General Information



Graphs and Logs

GIT and Storage



Trains Configuration

Trains Server Deployment

Trains Server Configuration

Trains Server Troubleshooting

Trains API

General Information

How do I know a new version came out?

Starting with Trains v0.9.3, Trains issues a new version release notification, which appears in the log and is output to the console, if a Python experiment script is run.

For example, when a new Trains Python Client Package version is available, the notification is:

TRAINS new package available: UPGRADE to vX.Y.Z is recommended!

When a new Trains Server version is available, the notification is:

TRAINS-SERVER new version available: upgrade to vX.Y is recommended!


How can I sort models by a certain metric?

Models are associated with the experiments that created them. To sort experiments by a specific metric, in the Trains Web-App, add a custom column in the experiments table and sort by that metric column.

For detailed instructions, see Customize the experiments table.

Can I store more information on the models?

Yes! For example, you can use the Task.set_model_label_enumeration() method to store class enumeration:

Task.current_task().set_model_label_enumeration( {"label": int(0), } )

For more information about Task class methods, see the Task Class reference page.

Can I store the model configuration file as well?

Yes! Use the Task.set_model_config() method:

Task.current_task().set_model_config("a very long text with the configuration file's content")

I am training multiple models at the same time, but I only see one of them. What happened?

Currently, in the experiment details panel, Trains shows only the last associated model. In Trains Web-App, on the Projects page, the Models tab shows all models.

This will be improved in a future version.

Can I log input and output models manually?

Yes! Use the InputModel.import_model method and Task.connect() methods to manually connect an input model. Use the Task.update_weights method to manually connect a model weights file.

input_model = InputModel.import_model(link_to_initial_model_file)


For more information about models, see InputModel and OutputModel classes.


I noticed I keep getting the message "warning: uncommitted code". What does it mean?

This message is only a warning. Trains not only detects your current repository and git commit, but also warns you if you are using uncommitted code. Trains does this because uncommitted code means this experiment will be difficult to reproduce. You can see uncommitted changes in the Trains Web-App, experiment details panel, EXECUTION tab.

I do not use argparse for hyperparameters. Do you have a solution?

Yes! Trains supports connecting hyperparameter dictionaries to experiments using the Task.connect() method.

For example, to log the hyperparameters learning_rate, batch_size, display_step, model_path, n_hidden_1, and n_hidden_2:

# Create a dictionary of parameters
parameters_dict = { 'learning_rate': 0.001, 'batch_size': 100, 'display_step': 1, 
    'model_path': "/tmp/model.ckpt", 'n_hidden_1': 256, 'n_hidden_2': 256 }

# Connect the dictionary to your TRAINS Task
parameters_dict = Task.current_task().connect(parameters_dict)

I noticed that all of my experiments appear as "Training" Are there other options?

Yes! When creating experiments and calling Task.init(), you can provide an experiment type. The currently supported types are Task.TaskTypes.training and Task.TaskTypes.testing. For example:

task = Task.init(project_name, task_name, Task.TaskTypes.testing)

Sometimes I see experiments as running when in fact they are not. What's going on?

Trains monitors your Python process. When the process exits in an orderly fashion, Trains closes the experiment. When the process crashes and terminates abnormally, the stop signal is sometimes missed. In this case, you can safely right click the experiment in the Web-App and abort it.

My code throws an exception, but my experiment status is not "Failed". What happened?

This issue was resolved in v0.9.2. Upgrade Trains by executing the following command:

pip install -U trains

When I run my experiment, I get an SSL Connection error CERTIFICATE_VERIFY_FAILED. Do you have a solution?

Your firewall may be preventing the connection. Try one of the following solutions:

  • Direct python "requests" to use the enterprise certificate file by setting the OS environment variables CURL_CA_BUNDLE or REQUESTS_CA_BUNDLE.
    For a detailed discussion of this topic, see https://stackoverflow.com/questions/48391750/disable-python-requests-ssl-validation-for-an-imported-module.
  • Disable certificate verification (for security reasons, this is not recommended):
    1. Upgrade Trains to the current version:
      pip install -U trains
    2. Create a new trains.conf configuration file (see a sample trains.conf), containing:
      api { verify_certificate = False }
    3. Copy the new trains.conf file to ~/trains.conf (on Windows: C:\Users\your_username\trains.conf)

How do I modify experiment names once they have been created??

An experiment's name is a user-controlled property which can be accessed via the Task.name variable. This allows you to use meaningful naming schemes for easily filtering and comparing of experiments.

For example, to distinguish between different experiments, you can append the task Id to the task name:

task = Task.init('examples', 'train')
task.name += ' {}'.format(task.id)

Or, append the Task Id post-execution:

tasks = Task.get_tasks(project_name='examples', task_name='train')
for t in tasks:
    t.name += ' {}'.format(task.id)

Another example is to append a specific hyperparameter and its value to each task's name:

tasks = Task.get_tasks(project_name='examples', task_name='my_automl_experiment')
for t in tasks:
    params = t.get_parameters()
    if 'my_secret_parameter' in params:
        t.name += ' my_secret_parameter={}'.format(params['my_secret_parameter'])

Use this experiment naming when creating automation pipelines with a naming convention, see our AutoML tutorial.

Graphs and Logs

The first log lines are missing from the experiment log tab. Where did they go?

Due to speed/optimization issues, we opted to display only the last several hundred log lines.

You can always downloaded the full log as a file using the Trains Web-App. In Trains Web-App, the experiment details panel, RESULTS tab, LOG sub-tab, use the download full log feature.

Can I create a graph comparing hyperparameters vs model accuracy?

Yes! You can manually create a plot with a single point X-axis for the hyperparameter value, and Y-Axis for the accuracy. For example:

number_layers = 10
accuracy = 0.95
    "performance", "accuracy", iteration=0, 
    mode='markers', scatter=[(number_layers, accuracy)])

Assuming the hyperparameter is number_layers with current value 10, and the accuracy for the trained model is 0.95. Then, the experiment comparison graph shows:

Another option is a histogram chart:

number_layers = 10
accuracy = 0.95
    "performance", "accuracy", iteration=0, labels=['accuracy'],
    values=[accuracy], xlabels=['number_layers %d' % number_layers])

I want to add more graphs, not just with TensorBoard. Is this supported?

Yes! The Logger module includes methods for explicit reporting. For examples of explicit reporting, see our Explicit Reporting tutorial, which includes a list of methods for explicit reporting.

GIT and Storage

Is there something Trains can do about uncommitted code running?

Yes! Trains stores the git diff as part of the experiment's information. You can view the git diff in the Trains Web-App experiment details panel EXECUTION tab.

I read there is a feature for centralized model storage. How do I use it?

When calling Task.init(), providing the output_uri parameter allows you to specify the location in which model snapshots will be stored.

For example, to store model snapshots in /mnt/shared/folder:

task = Task.init(project_name, task_name, output_uri="/mnt/shared/folder")

Trains will copy all stored snapshots into a subfolder under /mnt/shared/folder. The subfolder's name will contain the experiment's ID. If the experiment's ID is 6ea4f0b56d994320a713aeaf13a86d9d, the following folder will be used:


Trains supports other storage types for output_uri, including:

# AWS S3 bucket
task = Task.init(project_name, task_name, output_uri="s3://bucket-name/folder")
# Google Cloud Storage bucket
task = Task.init(project_name, task_name, output_uri="gs://bucket-name/folder")

To use Cloud storage with Trains, configure the storage credentials in your ~/trains.conf. For detailed information, see Trains Configuration Reference.

When using PyCharm to remotely debug a machine, the git repo is not detected. Do you have a solution?

Yes! Since this is such a common occurrence, we created a PyCharm plugin that allows a remote debugger to grab your local repository / commit ID. For detailed information about using our plugin, see the Trains PyCharm Plugin on the "Trains Plugins" page.


I am using Jupyter Notebook. Is this supported?

Yes! You can run Trains in Jupyter Notebooks using either of the following:

  • Option 1: Install Trains on your Jupyter Notebook host machine
  • Option 2: Install Trains in your Jupyter Notebook and connect using Trains credentials

Option 1: Install Trains on your Jupyter host machine

  1. Connect to your Juypter host machine.
  2. Install the Trains Python Client Package.
    pip install trains
  3. Run the Trains initialize wizard.
  4. In your Jupyter Notebook, you can now use Trains.

Option 2: Install Trains in your Jupyter Notebook

  1. In the Trains Web-App, Profile page, create credentials and copy your access key and secret key. These are required in the Step 3.
  2. Install the Trains Python Client Package.
    pip install trains
  3. Use the Task.set_credentials() method to specify the host, port, access key and secret key (see step 1).
    # Set your credentials using the trains apiserver URI and port, access_key, and secret_key.
    Task.set_credentials(host='http://localhost:8008',key='<access_key>', secret='<secret_key>')

    Host is the API server

    host is the API server (default port 8008), not the web server (default port 8080).

  4. You can now use Trains.
    # create a task and start training
    task = Task.init('juptyer project', 'my notebook')

Git is not well-supported in Jupyter, so we just gave up on committing our code. Do you have a solution?

Yes! Use our Trains Jupyter Plugin. This plugin allows you to commit your notebook directly from Jupyter. It also saves the Python version of your code and creates an updated requirements.txt so you know which packages you were using.


Can I use Trains with scikit-learn?

Yes! scikit-learn is supported. Everything you do is logged. Models are automatically logged when stored using joblib.

For example:

# from sklearn.externals import joblib
import joblib
joblib.dump(model, 'model.pkl')
loaded_model = joblib.load('model.pkl')

Trains Configuration

How can I change the location of Trains configuration file?

To override the default configuration file location, set the TRAINS_CONFIG_FILE OS environment variable.

For example:

export TRAINS_CONFIG_FILE="/home/user/mytrains.conf"

How can I override Trains credentials from the OS environment?

To override the configuration file / defaults, set the following OS environment variables:

export TRAINS_API_ACCESS_KEY="key_here"
export TRAINS_API_SECRET_KEY="secret_here"
export TRAINS_API_HOST="http://localhost:8008"

How can I track OS environment variables with experiments?

Set the OS environment variable TRAINS_LOG_ENVIRONMENT with the variables you need track, either:

  • All environment variables:
  • Specific environment variables, for example, log PWD and PYTHONPATH:
  • No environment variables:

Trains Server Deployment

How do I deploy Trains Server on stand-alone Linux Ubuntu or Mac OS X systems?

For detailed instructions, see Deploying Trains Server: Linux or Mac OS X in the "Deploying Trains" section.

How do I deploy Trains Server on Windows 10?

For detailed instructions, see Deploying Trains Server: Windows 10 in the "Deploying Trains" section.

How do I restart Trains Server?

For detailed instructions, see Restarting Trains Server in the "Deploying Trains" section.

Can I deploy Trains Server on Kubernetes clusters?

Yes! Trains Server supports Kubernetes. For detailed instructions, see Deploying Trains Server: Kubernetes in the "Deploying Trains" section.

Can I create a Helm Chart for Trains Server Kubernetes deployment?

Yes! You can create a Helm Chart of Trains Server Kubernetes deployment.

For detailed instructions, see Deploying Trains Server: Kubernetes Using Helm in the "Deploying Trains" section.

Trains Server Configuration

How do I configure Trains Server for sub-domains and load balancers?

For detailed instructions, see Configuring Sub-domains and load balancers on the "Configuring Trains Server" page.

Can I add web login authentication to Trains Server?

By default, anyone can login to the Trains Server Web-App. You can configure the Trains Server to allow only a specific set of users to access the system.

For detailed instructions, see Configuring Web Login Authentication on the "Configuring Trains Server" page. in the "Deploying Trains" section.

Can I modify a non-responsive task settings?

The non-responsive experiment watchdog monitors experiments that were not updated for a specified period of time and marks them as aborted. The watchdog is always active.

You can modify the following settings for the watchdog:

  • The time threshold (in seconds) of task inactivity (default value is 7200 seconds which is 2 hours).
  • The time interval (in seconds) between watchdog cycles.

For detailed instructions, see Modifying non-responsive Task watchdog settings on the "Configuring Trains Server" page.

Trains Server Troubleshooting

How do I fix Docker upgrade errors?

To resolve the Docker error

... The container name "/trains-???" is already in use by ...

try removing deprecated images:

$ docker rm -f $(docker ps -a -q)

Why is web login authentication not working?

A port conflict between the Trains Server MongoDB and / or Elastic instances, and other instances running on your system may prevent web login authentication from working correctly.

Trains Server uses the following default ports which may be in conflict with other instances:

  • MongoDB port 27017
  • Elastic port 9200

You can check for port conflicts in the logs in /opt/trains/log.

If a port conflict occurs, change the MongoDB and / or Elastic ports in the docker-compose.yml, and then run the Docker compose commands to restart the Trains Server instance.

To change the MongoDB and / or Elastic ports for Trains Server:

  1. Edit the docker-compose.yml file.
  2. In the services/trainsserver/environment section, add the following environment variable(s):
    • For MongoDB:
      MONGODB_SERVICE_PORT: <new-mongodb-port>
    • For Elastic:
      ELASTIC_SERVICE_PORT: <new-elasticsearch-port>
    • For example:
  3. For MongoDB, in the services/mongo/ports section, expose the new MongoDB port:
    For example:
  4. For Elastic, in the services/elasticsearch/ports section, expose the new Elastic port:
    For example:
  5. Restart Trains Server, see Restarting Trains Server.

Trains API

How can I use the Trains API to fetch data?

To fetch data using the Trains API, create an authenticated session and send requests for data using the Trains API services and methods. The responses to the requests contain your data.

For example, to get the metrics for an experiment and print metrics as a histogram:

  1. Start an authenticated session.
  2. Send a request for all projects named examples using the projects service GetAllRequest method.
  3. From the response, get the Ids of all those projects named examples.
  4. Send a request for all experiments (tasks) with those project Ids using the tasks service GetAllRequest method.
  5. From the response, get the data for the experiment (task) Id 11 and print the experiment name.
  6. Send a request for a metrics histogram for experiment (task) Id 11 using the events service ScalarMetricsIterHistogramRequest method and print the histogram.
# Import Session from the trains backend_api
from trains.backend_api import Session
# Import the services for tasks, events, and projects
from trains.backend_api.services import tasks, events, projects

# Create an authenticated session
session = Session()

# Get projects matching the project name 'examples'
res = session.send(projects.GetAllRequest(name='examples'))
# Get all the project Ids matching the project name 'examples"
projects_id = [p.id for p in res.response.projects]
print('project ids: {}'.format(projects_id))

# Get all the experiments/tasks
res = session.send(tasks.GetAllRequest(project=projects_id))

# Do your work
# For example, get the experiment whose Id is '11'
task = res.response.tasks[11]
print('task name: {}'.format(task.name))

# For example, for experiment Id '11', get the experiment metric values
res = session.send(events.ScalarMetricsIterHistogramRequest(
scalars = res.response_data
print('scalars {}'.format(scalars))