A check may be set to become passing/critical only if a specified number of successive
checks return passing/critical in a row. Status will stay identical as before until
the threshold is reached.
This feature is available for HTTP, TCP, gRPC, Docker & Monitor checks.
Fixes: #5396
This PR adds a proxy configuration stanza called expose. These flags register
listeners in Connect sidecar proxies to allow requests to specific HTTP paths from outside of the node. This allows services to protect themselves by only
listening on the loopback interface, while still accepting traffic from non
Connect-enabled services.
Under expose there is a boolean checks flag that would automatically expose all
registered HTTP and gRPC check paths.
This stanza also accepts a paths list to expose individual paths. The primary
use case for this functionality would be to expose paths for third parties like
Prometheus or the kubelet.
Listeners for requests to exposed paths are be configured dynamically at run
time. Any time a proxy, or check can be registered, a listener can also be
created.
In this initial implementation requests to these paths are not
authenticated/encrypted.
Also:
* Finished threading replaceExistingChecks setting (from GH-4905)
through service manager.
* Respected the original configSource value that was used to register a
service or a check when restoring persisted data.
* Run several existing tests with and without central config enabled
(not exhaustive yet).
* Switch to ioutil.ReadFile for all types of agent persistence.
The embedded `Server` field on a `DNSServer` is only set inside of the
`ListenAndServe` method. If that method fails for reasons like the
address being in use and is not bindable, then the `Server` field will
not be set and the overall `Agent.Start()` will fail.
This will trigger the inner loop of `TestAgent.Start()` to invoke
`ShutdownEndpoints` which will attempt to pretty print the DNS servers
using fields on that inner `Server` field. Because it was never set,
this causes a nil pointer dereference and crashes the test.
This fixes pathological cases where the write throughput and snapshot size are both so large that more than 10k log entries are written in the time it takes to restore the snapshot from disk. In this case followers that restart can never catch up with leader replication again and enter a loop of constantly downloading a full snapshot and restoring it only to find that snapshot is already out of date and the leader has truncated its logs so a new snapshot is sent etc.
In general if you need to adjust this, you are probably abusing Consul for purposes outside its design envelope and should reconsider your usage to reduce data size and/or write volume.
* Support for maximum size for Output of checks
This PR allows users to limit the size of output produced by checks at the agent
and check level.
When set at the agent level, it will limit the output for all checks monitored
by the agent.
When set at the check level, it can override the agent max for a specific check but
only if it is lower than the agent max.
Default value is 4k, and input must be at least 1.
* Improve startup message to avoid confusing users when no error occurs
Several times, some users not very familiar with Consul get confused
by error message at startup:
`[INFO] agent: (LAN) joined: 1 Err: <nil>`
Having `Err: <nil>` seems weird to many users, I propose to have the
following instead:
* Success: `[INFO] agent: (LAN) joined: 1`
* Error: `[WARN] agent: (LAN) couldn't join: %d Err: ERROR`
Roles are named and can express the same bundle of permissions that can
currently be assigned to a Token (lists of Policies and Service
Identities). The difference with a Role is that it not itself a bearer
token, but just another entity that can be tied to a Token.
This lets an operator potentially curate a set of smaller reusable
Policies and compose them together into reusable Roles, rather than
always exploding that same list of Policies on any Token that needs
similar permissions.
This also refactors the acl replication code to be semi-generic to avoid
3x copypasta.
* Move the watch package into the api module
It was already just a thin wrapper around the API anyways. The biggest change was to the testing. Instead of using a test agent directly from the agent package it now uses the binary on the PATH just like the other API tests.
The other big changes were to fix up the connect based watch tests so that we didn’t need to pull in the connect package (and therefore all of Consul)
The DNS config parameters `recursors` and `dns_config.*` are now hot
reloaded on SIGHUP or `consul reload` and do not need an agent restart
to be modified.
Config is stored in an atomic.Value and loaded at the beginning of each
request. Reloading only affects requests that start _after_ the
reload. Ongoing requests are not affected. To match the current
behavior the recursor handler is loaded and unloaded as needed on config
reload.
This PR introduces reloading tls configuration. Consul will now be able to reload the TLS configuration which previously required a restart. It is not yet possible to turn TLS ON or OFF with these changes. Only when TLS is already turned on, the configuration can be reloaded. Most importantly the certificates and CAs.
Prevent race between register and deregister requests by saving them
together in the local state on registration.
Also adds more cleaning in case of failure when registering services
/ checks.
This PR adds two features which will be useful for operators when ACLs are in use.
1. Tokens set in configuration files are now reloadable.
2. If `acl.enable_token_persistence` is set to `true` in the configuration, tokens set via the `v1/agent/token` endpoint are now persisted to disk and loaded when the agent starts (or during configuration reload)
Note that token persistence is opt-in so our users who do not want tokens on the local disk will see no change.
Some other secondary changes:
* Refactored a bunch of places where the replication token is retrieved from the token store. This token isn't just for replicating ACLs and now it is named accordingly.
* Allowed better paths in the `v1/agent/token/` API. Instead of paths like: `v1/agent/token/acl_replication_token` the path can now be just `v1/agent/token/replication`. The old paths remain to be valid.
* Added a couple new API functions to set tokens via the new paths. Deprecated the old ones and pointed to the new names. The names are also generally better and don't imply that what you are setting is for ACLs but rather are setting ACL tokens. There is a minor semantic difference there especially for the replication token as again, its no longer used only for ACL token/policy replication. The new functions will detect 404s and fallback to using the older token paths when talking to pre-1.4.3 agents.
* Docs updated to reflect the API additions and to show using the new endpoints.
* Updated the ACL CLI set-agent-tokens command to use the non-deprecated APIs.
This PR is based on #5366 and continues to centralise the tls configuration in order to be reloadable eventually!
This PR is another refactoring. No tests are changed, beyond calling other functions or cosmetic stuff. I added a bunch of tests, even though they might be redundant.
In order to be able to reload the TLS configuration, we need one way to generate the different configurations.
This PR introduces a `tlsutil.Configurator` which holds a `tlsutil.Config`. Afterwards it is responsible for rendering every `tls.Config`. In this particular PR I moved `IncomingHTTPSConfig`, `IncomingTLSConfig`, and `OutgoingTLSWrapper` into `tlsutil.Configurator`.
This PR is a pure refactoring - not a single feature added. And not a single test added. I only slightly modified existing tests as necessary.
Adds two new configuration parameters "dns_config.use_cache" and
"dns_config.cache_max_age" controlling how DNS requests use the agent
cache when querying servers.
Currently the gRPC server assumes that if you have configured TLS
certs on the agent (for RPC) that you want gRPC to be encrypted.
If gRPC is bound to localhost this can be overkill. For the API we
let the user choose to offer HTTP or HTTPS API endpoints
independently of the TLS cert configuration for a similar reason.
This setting will let someone encrypt RPC traffic with TLS but avoid
encrypting local gRPC traffic if that is what they want to do by only
enabling TLS on gRPC if the HTTPS API port is enabled.
* Support rate limiting and concurrency limiting CSR requests on servers; handle CA rotations gracefully with jitter and backoff-on-rate-limit in client
* Add CSR rate limiting docs
* Fix config naming and add tests for new CA configs
For established xDS gRPC streams recheck ACLs for each DiscoveryRequest
or DiscoveryResponse. If more than 5 minutes has elapsed since the last
ACL check, recheck even without an incoming DiscoveryRequest or
DiscoveryResponse. ACL failures will terminate the stream.
* Add State storage and LastResult argument into Cache so that cache.Types can safely store additional data that is eventually expired.
* New Leaf cache type working and basic tests passing. TODO: more extensive testing for the Root change jitter across blocking requests, test concurrent fetches for different leaves interact nicely with rootsWatcher.
* Add multi-client and delayed rotation tests.
* Typos and cleanup error handling in roots watch
* Add comment about how the FetchResult can be used and change ca leaf state to use a non-pointer state.
* Plumb test override of root CA jitter through TestAgent so that tests are deterministic again!
* Fix failing config test
* Add default weights when adding a service with no weights to local state to prevent constant AE re-sync.
This fix was contributed by @42wim in https://github.com/hashicorp/consul/pull/5096 but was merged against the wrong base. This adds it to master and adds a test to cover the behaviour.
* Fix tests that broke due to comparing internal state which now has default weights
Fixes point `#2` of: https://github.com/hashicorp/consul/issues/4903
When registering a service each healthcheck status is saved and restored (https://github.com/hashicorp/consul/blob/master/agent/agent.go#L1914) to avoid unnecessary flaps in health state.
This change extends this feature to single check registration by moving this protection in `AddCheck()` so that both `PUT /v1/agent/service/register` and `PUT /v1/agent/check/register` behave in the same idempotent way.
#### Steps to reproduce
1. Register a check :
```
curl -X PUT \
http://127.0.0.1:8500/v1/agent/check/register \
-H 'Content-Type: application/json' \
-d '{
"Name": "my_check",
"ServiceID": "srv",
"Interval": "10s",
"Args": ["true"]
}'
```
2. The check will initialize and change to `passing`
3. Run the same request again
4. The check status will quickly go from `critical` to `passing` (the delay for this transission is determined by https://github.com/hashicorp/consul/blob/master/agent/checks/check.go#L95)
This PR is almost a complete rewrite of the ACL system within Consul. It brings the features more in line with other HashiCorp products. Obviously there is quite a bit left to do here but most of it is related docs, testing and finishing the last few commands in the CLI. I will update the PR description and check off the todos as I finish them over the next few days/week.
Description
At a high level this PR is mainly to split ACL tokens from Policies and to split the concepts of Authorization from Identities. A lot of this PR is mostly just to support CRUD operations on ACLTokens and ACLPolicies. These in and of themselves are not particularly interesting. The bigger conceptual changes are in how tokens get resolved, how backwards compatibility is handled and the separation of policy from identity which could lead the way to allowing for alternative identity providers.
On the surface and with a new cluster the ACL system will look very similar to that of Nomads. Both have tokens and policies. Both have local tokens. The ACL management APIs for both are very similar. I even ripped off Nomad's ACL bootstrap resetting procedure. There are a few key differences though.
Nomad requires token and policy replication where Consul only requires policy replication with token replication being opt-in. In Consul local tokens only work with token replication being enabled though.
All policies in Nomad are globally applicable. In Consul all policies are stored and replicated globally but can be scoped to a subset of the datacenters. This allows for more granular access management.
Unlike Nomad, Consul has legacy baggage in the form of the original ACL system. The ramifications of this are:
A server running the new system must still support other clients using the legacy system.
A client running the new system must be able to use the legacy RPCs when the servers in its datacenter are running the legacy system.
The primary ACL DC's servers running in legacy mode needs to be a gate that keeps everything else in the entire multi-DC cluster running in legacy mode.
So not only does this PR implement the new ACL system but has a legacy mode built in for when the cluster isn't ready for new ACLs. Also detecting that new ACLs can be used is automatic and requires no configuration on the part of administrators. This process is detailed more in the "Transitioning from Legacy to New ACL Mode" section below.
* Add -enable-local-script-checks options
These options allow for a finer control over when script checks are enabled by
giving the option to only allow them when they are declared from the local
file system.
* Add documentation for the new option
* Nitpick doc wording
* Initial draft of Sidecar Service and Managed Proxy deprecation docs
* Service definition deprecation notices and sidecar service
* gRPC and sidecar service config options; Deprecate managed proxy options
* Envoy Docs: Basic envoy command; envoy getting started/intro
* Remove change that snuck in
* Envoy custom config example
* Add agent/service API docs; deprecate proxy config endpoint
* Misc grep cleanup for managed proxies; capitalize Envoy
* Updates to getting started guide
* Add missing link
* Refactor Envoy guide into a separate guide and add bootstrap reference notes.
* Add limitations to Envoy docs; Highlight no fixes for known managed proxy issues on deprecation page; clarify snake cae stuff; Sidecar Service lifecycle
* Plumb xDS server and proxyxfg into the agent startup
* Add `consul connect envoy` command to allow running Envoy as a connect sidecar.
* Add test for help tabs; typos and style fixups from review
- A new endpoint `/v1/agent/service/:service_id` which is a generic way to look up the service for a single instance. The primary value here is that it:
- **supports hash-based blocking** and so;
- **replaces `/agent/connect/proxy/:proxy_id`** as the mechanism the built-in proxy uses to read its config.
- It's not proxy specific and so works for any service.
- It has a temporary shim to call through to the existing endpoint to preserve current managed proxy config defaulting behaviour until that is removed entirely (tested).
- The built-in proxy now uses the new endpoint exclusively for it's config
- The built-in proxy now has a `-sidecar-for` flag that allows the service ID of the _target_ service to be specified, on the condition that there is exactly one "sidecar" proxy (that is one that has `Proxy.DestinationServiceID` set) for the service registered.
- Several fixes for edge cases for SidecarService
- A fix for `Alias` checks - when running locally they didn't update their state until some external thing updated the target. If the target service has no checks registered as below, then the alias never made it past critical.
* Added new Config for SidecarService in ServiceDefinitions.
* WIP: all the code needed for SidecarService is written... none of it is tested other than config :). Need API updates too.
* Test coverage for the new sidecarServiceFromNodeService method.
* Test API registratrion with SidecarService
* Recursive Key Translation 🤦
* Add tests for nested sidecar defintion arrays to ensure they are translated correctly
* Use dedicated internal state rather than Service Meta for tracking sidecars for deregistration.
Add tests for deregistration.
* API struct for agent register. No other endpoint should be affected yet.
* Additional test cases to cover updates to API registrations
* Rename agent/proxy package to reflect that it is limited to managed proxy processes
Rationale: we have several other components of the agent that relate to Connect proxies for example the ProxyConfigManager component needed for Envoy work. Those things are pretty separate from the focus of this package so far which is only concerned with managing external proxy processes so it's nota good fit to put code for that in here, yet there is a naming clash if we have other packages related to proxy functionality that are not in the `agent/proxy` package.
Happy to bikeshed the name. I started by calling it `managedproxy` but `managedproxy.Manager` is especially unpleasant. `proxyprocess` seems good in that it's more specific about purpose but less clearly connected with the concept of "managed proxies". The names in use are cleaner though e.g. `proxyprocess.Manager`.
This rename was completed automatically using golang.org/x/tools/cmd/gomvpkg.
Depends on #4541
* Fix missed windows tagged files
* Add cache types for catalog/services and health/services and basic test that caching works
* Support non-blocking cache types with Cache-Control semantics.
* Update API docs to include caching info for every endpoint.
* Comment updates per PR feedback.
* Add note on caching to the 10,000 foot view on the architecture page to make the new data path more clear.
* Document prepared query staleness quirk and force all background requests to AllowStale so we can spread service discovery load across servers.
In a real agent the `cache` instance is alive until the agent shuts down so this is not a real leak in production, however in out test suite, every testAgent that is started and stops leaks goroutines that never get cleaned up which accumulate consuming CPU and memory through subsequent test in the `agent` package which doesn't help our test flakiness.
This adds a Close method that doesn't invalidate or clean up the cache, and still allows concurrent blocking queries to run (for up to 10 mins which might still affect tests). But at least it doesn't maintain them forever with background refresh and an expiry watcher routine.
It would be nice to cancel any outstanding blocking requests as well when we close but that requires much more invasive surgery right into our RPC protocol since we don't have a way to cancel requests currently.
Unscientifically this seems to make tests pass a bit quicker and more reliably locally but I can't really be sure of that!
If you provide an invalid HTTP configuration consul will still start again instead of failing. But if you do so the build-in proxy won't be able to start which you might need for connect.
Fixes: #4578
Prior to this fix if there was an error binding to ports for the DNS servers the error would be swallowed by the gated log writer and never output. This fix propagates the DNS server errors back to the shell with a multierror.
Fixes#4515
This just slightly refactors the logic to only attempt to set the serf wan reconnect timeout when the rest of the serf wan settings are configured - thus avoiding a segfault.
Also change how loadProxies works. Now it will load all persisted proxies into a map, then when loading config file proxies will look up the previous proxy token in that map.
- Dev mode assumed no persistence of services although proxy state is persisted which caused proxies to be killed on startup as their services were no longer registered. Fixed.
- Didn't snapshot the ProxyID which meant that proxies were adopted OK from snapshot but failed to restart if they died since there was no proxyID in the ENV on restart
- Dev mode with no persistence just kills all proxies on shutdown since it can't recover them later
- Naming things
This turns out to have a lot more subtelty than we accounted for. The test suite is especially prone to races now we can only poll the child and many extra levels of indirectoin are needed to correctly run daemon process without it becoming a Zombie.
I ran this test suite in a loop with parallel enabled to verify for races (-race doesn't find any as they are logical inter-process ones not actual data races). I made it through ~50 runs before hitting an error due to timing which is much better than before. I want to go back and see if we can do better though. Just getting this up.
Freddy