Unable to detect openjdk java verion.

[Magicloud]

Nomad version

v0.9.4

Operating system and Environment details

CentOS 7

Issue

I cannot use driver.java.version constraint since it cannot get valid nodes.

Reproduction steps

Use following driver and contraint.

      driver = "java"
      constraint {
        attribute = "${driver.java.version}"
        operator  = ">="
        value     = "11.0.0"
      }

Without the contraint (comment the whole object), task running fine. With the contraint, I got

Constraint "${driver.java.version} >= 11.0.0" filtered 1 nodes

While java version is:

openjdk version "11.0.4" 2019-07-16 LTS
OpenJDK Runtime Environment 18.9 (build 11.0.4+11-LTS)
OpenJDK 64-Bit Server VM 18.9 (build 11.0.4+11-LTS, mixed mode, sharing)

[tgross]

Hello @Magicloud, thanks for your report!
I was able to partially reproduce what you’re seeing as follows:

$ docker run -it centos:7 /bin/bash
[root@b08656f9475b /]# yum install java-11-openjdk curl unzip
[root@b08656f9475b /]# curl -o nomad.zip https://releases.hashicorp.com/nomad/0.9.4/nomad_0.9.4_linux_amd64.zip
[root@b08656f9475b /]# unzip nomad.zip
[root@b08656f9475b /]# ./nomad agent -dev

and then submit the following job:

job "example" {
  datacenters = ["dc1"]

  type = "service"
  constraint {
    attribute = "${driver.java.version}"
    operator  = ">="
    value     = "11.0.0"
  }

  group "example" {
    task "example" {
      driver = "java"
      config {
        jar_path    = "local/hello.jar"
        jvm_options = ["-Xmx2048m", "-Xms256m"]
      }
    }
  }
}

which returned the following:

[root@b08656f9475b /]# ./nomad job run ./java.nomad
==> Monitoring evaluation "cda32b2b"
    Evaluation triggered by job "example"
    Evaluation status changed: "pending" -> "complete"
==> Evaluation "cda32b2b" finished with status "complete" but failed to place all allocations:
    Task Group "example" (failed to place 1 allocation):
      * Constraint "${driver.java.version} > 11.0.0" filtered 1 nodes
    Evaluation "5a36988b" waiting for additional capacity to place remainder

when I do java --version I get:

[root@b08656f9475b /]# java --version
openjdk 11.0.4 2019-07-16 LTS
OpenJDK Runtime Environment 18.9 (build 11.0.4+11-LTS)
OpenJDK 64-Bit Server VM 18.9 (build 11.0.4+11-LTS, mixed mode, sharing)

It looks like this version of the JDK doesn’t include " around the version and that’s throwing off the regex we use to parse the version; if I put this string into our unit tests for the java version parsing, I see the version doesn’t come back as 11.0.4 as I’d expect. But that version string isn’t quite what you’re showing in your report. Can you confirm whether you ran that java --version command on the client?

[Magicloud]

Yes, my bad. I pasted java version strings from wrong term. The CentOS one is like yours, no quotes.

[chriswhite199]

I have a similar issue to this - java driver is not detecting for the following:

openjdk version "11.0.3" 2019-04-16
OpenJDK Runtime Environment AdoptOpenJDK (build 11.0.3+7)
OpenJDK 64-Bit Server VM AdoptOpenJDK (build 11.0.3+7, mixed mode)

Client in the UI shows java detected: No.

Is there any debug logging i can enable to help diagnose?

Update: NVM, verbose node status shows my issue is that i'm not running nomad as root.

[github-actions]

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