interface has 3 implementations:
1. local for blocking and moving data locally
2. remote for blocking and moving data from another node
3. noop for allocs that don't need to block
Fixes#2478#2474#1995#2294
The new client only handles agent and task service advertisement. Server
discovery is mostly unchanged.
The Nomad client agent now handles all Consul operations instead of the
executor handling task related operations. When upgrading from an
earlier version of Nomad existing executors will be told to deregister
from Consul so that the Nomad agent can re-register the task's services
and checks.
Drivers - other than qemu - now support an Exec method for executing
abritrary commands in a task's environment. This is used to implement
script checks.
Interfaces are used extensively to avoid interacting with Consul in
tests that don't assert any Consul related behavior.
This PR takes the host ID and runs it through a hash so that it is well
distributed. This makes it so that machines that report similar host IDs
are easily distinguished.
Instances of similar IDs occur on EC2 where the ID is prefixed and on
motherboards created in the same batch.
Fixes https://github.com/hashicorp/nomad/issues/2534
This PR adds tracking to when a task starts and finishes and the logs
API takes advantage of this and returns better errors when asking for
logs that do not exist.
This PR fixes two issues:
* Folder permissions in -dev mode were incorrect and not suitable for
running as a particular user.
* Was not setting the group membership properly for the launched
process.
Fixes https://github.com/hashicorp/nomad/issues/2160
This PR introduces a parallelism limit during garbage collection. This
is used to avoid large resource usage spikes if garbage collecting many
allocations at once.
This PR adds the following metrics to the client:
client.allocations.migrating
client.allocations.blocked
client.allocations.pending
client.allocations.running
client.allocations.terminal
Also adds some missing fields to the API version of the evaluation.
This PR fixes our vet script and fixes all the missed vet changes.
It also fixes pointers being printed in `nomad stop <job>` and `nomad
node-status <node>`.
This PR makes GetAllocs use a blocking query as well as adding a sanity
check to the clients watchAllocation code to ensure it gets the correct
allocations.
This PR fixes https://github.com/hashicorp/nomad/issues/2119 and
https://github.com/hashicorp/nomad/issues/2153.
The issue was that the client was talking to two different servers, one
to check which allocations to pull and the other to pull those
allocations. However the latter call was not with a blocking query and
thus the client would not retreive the allocations it requested.
The logging has been improved to make the problem more clear as well.
Client.Shutdown holds the allocLock when destroying alloc runners in dev
mode.
Client.updateAllocStatus can be called during AllocRunner shutdown and
calls getAllocRunners which tries to acquire allocLock.RLock. This
deadlocks since Client.Shutdown already has the write lock.
Switching Client.Shutdown to use getAllocRunners and not hold a lock
during AllocRunner shutdown is the solution.
The Driver.Prestart method currently does very little but lays the
foundation for where lifecycle plugins can interleave execution _after_
task environment setup but _before_ the task starts.
Currently Prestart does two things:
* Any driver specific task environment building
* Download Docker images
This change also attaches a TaskEvent emitter to Drivers, so they can
emit events during task initialization.
This PR disallows stale queries when deriving a Vault token. Allowing
stale queries could result in the allocation not existing on the server
that is servicing the request.
Many thanks to @iverberk for the original PR (#1609), but we ended up
not wanting to ship this implementation with 0.5.
We'll come back to it after 0.5 and hopefully find a way to leverage
filesystem accounting and quotas, so we can skip the expensive polling.
* In -dev mode, `ioutil.TempDir` is used for the alloc and state
directories.
* `TempDir` uses `$TMPDIR`, which os OS X contains a per user
directory which is under `/var/folder`.
* `/var` is actually a symlink to `/private/var`
* Docker For Mac validates the directories that are passed to bind and on
OS X. That whitelist contains `/private`, but not `/var`. It does not
expand the path, and so any paths in `$TMPDIR` fail the whitelist check.
And thusly, by expanding the alloc/state directories the value passed
for binding does contain `/private` and Docker For Mac is happy.
* Added the alloc dir move
* Moving allocdirs when starting allocations
* Added the migrate flag to ephemeral disk
* Stopping migration if the allocation doesn't need migration any more
* Added the GetAllocDir method
* refactored code
* Added a test for alloc runner
* Incorporated review comments
Remove use of periodic consul handlers in the client and just use
goroutines. Consul Discovery is now triggered with a chan instead of
using a timer and deadline to trigger.
Once discovery is complete a chan is ticked so all goroutines waiting
for servers will run.
Should speed up bootstraping and recovery while decreasing spinning on
timers.
rpcproxy is refactored into serverlist which prioritizes good servers
over servers in a remote DC or who have had a failure.
Registration, heartbeating, and alloc status updating will retry faster
when new servers are discovered.
Consul discovery will be retried more quickly when no servers are
available (eg on startup or an outage).
Per discussion, we want to be aggressive about fanning out vs possibly
fixating on only local DCs. With RPC forwarding in place, a random walk
may be less optimal from a network latency perspective, but it is guaranteed
to eventually result in a converged state because all DCs are candidates
during the bootstrapping process.
Client: Search limit increased from 4 random DCs to 8 random DCs, plus nearest.
Server: Search factor increased from 3 to 5 times the bootstrap_expect.
This should allow for faster convergence in large environments (e.g.
sub-5min for 10K Consul DCs).
It's possible that a Nomad Client is heartbeating with a Nomad server that
has become issolated from the quorum of Nomad Servers. When 3x the
heartbeatTTL has been exceeded, append the Consul server list to the primary
primary server list. When the next RPCProxy rebalance occurs, there is a
chance one of the servers discovered from Consul will be in the majority.
When client reattaches to a Nomad Server in the majority, it will include
a heartbeat and will reset the TTLs *AND* will clear the primary server list
to include only values from the heartbeat.
This has been done to allow the Server and Client to reuse the same
Syncer because the Agent may be running Client, Server, or both
simultaneously and we only want one Syncer object alive in the agent.
I *KNEW* I should have done this when I wrote it, but didn't want to
go back and audit the handlers to include the appropriate return
handling, but now that the code is taking shape, make this change.
In addition to the API changing, consul.Syncer can now be signaled
to shutdown via the Shutdown() method, which will call the Run()'ing
sync task to exit gracefully.
While breaking the API within this PR, break out the individual
arguments to RefreshServerLists. The servers parameter is reusing
`structs.NodeServerInfo` for the time being, but this can be revisited
if the needs of the strucutre diverge in the future.
With an over abundance of caution, preevnt future copy/pasta by
using the right locks when bootstrapping a Client. Strictly speaking
this is not necessary, but it makes explicit the locking semantics
and guards against future concurrent or parallel initialization.
When an agent is running a server, the list of servers includes the
Raft peers. When the agent is running a client (which is always the
case?), include a list of the servers found in the Client's RpcProxy.
Dedupe and provide a unique list back to the caller.
Reduce future confusion by introducing a minor version that is gossiped out
via the `mvn` Serf tag (Minor Version Number, `vsn` is already being used for
to communicate `Major Version Number`).
Background: hashicorp/consul/issues/1346#issuecomment-151663152
In order to give clients a fighting chance to talk to the right port,
differentiate RPC services from HTTP services by registering two
services with different tags. This yields
`rpc.nomad-server.service.consul` and
`http.nomad-server.service.consul` which is immensely more useful to
clients attempting to bootstrap their world.
