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.
Co-authored-by: Eric Haberkorn <erichaberkorn@gmail.com>
By adding a SpiffeID for server agents, servers can now request a leaf
certificate from the Connect CA.
This new Spiffe ID has a key property: servers are identified by their
datacenter name and trust domain. All servers that share these
attributes will share a ServerURI.
The aim is to use these certificates to verify the server name of ANY
server in a Consul datacenter.
This is the OSS portion of enterprise PR 2460.
Introduces a server-local implementation of the proxycfg.ResolvedServiceConfig
interface that sources data from a blocking query against the server's state
store.
It moves the service config resolution logic into the agent/configentry package
so that it can be used in both the RPC handler and data source.
I've also done a little re-arranging and adding comments to call out data
sources for which there is to be no server-local equivalent.
* draft commit
* add changelog, update test
* remove extra param
* fix test
* update type to account for nil value
* add test for custom passive health check
* update comments and tests
* update description in docs
* fix missing commas
To ease the transition for users, the original gRPC
port can still operate in a deprecated mode as either
plain-text or TLS mode. This behavior should be removed
in a future release whenever we no longer support this.
The resulting behavior from this commit is:
`ports.grpc > 0 && ports.grpc_tls > 0` spawns both plain-text and tls ports.
`ports.grpc > 0 && grpc.tls == undefined` spawns a single plain-text port.
`ports.grpc > 0 && grpc.tls != undefined` spawns a single tls port (backwards compat mode).
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.
Contains 2 changes to the GetEnvoyBootstrapParams response to support
consul-dataplane.
Exposing node_name and node_id:
consul-dataplane will support providing either the node_id or node_name in its
configuration. Unfortunately, supporting both in the xDS meta adds a fair amount
of complexity (partly because most tables are currently indexed on node_name)
so for now we're going to return them both from the bootstrap params endpoint,
allowing consul-dataplane to exchange a node_id for a node_name (which it will
supply in the xDS meta).
Properly setting service for gateways:
To avoid the need to special case gateways in consul-dataplane, service will now
either be the destination service name for connect proxies, or the gateway
service name. This means it can be used as-is in Envoy configuration (i.e. as a
cluster name or in metric tags).
DanStough