The `ALLOC_INDEX` isn't guaranteed to be unique, and this has caused
some user confusion. The servers make a best-effort attempt to make
this value unique from 0 to count-1 but when you have canaries on the
task group, there are reused indexes because you have multiple job
versions running at the same time. If a user needs a unique number for
interpolating a value in your application, they can get this by
combining the job version and the alloc index.
Co-Authored-By: Michael Schurter <mschurter@hashicorp.com>
Currently `nomad monitor -node-id` will panic when a node-id does not
match any nodes, as there is no empty result bounds checking. Here we
return an error to the user when no nodes are found.
Copy the updated version of freeport (sdk/freeport), and tweak it for use
in Nomad tests. This means staying below port 10000 to avoid conflicts with
the lib/freeport that is still transitively used by the old version of
consul that we vendor. Also provide implementations to find ephemeral ports
of macOS and Windows environments.
Ports acquired through freeport are supposed to be returned to freeport,
which this change now also introduces. Many tests are modified to include
calls to a cleanup function for Server objects.
This should help quite a bit with some flakey tests, but not all of them.
Our port problems will not go away completely until we upgrade our vendor
version of consul. With Go modules, we'll probably do a 'replace' to swap
out other copies of freeport with the one now in 'nomad/helper/freeport'.
Operators commonly have docker logs aggregated using various tools and
don't need nomad to manage their docker logs. Worse, Nomad uses a
somewhat heavy docker api call to collect them and it seems to cause
problems when a client runs hundreds of log collections.
Here we add a knob to disable log aggregation completely for nomad.
When log collection is disabled, we avoid running logmon and
docker_logger for the docker tasks in this implementation.
The downside here is once disabled, `nomad logs ...` commands and API
no longer return logs and operators must corrolate alloc-ids with their
aggregated log info.
This is meant as a stop gap measure. Ideally, we'd follow up with at
least two changes:
First, we should optimize behavior when we can such that operators don't
need to disable docker log collection. Potentially by reverting to
using pre-0.9 syslog aggregation in linux environments, though with
different trade-offs.
Second, when/if logs are disabled, nomad logs endpoints should lookup
docker logs api on demand. This ensures that the cost of log collection
is paid sparingly.
There is an undocumented way of mapping a dynamically allocated port to the container. This is applicable in bridge networking ( necessary for consul connect enabled services ) to expose the service *directly*. This is needed when using upstream connect services, but you need to expose the service by normal means. By referencing the current documentation you need to use static ports in order to do so. Introduced in #6189 but undocumented
You'd think since golangci-lint embeds misspell we could use that,
but it fails to run if it finds no Go source files, which is the
case in our website/ directory that we want to check.
gometalinter has been deprecated, with golangci-lint as its spiritual
and recommended successor. Here we switch to using it with an equivalent
configuration, albeit with newer versions of some linters.
To maintain compatibility with existing settings, we have a couple of
things disabled here, specifically:
- tests
We have a lot of unused code in our tests that choke deadcode.
We should attempt to clean these up soon so that we can lint our
testcode.
- govet.check-shadowing = false
This breaks on redefining `err` which we do all over the nomad
codebase.
When trying to run this example, Nomad v0.10.2 raises the following error:
`Error getting job struct: Error parsing job file from example-ipv6.hcl: error parsing: At 33:22: Unknown token: 27:16 IDENT db`
Adding quotes around the port map `db` fixes the problem and the job works as expected.
Drew Bailey