Commit Graph

8 Commits

Author SHA1 Message Date
R.B. Boyer d6456fddeb
connect: introduce ExternalSNI field on service-defaults (#6324)
Compiling this will set an optional SNI field on each DiscoveryTarget.
When set this value should be used for TLS connections to the instances
of the target. If not set the default should be used.

Setting ExternalSNI will disable mesh gateway use for that target. It also 
disables several service-resolver features that do not make sense for an 
external service.
2019-08-19 12:19:44 -05:00
R.B. Boyer 91df06098c
xds: improve how envoy metrics are emitted (#6312)
Since generated envoy clusters all are named using (mostly) SNI syntax
we can have envoy read the various fields out of that structure and emit
it as stats labels to the various telemetry backends.

I changed the delimiter for the 'customization hash' from ':' to '~'
because ':' is always reencoded by envoy as '_' when generating metrics
keys.
2019-08-16 09:30:17 -05:00
R.B. Boyer 64fc002e03
connect: fix failover through a mesh gateway to a remote datacenter (#6259)
Failover is pushed entirely down to the data plane by creating envoy
clusters and putting each successive destination in a different load
assignment priority band. For example this shows that normally requests
go to 1.2.3.4:8080 but when that fails they go to 6.7.8.9:8080:

- name: foo
  load_assignment:
    cluster_name: foo
    policy:
      overprovisioning_factor: 100000
    endpoints:
    - priority: 0
      lb_endpoints:
      - endpoint:
          address:
            socket_address:
              address: 1.2.3.4
              port_value: 8080
    - priority: 1
      lb_endpoints:
      - endpoint:
          address:
            socket_address:
              address: 6.7.8.9
              port_value: 8080

Mesh gateways route requests based solely on the SNI header tacked onto
the TLS layer. Envoy currently only lets you configure the outbound SNI
header at the cluster layer.

If you try to failover through a mesh gateway you ideally would
configure the SNI value per endpoint, but that's not possible in envoy
today.

This PR introduces a simpler way around the problem for now:

1. We identify any target of failover that will use mesh gateway mode local or
   remote and then further isolate any resolver node in the compiled discovery
   chain that has a failover destination set to one of those targets.

2. For each of these resolvers we will perform a small measurement of
   comparative healths of the endpoints that come back from the health API for the
   set of primary target and serial failover targets. We walk the list of targets
   in order and if any endpoint is healthy we return that target, otherwise we
   move on to the next target.

3. The CDS and EDS endpoints both perform the measurements in (2) for the
   affected resolver nodes.

4. For CDS this measurement selects which TLS SNI field to use for the cluster
   (note the cluster is always going to be named for the primary target)

5. For EDS this measurement selects which set of endpoints will populate the
   cluster. Priority tiered failover is ignored.

One of the big downsides to this approach to failover is that the failover
detection and correction is going to be controlled by consul rather than
deferring that entirely to the data plane as with the prior version. This also
means that we are bound to only failover using official health signals and
cannot make use of data plane signals like outlier detection to affect
failover.

In this specific scenario the lack of data plane signals is ok because the
effectiveness is already muted by the fact that the ultimate destination
endpoints will have their data plane signals scrambled when they pass through
the mesh gateway wrapper anyway so we're not losing much.

Another related fix is that we now use the endpoint health from the
underlying service, not the health of the gateway (regardless of
failover mode).
2019-08-05 13:30:35 -05:00
R.B. Boyer 4666599e18
connect: reconcile how upstream configuration works with discovery chains (#6225)
* connect: reconcile how upstream configuration works with discovery chains

The following upstream config fields for connect sidecars sanely
integrate into discovery chain resolution:

- Destination Namespace/Datacenter: Compilation occurs locally but using
different default values for namespaces and datacenters. The xDS
clusters that are created are named as they normally would be.

- Mesh Gateway Mode (single upstream): If set this value overrides any
value computed for any resolver for the entire discovery chain. The xDS
clusters that are created may be named differently (see below).

- Mesh Gateway Mode (whole sidecar): If set this value overrides any
value computed for any resolver for the entire discovery chain. If this
is specifically overridden for a single upstream this value is ignored
in that case. The xDS clusters that are created may be named differently
(see below).

- Protocol (in opaque config): If set this value overrides the value
computed when evaluating the entire discovery chain. If the normal chain
would be TCP or if this override is set to TCP then the result is that
we explicitly disable L7 Routing and Splitting. The xDS clusters that
are created may be named differently (see below).

- Connect Timeout (in opaque config): If set this value overrides the
value for any resolver in the entire discovery chain. The xDS clusters
that are created may be named differently (see below).

If any of the above overrides affect the actual result of compiling the
discovery chain (i.e. "tcp" becomes "grpc" instead of being a no-op
override to "tcp") then the relevant parameters are hashed and provided
to the xDS layer as a prefix for use in naming the Clusters. This is to
ensure that if one Upstream discovery chain has no overrides and
tangentially needs a cluster named "api.default.XXX", and another
Upstream does have overrides for "api.default.XXX" that they won't
cross-pollinate against the operator's wishes.

Fixes #6159
2019-08-01 22:03:34 -05:00
R.B. Boyer bd4a2d7be2
connect: allow L7 routers to match on http methods (#6164)
Fixes #6158
2019-07-23 20:56:39 -05:00
R.B. Boyer 67f3da61af
connect: change router syntax for matching query parameters to resemble the syntax for matching paths and headers for consistency. (#6163)
This is a breaking change, but only in the context of the beta series.
2019-07-23 20:55:26 -05:00
R.B. Boyer 6759b5386b
xds: allow http match criteria to be applied to routes on services using grpc protocols (#6149) 2019-07-17 14:07:08 -05:00
R.B. Boyer 72a8195839
implement some missing service-router features and add more xDS testing (#6065)
- also implement OnlyPassing filters for non-gateway clusters
2019-07-12 14:16:21 -05:00