addresses point #1 by modifying the peering service
to mark peerings for deletion. Another key change is to add a
PeeringListDeleted state store function which can return all peerings
marked for deletion. This function is what will be watched by the
deferred deletion leader routine.
Previously, imported data would never be deleted. As
nodes/services/checks were registered and deregistered, resources
deleted from the exporting cluster would accumulate in the imported
cluster.
This commit makes updates to replication so that whenever an update is
received for a service name we reconcile what was present in the catalog
against what was received.
This handleUpdateService method can handle both updates and deletions.
When converting from Consul intentions to xds RBAC rules, services imported from other peers must encode additional data like partition (from the remote cluster) and trust domain.
This PR updates the PeeringTrustBundle to hold the sending side's local partition as ExportedPartition. It also updates RBAC code to encode SpiffeIDs of imported services with the ExportedPartition and TrustDomain.
Require use of mesh gateways in order for service mesh data plane
traffic to flow between peers.
This also adds plumbing for envoy integration tests involving peers, and
one starter peering test.
Mesh gateways will now enable tcp connections with SNI names including peering information so that those connections may be proxied.
Note: this does not change the callers to use these mesh gateways.
