Speed up client startup, by retrying more until the servers are known.
Currently, if client fingerprinting is fast and finishes before the
client connect to a server, node registration may be delayed by 15
seconds or so!
Ideally, we'd wait until the client discovers the servers and then retry
immediately, but that requires significant code changes.
Here, we simply retry the node registration request every second. That's
basically the equivalent of check if the client discovered servers every
second. Should be a cheap operation.
When testing this change on my local computer and where both servers and
clients are co-located, the time from startup till node registration
dropped from 34 seconds to 8 seconds!
When creating a TCP proxy bridge for Connect tasks, we are at the
mercy of either end for managing the connection state. For long
lived gRPC connections the proxy could reasonably expect to stay
open until the context was cancelled. For the HTTP connections used
by connect native tasks, we experience connection disconnects.
The proxy gets recreated as needed on follow up requests, however
we also emit a WARN log when the connection is broken. This PR
lowers the WARN to a TRACE, because these disconnects are to be
expected.
Ideally we would be able to proxy at the HTTP layer, however Consul
or the connect native task could be configured to expect mTLS, preventing
Nomad from MiTM the requests.
We also can't mange the proxy lifecycle more intelligently, because
we have no control over the HTTP client or server and how they wish
to manage connection state.
What we have now works, it's just noisy.
Fixes#10933
This PR implements a new "System Batch" scheduler type. Jobs can
make use of this new scheduler by setting their type to 'sysbatch'.
Like the name implies, sysbatch can be thought of as a hybrid between
system and batch jobs - it is for running short lived jobs intended to
run on every compatible node in the cluster.
As with batch jobs, sysbatch jobs can also be periodic and/or parameterized
dispatch jobs. A sysbatch job is considered complete when it has been run
on all compatible nodes until reaching a terminal state (success or failed
on retries).
Feasibility and preemption are governed the same as with system jobs. In
this PR, the update stanza is not yet supported. The update stanza is sill
limited in functionality for the underlying system scheduler, and is
not useful yet for sysbatch jobs. Further work in #4740 will improve
support for the update stanza and deployments.
Closes#2527
When the client launches, use a consistent read to fetch its own allocs,
but allow stale read afterwards as long as reads don't revert into older
state.
This change addresses an edge case affecting restarting client. When a
client restarts, it may fetch a stale data concerning its allocs: allocs
that have completed prior to the client shutdown may still have "run/running"
desired/client status, and have the client attempt to re-run again.
An alternative approach is to track the indices such that the client
set MinQueryIndex on the maximum index the client ever saw, or compare
received allocs against locally restored client state. Garbage
collection complicates this approach (local knowledge is not complete),
and the approach still risks starting "dead" allocations (e.g. the
allocation may have been placed when client just restarted and have
already been reschuled by the time the client started. This approach
here is effective against all kinds of stalness problems with small
overhead.
This PR fixes a bug where the underlying Envoy process of a Connect gateway
would consume a full core of CPU if there is more than one sidecar or gateway
in a group. The utilization was being caused by Consul injecting an envoy_ready_listener
on 127.0.0.1:8443, of which only one of the Envoys would be able to bind to.
The others would spin in a hot loop trying to bind the listener.
As a workaround, we now specify -address during the Envoy bootstrap config
step, which is how Consul maps this ready listener. Because there is already
the envoy_admin_listener, and we need to continue supporting running gateways
in host networking mode, and in those case we want to use the same port
value coming from the service.port field, we now bind the admin listener to
the 127.0.0.2 loop-back interface, and the ready listener takes 127.0.0.1.
This shouldn't make a difference in the 99.999% use case where envoy is
being run in its official docker container. Advanced users can reference
${NOMAD_ENVOY_ADMIN_ADDR_<service>} (as they 'ought to) if needed,
as well as the new variable ${NOMAD_ENVOY_READY_ADDR_<service>} for the
envoy_ready_listener.
Adds missing interpolation step to the `meta` blocks when building the task
environment. Also fixes incorrect parameter order in the test assertion and
adds diagnostics to the test.
There are bits of logic in callers of RemoveWorkload on group/task
cleanup hooks which call RemoveWorkload with the "Canary" version
of the workload, in case the alloc is marked as a Canary. This logic
triggers an extra sync with Consul, and also doesn't do the intended
behavior - for which no special casing is necessary anyway. When the
workload is marked for removal, all associated services and checks
will be removed regardless of the Canary status, because the service
and check IDs do not incorporate the canary-ness in the first place.
The only place where canary-ness matters is when updating a workload,
where we need to compute the hash of the services and checks to determine
whether they have been modified, the Canary flag of which is a part of
that.
Fixes#10842
recover
This code just seems incorrect. As it stands today it reports a
successful restore if RecoverTask fails and then DestroyTask succeeds.
This can result in a really annoying bug where it then calls RecoverTask
again, whereby it will probably get ErrTaskNotFound and call DestroyTask
once more.
I think the only reason this has not been noticed so far is because most
drivers like Docker will return Success, then nomad will call
RecoverTask, get an error (not found) and call DestroyTask again, and
get a ErrTasksNotFound err.
This PR makes it so that Nomad will automatically set the CONSUL_TLS_SERVER_NAME
environment variable for Connect native tasks running in bridge networking mode
where Consul has TLS enabled. Because of the use of a unix domain socket for
communicating with Consul when in bridge networking mode, the server name is
a file name instead of something compatible with the mTLS certificate Consul
will authenticate against. "localhost" is by default a compatible name, so Nomad
will set the environment variable to that.
Fixes#10804
Running the `client/allocrunner` tests fail to compile on macOS because the
CNI test file depends on the CNI network configurator, which is in a
Linux-only file.
When `network.mode = "bridge"`, we create a pause container in Docker with no
networking so that we have a process to hold the network namespace we create
in Nomad. The default `/etc/hosts` file of that pause container is then used
for all the Docker tasks that share that network namespace. Some applications
rely on this file being populated.
This changeset generates a `/etc/hosts` file and bind-mounts it to the
container when Nomad owns the network, so that the container's hostname has an
IP in the file as expected. The hosts file will include the entries added by
the Docker driver's `extra_hosts` field.
In this changeset, only the Docker task driver will take advantage of this
option, as the `exec`/`java` drivers currently copy the host's `/etc/hosts`
file and this can't be changed without breaking backwards compatibility. But
the fields are available in the task driver protobuf for community task
drivers to use if they'd like.
This updates `client.Ready()` so it returns once the client node got
registered at the servers. Previously, it returns when the
fingerprinters first batch completes, wtihout ensuring that the node is
stored in the Raft data. The tests may fail later when it with unknown
node errors later.
`client.Reedy()` seem to be only called in CSI and some client stats
now.
This class of bug, assuming client is registered without checking, is a
source of flakiness elsewhere. Other tests use other mechanisms for
checking node readiness, though not consistently.
This PR changes Nomad's wrapper around the Consul NamespaceAPI so that
it will detect if the Consul Namespaces feature is enabled before making
a request to the Namespaces API. Namespaces are not enabled in Consul OSS,
and require a suitable license to be used with Consul ENT.
Previously Nomad would check for a 404 status code when makeing a request
to the Namespaces API to "detect" if Consul OSS was being used. This does
not work for Consul ENT with Namespaces disabled, which returns a 500.
Now we avoid requesting the namespace API altogether if Consul is detected
to be the OSS sku, or if the Namespaces feature is not licensed. Since
Consul can be upgraded from OSS to ENT, or a new license applied, we cache
the value for 1 minute, refreshing on demand if expired.
Fixes https://github.com/hashicorp/nomad-enterprise/issues/575
Note that the ticket originally describes using attributes from https://github.com/hashicorp/nomad/issues/10688.
This turns out not to be possible due to a chicken-egg situation between
bootstrapping the agent and setting up the consul client. Also fun: the
Consul fingerprinter creates its own Consul client, because there is no
[currently] no way to pass the agent's client through the fingerprint factory.
Track usage of incoming streams on a connection. Connections without
reference counts get marked as unused and reaped in a periodic job.
This fixes a bug where `alloc exec` and `alloc fs` sessions get terminated
unexpectedly. Previously, when a client heartbeats switches between
servers, the pool connection reaper eventually identifies the connection
as unused and closes it even if it has an active exec/fs sessions.
Fixes#10579
This PR implements first-class support for Nomad running Consul
Connect Mesh Gateways. Mesh gateways enable services in the Connect
mesh to make cross-DC connections via gateways, where each datacenter
may not have full node interconnectivity.
Consul docs with more information:
https://www.consul.io/docs/connect/gateways/mesh-gateway
The following group level service block can be used to establish
a Connect mesh gateway.
service {
connect {
gateway {
mesh {
// no configuration
}
}
}
}
Services can make use of a mesh gateway by configuring so in their
upstream blocks, e.g.
service {
connect {
sidecar_service {
proxy {
upstreams {
destination_name = "<service>"
local_bind_port = <port>
datacenter = "<datacenter>"
mesh_gateway {
mode = "<mode>"
}
}
}
}
}
}
Typical use of a mesh gateway is to create a bridge between datacenters.
A mesh gateway should then be configured with a service port that is
mapped from a host_network configured on a WAN interface in Nomad agent
config, e.g.
client {
host_network "public" {
interface = "eth1"
}
}
Create a port mapping in the group.network block for use by the mesh
gateway service from the public host_network, e.g.
network {
mode = "bridge"
port "mesh_wan" {
host_network = "public"
}
}
Use this port label for the service.port of the mesh gateway, e.g.
service {
name = "mesh-gateway"
port = "mesh_wan"
connect {
gateway {
mesh {}
}
}
}
Currently Envoy is the only supported gateway implementation in Consul.
By default Nomad client will run the latest official Envoy docker image
supported by the local Consul agent. The Envoy task can be customized
by setting `meta.connect.gateway_image` in agent config or by setting
the `connect.sidecar_task` block.
Gateways require Consul 1.8.0+, enforced by the Nomad scheduler.
Closes#9446
When `nomad volume create` was introduced in Nomad 1.1.0, we changed the
volume spec to take a list of capabilities rather than a single capability, to
meet the requirements of the CSI spec. When a volume is registered via `nomad
volume register`, we should be using the same fields to validate the volume
with the controller plugin.
This PR adds new probes for detecting these new Consul related attributes:
Consul namespaces are a Consul enterprise feature that may be disabled depending
on the enterprise license associated with the Consul servers. Having this attribute
available will enable Nomad to properly decide whether to query the Consul Namespace
API.
Consul connect must be explicitly enabled before Connect APIs will work. Currently
Nomad only checks for a minimum Consul version. Having this attribute available will
enable Nomad to properly schedule Connect tasks only on nodes with a Consul agent that
has Connect enabled.
Consul connect requires the grpc port to be explicitly set before Connect APIs will work.
Currently Nomad only checks for a minimal Consul version. Having this attribute available
will enable Nomad to schedule Connect tasks only on nodes with a Consul agent that has
the grpc listener enabled.
This PR refactors the ConsulFingerprint implementation, breaking individual attributes
into individual functions to make testing them easier. This is in preparation for
additional extractors about to be added. Behavior should be otherwise unchanged.
It adds the attribute consul.sku, which can be used to differentiate between Consul
OSS vs Consul ENT.
Include the VolumeCapability.MountVolume data in
ControllerPublishVolume, CreateVolume, and ValidateVolumeCapabilities
RPCs sent to the CSI controller. The previous behavior was to only
include the MountVolume capability in the NodeStageVolume request, which
on some CSI implementations would be rejected since the Volume was not
originally provisioned with the specific mount capabilities requested.
Follow up to memory oversubscription - expose an env-var to indicate when memory oversubscription is enabled and what the limit is.
This will be helpful for setting hints to app for memory management.
Co-authored-by: Seth Hoenig <shoenig@hashicorp.com>
This commit ensures Nomad captures the task code more reliably even when the task is killed. This issue affect to `raw_exec` driver, as noted in https://github.com/hashicorp/nomad/issues/10430 .
We fix this issue by ensuring that the TaskRunner only calls `driver.WaitTask` once. The TaskRunner monitors the completion of the task by calling `driver.WaitTask` which should return the task exit code on completion. However, it also could return a "context canceled" error if the agent/executor is shutdown.
Previously, when a task is to be stopped, the killTask path makes two WaitTask calls, and the second returns "context canceled" occasionally because of a "race" in task shutting down and depending on driver, and how fast it shuts down after task completes.
By having a single WaitTask call and consistently waiting for the task, we ensure we capture the exit code reliably before the executor is shutdown or the contexts expired.
I opted to change the TaskRunner implementation to avoid changing the driver interface or requiring 3rd party drivers to update.
Additionally, the PR ensures that attempts to kill the task terminate when the task "naturally" dies. Without this change, if the task dies at the right moment, the `killTask` call may retry to kill an already-dead task for up to 5 minutes before giving up.
Add a new driver capability: RemoteTasks.
When a task is run by a driver with RemoteTasks set, its TaskHandle will
be propagated to the server in its allocation's TaskState. If the task
is replaced due to a down node or draining, its TaskHandle will be
propagated to its replacement allocation.
This allows tasks to be scheduled in remote systems whose lifecycles are
disconnected from the Nomad node's lifecycle.
See https://github.com/hashicorp/nomad-driver-ecs for an example ECS
remote task driver.
This PR wraps the use of the consul envoy bootstrap command in
an expoenential backoff closure, configured to timeout after 60
seconds. This is an increase over the current behavior of making
3 attempts over 6 seconds.
Should help with #10451
Similar to a bugfix made for the services hook, we need to always
set the script checks hook, in case a task is initially launched
without script checks, but then updated to include script checks.
The scipt checks hook is the thing that handles that new registration.
(cherry-picked from ent without _ent things)
This is part 2/4 of e2e tests for Consul Namespaces. Took a
first pass at what the parameterized tests can look like, but
only on the ENT side for this PR. Will continue to refactor
in the next PRs.
Also fixes 2 bugs:
- Config Entries registered by Nomad Server on job registration
were not getting Namespace set
- Group level script checks were not getting Namespace set
Those changes will need to be copied back to Nomad OSS.
Nomad OSS + no ACLs (previously, needs refactor)
Nomad ENT + no ACLs (this)
Nomad OSS + ACLs (todo)
Nomad ENT + ALCs (todo)
This PR introduces the /v1/search/fuzzy API endpoint, used for fuzzy
searching objects in Nomad. The fuzzy search endpoint routes requests
to the Nomad Server leader, which implements the Search.FuzzySearch RPC
method.
Requests to the fuzzy search API are based on the api.FuzzySearchRequest
object, e.g.
{
"Text": "ed",
"Context": "all"
}
Responses from the fuzzy search API are based on the api.FuzzySearchResponse
object, e.g.
{
"Index": 27,
"KnownLeader": true,
"LastContact": 0,
"Matches": {
"tasks": [
{
"ID": "redis",
"Scope": [
"default",
"example",
"cache"
]
}
],
"evals": [],
"deployment": [],
"volumes": [],
"scaling_policy": [],
"images": [
{
"ID": "redis:3.2",
"Scope": [
"default",
"example",
"cache",
"redis"
]
}
]
},
"Truncations": {
"volumes": false,
"scaling_policy": false,
"evals": false,
"deployment": false
}
}
The API is tunable using the new server.search stanza, e.g.
server {
search {
fuzzy_enabled = true
limit_query = 200
limit_results = 1000
min_term_length = 5
}
}
These values can be increased or decreased, so as to provide more
search results or to reduce load on the Nomad Server. The fuzzy search
API can be disabled entirely by setting `fuzzy_enabled` to `false`.
Mahmood Ali