Getting-Started-Guide not working as expected

[fraenku]

Nomad version

Nomad v1.3.0 (52e95d6)

Operating system and Environment details

NAME="CentOS Linux"
VERSION="7 (Core)"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="7"
PRETTY_NAME="CentOS Linux 7 (Core)"

Issue

I am following the getting-started section on https://learn.hashicorp.com/tutorials/nomad/get-started-run?in=nomad/get-started.
However when running the job example.nomad I have the error:
2022-05-20T11:54:41+02:00: Task Group "cache" (failed to place 1 allocation):
* Constraint "${attr.consul.version} semver >= 1.7.0": 1 nodes excluded by filter

Reproduction steps

• Follow the instruction-guide on https://learn.hashicorp.com/tutorials/nomad/get-started-run?in=nomad/get-started
• Execute nomad job run example.nomad

Expected Result

Having a successful deployment
Deployment "cd5820be" successful

Actual Result

The job is not deployed successfully due to the error
2022-05-20T11:54:41+02:00: Task Group "cache" (failed to place 1 allocation):
* Constraint "${attr.consul.version} semver >= 1.7.0": 1 nodes excluded by filter

Job file (if appropriate)

I think it is related to the service-part
service {
name = "redis-cache"
tags = ["global", "cache"]
port = "db"

  # The "check" stanza instructs Nomad to create a Consul health check for
  # this service. A sample check is provided here for your convenience;
  # uncomment it to enable it. The "check" stanza is documented in the
  # "service" stanza documentation.

  # check {
  #   name     = "alive"
  #   type     = "tcp"
  #   interval = "10s"
  #   timeout  = "2s"
  # }
}

After removing it, the job is deployed successfully.

Nomad Server logs (if appropriate)

Nomad Client logs (if appropriate)

[jrasell]

Hi @fraenku and thanks for raising this issue.

As you identified, Nomad v.1.3.0 introduced implicit constraints for task groups which utilise Consul for service discovery. The getting started guide does not run Consul which causes this problem.

The fix has already been merged into main via #13044 which changes the example job to use Nomad for service discovery. This will be available in an upcoming Nomad point release. I'l therefore close this issue out.

Please reach out if you experience additional problems!

[fraenku]

Thanks a lot for the fast response and quick update! I've seen that it has been fixed now with version 1.3.3 and that also redis has been updated to version 7.

However the documentation at https://learn.hashicorp.com/tutorials/nomad/get-started-jobs?in=nomad/get-started is still working with redis 3. At the next occasion this should also be updated.

[github-actions]

I'm going to lock this issue because it has been closed for 120 days ⏳. This helps our maintainers find and focus on the active issues.
If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.