This commit is an initial (read: janky) approach to forwarding state
from an allocrunner hook to a taskrunner using a similar `hookResources`
approach that tr's use internally.
It should eventually probably be replaced with something a little bit
more message based, but for things that only come from pre-run hooks,
and don't change, it's probably fine for now.
This commit introduces the first stage of volume mounting for an
allocation. The csimanager.VolumeMounter interface manages the blocking
and actual minutia of the CSI implementation allowing this hook to do
the minimal work of volume retrieval and creating mount info.
In the future the `CSIVolume.Get` request should be replaced by
`CSIVolume.Claim(Batch?)` to minimize the number of RPCs and to handle
external triggering of a ControllerPublishVolume request as required.
We also need to ensure that if pre-run hooks fail, we still get a full
unwinding of any publish and staged volumes to ensure that there are no hanging
references to volumes. That is not handled in this commit.
As part of introducing support for CSI, AllocRunner hooks need to be
able to communicate with Nomad Servers for validation of and interaction
with storage volumes. Here we create a small RPCer interface and pass
the client (rpc client) to the AR in preparation for making these RPCs.
This changeset implements the minimal structs on the client-side we
need to compile the work-in-progress implementation of the
server-to-controller RPCs. It doesn't include implementing the
`ClientCSI.DettachVolume` RPC on the client.
When providing paths to plugins, the path needs to be in the scope of
the plugins container, rather than that of the host.
Here we enable that by providing the mount point through the plugin
registration and then use it when constructing request target paths.
This commit introduces support for staging volumes when a plugin
implements the STAGE_UNSTAGE_VOLUME capability.
See the following for further reference material:
4731db0e0b/spec.md (nodestagevolume)
This commit adds helpers that create and validate the staging directory
for a given volume. It is currently missing usage options as the
interfaces are not yet in place for those.
The staging directory is only required when a volume has the
STAGE_UNSTAGE Volume capability and has to live within the plugin root
as the plugin needs to be able to create mounts inside it from within
the container.
This changeset is some pre-requisite boilerplate that is required for
introducing CSI volume management for client nodes.
It extracts out fingerprinting logic from the csi instance manager.
This change is to facilitate reusing the csimanager to also manage the
node-local CSI functionality, as it is the easiest place for us to
guaruntee health checking and to provide additional visibility into the
running operations through the fingerprinter mechanism and goroutine.
It also introduces the VolumeMounter interface that will be used to
manage staging/publishing unstaging/unpublishing of volumes on the host.
This commit introduces a new set of endpoints to a Nomad Client:
ClientCSI.
ClientCSI is responsible for mediating requests from a Nomad Server to
a CSI Plugin running on a Nomad Client. It should only really be used to
make controller RPCs.
This changeset implements the initial registration and fingerprinting
of CSI Plugins as part of #5378. At a high level, it introduces the
following:
* A `csi_plugin` stanza as part of a Nomad task configuration, to
allow a task to expose that it is a plugin.
* A new task runner hook: `csi_plugin_supervisor`. This hook does two
things. When the `csi_plugin` stanza is detected, it will
automatically configure the plugin task to receive bidirectional
mounts to the CSI intermediary directory. At runtime, it will then
perform an initial heartbeat of the plugin and handle submitting it to
the new `dynamicplugins.Registry` for further use by the client, and
then run a lightweight heartbeat loop that will emit task events
when health changes.
* The `dynamicplugins.Registry` for handling plugins that run
as Nomad tasks, in contrast to the existing catalog that requires
`go-plugin` type plugins and to know the plugin configuration in
advance.
* The `csimanager` which fingerprints CSI plugins, in a similar way to
`drivermanager` and `devicemanager`. It currently only fingerprints
the NodeID from the plugin, and assumes that all plugins are
monolithic.
Missing features
* We do not use the live updates of the `dynamicplugin` registry in
the `csimanager` yet.
* We do not deregister the plugins from the client when they shutdown
yet, they just become indefinitely marked as unhealthy. This is
deliberate until we figure out how we should manage deploying new
versions of plugins/transitioning them.
allow oss to parse sink duration
clean up audit sink parsing
ent eventer config reload
fix typo
SetEnabled to eventer interface
client acl test
rm dead code
fix failing test
In service jobs, lifecycles non-sidecar task tweak health logic a bit:
they may terminate successfully without impacting alloc health, but fail
the alloc if they fail.
Sidecars should be treated just like a normal task.
Fixes a bug where an allocation is considered healthy if some of the
tasks are being restarted and as such, their checks aren't tracked by
consul agent client.
Here, we fix the immediate case by ensuring that an alloc is healthy
only if tasks are running and the registered checks at the time are
healthy.
Previously, health tracker tracked task "health" independently from
checks and leads to problems when a task restarts. Consider the
following series of events:
1. all tasks start running -> `tracker.tasksHealthy` is true
2. one task has unhealthy checks and get restarted
3. remaining checks are healthy -> `tracker.checksHealthy` is true
4. propagate health status now that `tracker.tasksHealthy` and
`tracker.checksHealthy`.
This change ensures that we accurately use the latest status of tasks
and checks regardless of their status changes.
Also, ensures that we only consider check health after tasks are
considered healthy, otherwise we risk trusting incomplete checks.
This approach accomodates task dependencies well. Service jobs can have
prestart short-lived tasks that will terminate before main process runs.
These dead tasks that complete successfully will not negate health
status.
