Troubleshooting Salt Cloud

This page describes various steps for troubleshooting problems that may arise while using Salt Cloud.

Virtual Machines Are Created, But Do Not Respond

Are TCP ports 4505 and 4506 open on the master? This is easy to overlook on new masters. Information on how to open firewall ports on various platforms can be found here.

Generic Troubleshooting Steps

This section describes a set of instructions that are useful to a large number of situations, and are likely to solve most issues that arise.

Debug Mode

Frequently, running Salt Cloud in debug mode will reveal information about a deployment which would otherwise not be obvious:

salt-cloud -p myprofile myinstance -l debug

Keep in mind that a number of messages will appear that look at first like errors, but are in fact intended to give developers factual information to assist in debugging. A number of messages that appear will be for cloud providers that you do not have configured; in these cases, the message usually is intended to confirm that they are not configured.

Salt Bootstrap

By default, Salt Cloud uses the Salt Bootstrap script to provision instances:

This script is packaged with Salt Cloud, but may be updated without updating the Salt package:

salt-cloud -u

The Bootstrap Log

If the default deploy script was used, there should be a file in the /tmp/ directory called bootstrap-salt.log. This file contains the full output from the deployment, including any errors that may have occurred.

Keeping Temp Files

Salt Cloud uploads minion-specific files to instances once they are available via SSH, and then executes a deploy script to put them into the correct place and install Salt. The --keep-tmp option will instruct Salt Cloud not to remove those files when finished with them, so that the user may inspect them for problems:

salt-cloud -p myprofile myinstance --keep-tmp

By default, Salt Cloud will create a directory on the target instance called /tmp/.saltcloud/. This directory should be owned by the user that is to execute the deploy script, and should have permissions of 0700.

Most cloud hosts are configured to use root as the default initial user for deployment, and as such, this directory and all files in it should be owned by the root user.

The /tmp/.saltcloud/ directory should the following files:

  • A script. This script should have permissions of 0755.
  • A .pem and .pub key named after the minion. The .pem file should have permissions of 0600. Ensure that the .pem and .pub files have been properly copied to the /etc/salt/pki/minion/ directory.
  • A file called minion. This file should have been copied to the /etc/salt/ directory.
  • Optionally, a file called grains. This file, if present, should have been copied to the /etc/salt/ directory.

Unprivileged Primary Users

Some cloud hosts, most notably EC2, are configured with a different primary user. Some common examples are ec2-user, ubuntu, fedora, and bitnami. In these cases, the /tmp/.saltcloud/ directory and all files in it should be owned by this user.

Some cloud hosts, such as EC2, are configured to not require these users to provide a password when using the sudo command. Because it is more secure to require sudo users to provide a password, other hosts are configured that way.

If this instance is required to provide a password, it needs to be configured in Salt Cloud. A password for sudo to use may be added to either the provider configuration or the profile configuration:

sudo_password: mypassword

/tmp/ is Mounted as noexec

It is more secure to mount the /tmp/ directory with a noexec option. This is uncommon on most cloud hosts, but very common in private environments. To see if the /tmp/ directory is mounted this way, run the following command:

mount | grep tmp

The if the output of this command includes a line that looks like this, then the /tmp/ directory is mounted as noexec:

tmpfs on /tmp type tmpfs (rw,noexec)

If this is the case, then the deploy_command will need to be changed in order to run the deploy script through the sh command, rather than trying to execute it directly. This may be specified in either the provider or the profile config:

deploy_command: sh /tmp/.saltcloud/

Please note that by default, Salt Cloud will place its files in a directory called /tmp/.saltcloud/. This may be also be changed in the provider or profile configuration:

tmp_dir: /tmp/.saltcloud/

If this directory is changed, then the deploy_command need to be changed in order to reflect the tmp_dir configuration.

Executing the Deploy Script Manually

If all of the files needed for deployment were successfully uploaded to the correct locations, and contain the correct permissions and ownerships, the deploy script may be executed manually in order to check for other issues:

cd /tmp/.saltcloud/