» Upgrading Specific Versions

The upgrading page covers the details of doing a standard upgrade. However, specific versions of Nomad may have more details provided for their upgrades as a result of new features or changed behavior. This page is used to document those details separately from the standard upgrade flow.

» Nomad 0.6.0

» Default advertise address changes

When no advertise address was specified and Nomad's bind_addr was loopback or 0.0.0.0, Nomad attempted to resolve the local hostname to use as an advertise address.

Many hosts cannot properly resolve their hostname, so Nomad 0.6 defaults advertise to the first private IP on the host (e.g. 10.1.2.3).

If you manually configure advertise addresses no changes are necessary.

» Nomad 0.5.5

» Docker load changes

Nomad 0.5.5 has a backward incompatible change in the docker driver's configuration. Prior to 0.5.5 the load configuration option accepted a list images to load, in 0.5.5 it has been changed to a single string. No functionality was changed. Even if more than one item was specified prior to 0.5.5 only the first item was used.

To do a zero-downtime deploy with jobs that use the load option:

  • Upgrade servers to version 0.5.5 or later.

  • Deploy new client nodes on the same version as the servers.

  • Resubmit jobs with the load option fixed and a constraint to only run on version 0.5.5 or later:

    constraint {
      attribute = "${attr.nomad.version}"
      operator  = "version"
      value     = ">= 0.5.5"
    }
  • Drain and shutdown old client nodes.

» Validation changes

Due to internal job serialization and validation changes you may run into issues using 0.5.5 command line tools such as nomad run and nomad validate with 0.5.4 or earlier agents.

It is recommended you upgrade agents before or alongside your command line tools.

» Nomad 0.4.0

Nomad 0.4.0 has backward incompatible changes in the logic for Consul deregistration. When a Task which was started by Nomad v0.3.x is uncleanly shut down, the Nomad 0.4 Client will no longer clean up any stale services. If an in-place upgrade of the Nomad client to 0.4 prevents the Task from gracefully shutting down and deregistering its Consul-registered services, the Nomad Client will not clean up the remaining Consul services registered with the 0.3 Executor.

We recommend draining a node before upgrading to 0.4.0 and then re-enabling the node once the upgrade is complete.

» Nomad 0.3.1

Nomad 0.3.1 removes artifact downloading from driver configurations and places them as a first class element of the task. As such, jobs will have to be rewritten in the proper format and resubmitted to Nomad. Nomad clients will properly re-attach to existing tasks but job definitions must be updated before they can be dispatched to clients running 0.3.1.

» Nomad 0.3.0

Nomad 0.3.0 has made several substantial changes to job files included a new log block and variable interpretation syntax (${var}), a modified restart policy syntax, and minimum resources for tasks as well as validation. These changes require a slight change to the default upgrade flow.

After upgrading the version of the servers, all previously submitted jobs must be resubmitted with the updated job syntax using a Nomad 0.3.0 binary.

  • All instances of $var must be converted to the new syntax of ${var}

  • All tasks must provide their required resources for CPU, memory and disk as well as required network usage if ports are required by the task.

  • Restart policies must be updated to indicate whether it is desired for the task to restart on failure or to fail using mode = "delay" or mode = "fail" respectively.

  • Service names that include periods will fail validation. To fix, remove any periods from the service name before running the job.

After updating the Servers and job files, Nomad Clients can be upgraded by first draining the node so no tasks are running on it. This can be verified by running nomad node-status <node-id> and verify there are no tasks in the running state. Once that is done the client can be killed, the data_dir should be deleted and then Nomad 0.3.0 can be launched.