The Destination controller can panic due to a nil-deref when
the EndpointSlices API is enabled.
This change updates the controller to properly initialize values
to avoid this segmentation fault.
Fixes#5521
Signed-off-by: Oleg Ozimok <oleg.ozimok@corp.kismia.com>
Ignore pods with status.phase=Succeeded when watching IP addresses
When a pod terminates successfully, some CNIs will assign its IP address
to newly created pods. This can lead to duplicate pod IPs in the same
Kubernetes cluster.
Filter out pods which are in a Succeeded phase since they are not
routable anymore.
Fixes#5394
Signed-off-by: fpetkovski <filip.petkovsky@gmail.com>
The destination service now returns `OpaqueTransport` hint when the annotation
matches the resolve target port. This is different from the current behavior
which always sets the hint when a proxy is present.
Closes#5421
This happens by changing the endpoint watcher to set a pod's opaque port
annotation in certain cases. If the pod already has an annotation, then its
value is used. If the pod has no annotation, then it checks the namespace that
the endpoint belongs to; if it finds an annotation on the namespace then it
overrides the pod's annotation value with that.
Signed-off-by: Kevin Leimkuhler <kevin@kleimkuhler.com>
Context: #5209
This updates the destination service to set the `Endpoint` field in `GetProfile`
responses.
The `Endpoint` field is only set if the IP maps to a Pod--not a Service.
Additionally in this scenario, the default Service Profile is used as the base
profile so no other significant fields are set.
### Examples
```
# GetProfile for an IP that maps to a Service
❯ go run controller/script/destination-client/main.go -method getProfile -path 10.43.222.0:9090
INFO[0000] fully_qualified_name:"linkerd-prometheus.linkerd.svc.cluster.local" retry_budget:{retry_ratio:0.2 min_retries_per_second:10 ttl:{seconds:10}} dst_overrides:{authority:"linkerd-prometheus.linkerd.svc.cluster.local.:9090" weight:10000}
```
Before:
```
# GetProfile for an IP that maps to a Pod
❯ go run controller/script/destination-client/main.go -method getProfile -path 10.42.0.20
INFO[0000] retry_budget:{retry_ratio:0.2 min_retries_per_second:10 ttl:{seconds:10}}
```
After:
```
# GetProfile for an IP that maps to a Pod
❯ go run controller/script/destination-client/main.go -method getProfile -path 10.42.0.20
INFO[0000] retry_budget:{retry_ratio:0.2 min_retries_per_second:10 ttl:{seconds:10}} endpoint:{addr:{ip:{ipv4:170524692}} weight:10000 metric_labels:{key:"control_plane_ns" value:"linkerd"} metric_labels:{key:"deployment" value:"fast-1"} metric_labels:{key:"pod" value:"fast-1-5cc87f64bc-9hx7h"} metric_labels:{key:"pod_template_hash" value:"5cc87f64bc"} metric_labels:{key:"serviceaccount" value:"default"} tls_identity:{dns_like_identity:{name:"default.default.serviceaccount.identity.linkerd.cluster.local"}} protocol_hint:{h2:{}}}
```
Signed-off-by: Kevin Leimkuhler <kevin@kleimkuhler.com>
Fixes#4191#4993
This bumps Kubernetes client-go to the latest v0.19.2 (We had to switch directly to 1.19 because of this issue). Bumping to v0.19.2 required upgrading to smi-sdk-go v0.4.1. This also depends on linkerd/stern#5
This consists of the following changes:
- Fix ./bin/update-codegen.sh by adding the template path to the gen commands, as it is needed after we moved to GOMOD.
- Bump all k8s related dependencies to v0.19.2
- Generate CRD types, client code using the latest k8s.io/code-generator
- Use context.Context as the first argument, in all code paths that touch the k8s client-go interface
Signed-off-by: Tarun Pothulapati <tarunpothulapati@outlook.com>
[Link to RFC](https://github.com/linkerd/rfc/pull/23)
### What
---
* PR that puts together all past pieces of the puzzle to deliver topology-aware service routing, as specified in the [Kubernetes docs](https://kubernetes.io/docs/concepts/services-networking/service-topology/) but with a much better load balancing algorithm and all the coolness of linkerd :)
* The first piece of this PR is focused on adding topology metadata: topology preference for services and topology `<k,v>` pairs for endpoints.
* The second piece of this PR puts together the new context format and fetching the source node topology metadata in order to allow for endpoints filtering.
* The final part is doing the filtering -- passing all of the metadata to the listener and on every `Add` filtering endpoints based on the topology preference of the service, topology `<k,v>` pairs of endpoints and topology of the source (again `<k,v>` pairs).
### How
---
* **Collecting metadata**:
- Services do not have values for topology keys -- the topological keys defined in a service's spec are only there to dictate locality preference for routing; as such, I decided to store them in an array, they will be taken exactly as they are found in the service spec, this ensures we respect the preference order.
- For EndpointSlices, we are using a map -- an EndpointSlice has locality information in the form of `<k,v>` pair, where the key is a topological key (similar to what's listed in the service) and the value is the locality information -- e.g `hostname: minikube`. For each address we now have a map of topology values which gets populated when we translate the endpoints to an address set. Because normal Endpoints do not have any topology information, we create each address with an empty map which is subsequently populated ONLY for slices in the `endpointSliceToAddressSet` function.
* **Filtering endpoints**:
- This was a tricky part and filled me with doubts. I think there are a few ways to do this, but this is how I "envisioned" it. First, the `endpoint_translator.go` should be the one to do the filtering; this means that on subscription, we need to feed all of the relevant metadata to the listener. To do this, I created a new function `AddTopologyFilter` as part of the listener interface.
- To complement the `AddTopologyFilter` function, I created a new `TopologyFilter` struct in `endpoints_watcher.go`. I then embedded this structure in all listeners that implement the interface. The structure holds the source topology (source node), a boolean to tell if slices are activated in case we need to double check (or write tests for the function) and the service preference. We create the filter on Subscription -- we have access to the k8s client here as well as the service, so it's the best point to collect all of this data together. Addresses all have their own topology added to them so they do not have to be collected by the filter.
- When we add a new set of addresses, we check to see if slices are enabled -- chances are if slices are enabled, service topology might be too. This lets us skip this step if the latest version is not adopted. Prior to sending an `Add` we filter the endpoints -- if the preference is registered by the filter we strictly enforce it, otherwise nothing changes.
And that's pretty much it.
Signed-off-by: Matei David <matei.david.35@gmail.com>
This PR corrects misspellings identified by the [check-spelling action](https://github.com/marketplace/actions/check-spelling).
The misspellings have been reported at aaf440489e (commitcomment-41423663)
The action reports that the changes in this PR would make it happy: 5b82c6c5ca
Note: this PR does not include the action. If you're interested in running a spell check on every PR and push, that can be offered separately.
Signed-off-by: Josh Soref <jsoref@users.noreply.github.com>
* Small PR that uncomments the `EndpointSliceAcess` method and cleans up left over todos in the destination service.
* Based on the past three PRs related to `EndpointSlices` (#4663#4696#4740); they should now be functional (albeit prone to bugs) and ready to use.
Signed-off-by: Matei David <matei.david.35@gmail.com>
EndpointSlices have been made opt-in due to their experimental nature. This PR
introduces a new install flag 'enableEndpointSlices' that will allow adopters to
specify in their cli install or helm install step whether they would like to
use endpointslices as a resource in the destination service, instead of the
endpoints k8s resource.
Signed-off-by: Matei David <matei.david.35@gmail.com>
## Motivation
Closes#3916
This adds the ability to get profiles for services by IP address.
### Change in behavior
When the destination server receives a `GetProfile` request with an IP address,
it now tries to map that IP address to a service.
If the IP address maps to an existing service, then the destination server
returns the profile stream subscribes for updates to the _service_--this is the
existing behavior. If the IP changes to a new service, the stream will still
send updates for the first service the IP address corresponded to since that is
what it is subscribed to.
If the IP address does not map to an existing service, then the destination
server returns the profile stream but does not subscribe for updates. The stream
will receive one update, the default profile.
### Solution
This change uses the `IPWatcher` within the destination server to check for what
services an IP address correspond to. By adding a new method `GetSvc` to
`IPWatcher`, the server now calls this method if `GetProfile` receives a request
with an IP address.
## Testing
Install linkerd on a cluster and get the cluster IP of any service:
```bash
❯ kubectl get -n linkerd svc/linkerd-tap -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
linkerd-tap ClusterIP 10.104.57.90 <none> 8088/TCP,443/TCP 16h linkerd.io/control-plane-component=tap
```
Run the destination server:
```bash
❯ go run controller/cmd/main.go destination -kubeconfig ~/.kube/config
```
Get the profile for the tap service by IP address:
```bash
❯ go run controller/script/destination-client/main.go -method getProfile -path 10.104.57.90:8088
INFO[0000] retry_budget:{retry_ratio:0.2 min_retries_per_second:10 ttl:{seconds:10}}
INFO[0000]
```
Get the profile for an IP address that does not correspond to a service:
```bash
❯ go run controller/script/destination-client/main.go -method getProfile -path 10.256.0.1:8088
INFO[0000] retry_budget:{retry_ratio:0.2 min_retries_per_second:10 ttl:{seconds:10}}
INFO[0000]
```
You can add and remove settings for the service profile for tap and get updates.
Signed-off-by: Kevin Leimkuhler <kevin@kleimkuhler.com>
Introduce support for the EndpointSlice k8s resource (k8s v1.16+) in the destination service.
Through this PR, in the EndpointsWatcher, there will be a dedicated informer for EndpointSlice;
the informer cannot run at the same time as the Endpoints resource informer. The main difference
is that EndpointSlices have a one-to-many relationship with a service, they provide better performance benefits,
dual-stack addresses and more. EndpointSlice support also implies service topology and other k8s related features.
Validated and tested manually, as well as with dedicated unit tests.
Closes#4501
Signed-off-by: Matei David <matei.david.35@gmail.com>
This change adds labels to endpoints that target remote services. It also adds a Grafana dashboard that can be used to monitor multicluster traffic.
Signed-off-by: Zahari Dichev <zaharidichev@gmail.com>
When the proxy has an IP watch on a pod and the destination controller gets a pod update event, the destination controller sends a NoEndpoints message to all listeners followed by an Add with the new pod state. This can result in the proxy's load balancer being briefly empty and could result in failing requests in the period.
Since consecutive Add events with the same address will override each other, we can simply send the Adds without needing to clear the previous state with a NoEndpoints message.
Here we upgrade our dependencies on client-go to 0.17.4 and smi-sdk-go to 0.3.0. Since smi-sdk-go uses client-go 0.17.4, these upgrades must be performed simultaneously.
This also requires simultaneously upgrading our dependency on linkerd/stern to a SHA which also uses client-go 0.17.4. This keeps all of our transitive dependencies synchronized on one version of client-go.
This ALSO requires updating our codegen scripts to use the 0.17.4 version of code-generator and running it to generate 0.17.4 compatible generated code. I took this opportunity to update our code generation script to properly use the version of code-generater from `go.mod` rather than a hardcoded SHA.
Signed-off-by: Alex Leong <alex@buoyant.io>
This change removes the target port requirement when resolving ports in the dst service. Based on the comments, it seems that we need to have a target port defined in the port spec in order to resolve to the port in the Endpoints. In reality if target port is note defined when creating the service, k8s will set the port and the target port to the same value. Seems to me that checking for the targetPort to be different than 0, is a no-op.
Signed-off-by: Zahari Dichev zaharidichev@gmail.com
This PR introduces a service mirroring component that is responsible for watching remote clusters and mirroring their services locally.
Signed-off-by: Zahari Dichev <zaharidichev@gmail.com>
Fixes#3444Fixes#3443
## Background and Behavior
This change adds support for the destination service to resolve Get requests which contain a service clusterIP or pod ip as the `Path` parameter. It returns the stream of endpoints, just as if `Get` had been called with the service's authority. This lays the groundwork for allowing the proxy to TLS TCP connections by allowing the proxy to do destination lookups for the SO_ORIG_DST of tcp connections. When that ip address corresponds to a service cluster ip or pod ip, the destination service will return the endpoints stream, including the pod metadata required to establish identity.
Prior to this change, attempting to look up an ip address in the destination service would result in a `InvalidArgument` error.
Updating the `GetProfile` method to support ip address lookups is out of scope and attempts to look up an ip address with the `GetProfile` method will result in `InvalidArgument`.
## Implementation
We do this by creating a `IPWatcher` which wraps the `EndpointsWatcher` and supports lookups by ip. `IPWatcher` maintains a mapping up clusterIPs to service ids and translates subscriptions to an IP address into a subscription to the service id using the underlying `EndpointsWatcher`.
Since the service name is no longer always infer-able directly from the input parameters, we restructure `EndpointTranslator` and `PodSet` so that we propagate the service name from the endpoints API response.
## Testing
This can be tested by running the destination service locally, using the current kube context to connect to a Kubernetes cluster:
```
go run controller/cmd/main.go destination -kubeconfig ~/.kube/config
```
Then lookups can be issued using the destination client:
```
go run controller/script/destination-client/main.go -path 192.168.54.78:80 -method get -addr localhost:8086
```
Service cluster ips and pod ips can be used as the `path` argument.
Signed-off-by: Alex Leong <alex@buoyant.io>
CI currently enforcing formatting rules by using the fmt linter of golang-ci-lint which is invoked from the bin/lint script. However it doesn't seem possible to use golang-ci-lint as a formatter, only as a linter which checks formatting. This means any formatter used by your IDE or invoked manually may or may not use the same formatting rules as golang-ci-lint depending on which formatter you use and which specific revision of that formatter you use.
In this change we stop using golang-ci-lint for format checking. We introduce `tools.go` and add goimports to the `go.mod` and `go.sum` files. This allows everyone to easily get the same revision of goimports by running `go install -mod=readonly golang.org/x/tools/cmd/goimports` from inside of the project. We add a step in the CI workflow that uses goimports via the `bin/fmt` script to check formatting.
Some shell gymnastics were required in the `bin/fmt` script to work around some limitations of `goimports`:
* goimports does not have a built-in mechanism for excluding directories, and we need to exclude the vendor director as well as the generated Go sources
* goimports returns a 0 exit code, even when formatting errors are detected
Signed-off-by: Alex Leong <alex@buoyant.io>
* The linkerd proxy does not work with headless services (i.e. endpoints not referencing a pod).
Changed endpoints_watcher to also return endpoints with no targetref.
Fixes#3308
Signed-off-by: Johannes Hansen <johannesh1980@gmail.com>
* Fix panic in endpoint_translator
Signed-off-by: Johannes Hansen <johannesh1980@gmail.com>
* Avoid the dashboard requesting stats when not needed
Create an alternative to `urlsForResource` called
`urlsForResourceNoStats` that makes use of the `skip_stats` parameter in
the stats API (created in #1871) that doesn't query Prometheus when not needed.
When testing using the dashboard looking at the linkerd namespace,
queries per second went down from 2874 to 2756, a 4% decrease.
Signed-off-by: Alejandro Pedraza <alejandro@buoyant.io>
* Have the proxy-injector emit events upon injection/skipping injection
Fixes#3253
Have the proxy-injector emit an event whenever a injection happens, or
when injection is skipped for some reason (also added that reason into
the proxy-injector logs). The level is associated to the parent workload
(it can't be associated to the pod because at this point the pod hasn't
been persisted).
The event recorder was setup at the `webhook/server.go` level and passed
to the proxy-injector's `Inject` function. The sp-validator thus also
has access to the event recorder, but for now it's not using it.
Related changes:
- Refactored `api.GetOwnerKindAndName()` to have it return a more
generic object.
- Refactored `report.Injectable()` to also have it return the reason why
a workload is not injectable.
Signed-off-by: Alejandro Pedraza <alejandro@buoyant.io>
Fixes https://github.com/linkerd/linkerd2/issues/2800#issuecomment-513740498
When the Linkerd proxy sends a query for a Kubernetes external name service to the destination service, the destination service returns `NoEndpoints: exists=false` because an external name service has no endpoints resource. Due to a change in the proxy's fallback logic, this no longer causes the proxy to fallback to either DNS or SO_ORIG_DST and instead fails the request. The net effect is that Linkerd fails all requests to external name services.
We change the destination service to instead return `InvalidArgument` for external name services. This causes the proxy to fallback to SO_ORIG_DST instead of failing the request.
Signed-off-by: Alex Leong <alex@buoyant.io>
The destination service's endpoints watcher assumed every `Endpoints`
object contained a `TargetRef`. This field is optional, and in cases
such as the default `ep/kubernetes` object, `TargetRef` is nil, causing
a nil pointer dereference.
Fix endpoints watcher to check for `TargetRef` prior to dereferencing.
Signed-off-by: Andrew Seigner <siggy@buoyant.io>
We add support for looking up individual pods in a stateful set with the destination service. This allows Linkerd to correctly proxy requests which address individual pods. The authority structure for such a request is `<pod-name>.<service>.<namespace>.svc.cluster.local:<port>`.
Fixes#2266
Signed-off-by: Alex Leong <alex@buoyant.io>
The openAPIV3Schema validation in the ServiceProfiles CRD is very limited in what it can validate and is obviated by more sophisticated validation done by the validating admission controller. Therefore, we would like to remove the openAPIV3Schema validation to reduce the size and complexity of the CRD object.
To do so, we must also bump the version of the ServiceProfile custom resource from v1alpha1 to v1alpha2. This ensures that when the controller is upgraded, it will attempt to watch the v1alpha2 resource. If it cannot (because, for example, the controller pod started before the ServiceProfile CRD was updated and therefore the v1alpha2 version does not exist) then it will go into a crash loop backoff until it can. This essentially means that the controller will wait for the CRD to be upgraded to include v1alpha2 before it will start.
Bumping the version is necessary because if we did not, it would be possible for the controller to start before the CRD is updated (removing the validation). In this case, when the CRD is edited, the controller will lose its list watch on ServiceProfiles and will stop getting updates.
Signed-off-by: Alex Leong <alex@buoyant.io>
* Allow custom cluster domain in destination watcher
The change relaxes the constrains of an authority requiring a
`svc.cluster.local` suffix to only require `svc` as third part.
A unit test could be added though the destination/server and endpoint
watcher already test this behaviour.
* Update proto to allow setting custom cluster domain
Update golden templates
* Allow setting custom domain in grpc, web server
* Remove cluster domain flags from web srv and public api
* Set defaultClusterDomain in validateAndBuild if none is set
Signed-off-by: Armin Buerkle <armin.buerkle@alfatraining.de>
To give better visibility into the inner workings of the kubernetes watchers in the destination service, we add some prometheus metrics.
Signed-off-by: Alex Leong <alex@buoyant.io>
This change implements the DstOverrides feature of the destination profile API (aka traffic splitting).
We add a TrafficSplitWatcher to the destination service which watches for TrafficSplit resources and notifies subscribers about TrafficSplits for services that they are subscribed to. A new TrafficSplitAdaptor then merges the TrafficSplit logic into the DstOverrides field of the destination profile.
Signed-off-by: Alex Leong <alex@buoyant.io>
* Have `GetOwnerKindAndName` be able to skip the cache
Refactored `GetOwnerKindAndName` so it can optionally skip the
shared informer cache and instead hit the k8s API directly.
Useful for the proxy injector, when the pod's replicaset got just
created and might not be in ready in the cache yet.
Fixes#2738
Signed-off-by: Alejandro Pedraza <alejandro@buoyant.io>
This is a major refactor of the destination service. The goals of this refactor are to simplify the code for improved maintainability. In particular:
* Remove the "resolver" interfaces. These were a holdover from when our decision tree was more complex about how to handle different kinds of authorities. The current implementation only accepts fully qualified kubernetes service names and thus this was an unnecessary level of indirection.
* Moved the endpoints and profile watchers into their own package for a more clear separation of concerns. These watchers deal only in Kubernetes primitives and are agnostic to how they are used. This allows a cleaner layering when we use them from our gRPC service.
* Renamed the "listener" types to "translator" to make it more clear that the function of these structs is to translate kubernetes updates from the watcher to gRPC messages.
Signed-off-by: Alex Leong <alex@buoyant.io>
Oleh Ozimok
Filip Petkovski
Alejandro Pedraza
Kevin Leimkuhler
Tarun Pothulapati
Matei David
Josh Soref
Alex Leong
Zahari Dichev
Johannes Hansen
陈谭军
Guangming Wang
Andrew Seigner
arminbuerkle