Top Answers to Chef Interview Questions
First let us compare Chef with Puppet:
|API integration||Extended API||No extended API|
|Friendliness||Program friendly||System friendly|
|Configuring the server||Easy||Difficult|
Chef is a powerful configuration management tool and automation tool. It converts the infrastructure of the company into a structured format of code. Thanks to Chef you can develop scripts that can be used for automating the IT and business process.
The architecture of Chef can be broken down into the Chef Server, Chef Workstation and Chef Node.
- Chef Server – You can think of the Chef Server as the central store for that accumulates all the data that is necessary for configuring the nodes.
- Chef Node – The Chef Node can be thought of as a client responsible for sharing data across network and it is based on the chef-client architecture.
- Chef Workstation – The Chef Workstation can be thought of as the host for modifying the configuration data and cookbooks which is then forwarded to the Chef Server.
You can think of the Chef resource as a part of the infrastructure which is used for installing or running a service. Here we will discuss some of the important Chef resources:
- The desired state of a configuration item can be described
- To bring a certain item to a state you will know what are the steps involved
- You can choose the resources like package, template or services
- You can list the resource properties and other details needed
- You can group the resources into recipes for describing working configuration.
When you group resources, it gets converted into a Recipe and this describes the working configuration and the policy. Using the Recipe, you can get all that is necessary for configuring a specific system. So here we list some of the important functions of a Recipe:
- With the Chef Recipe you can install the software components
- You can manage the files and apps deployment
- You can execute the other recipes using one recipe.
We can think of the node as a physical server or a virtual machine that is a constituent of the Chef architecture. You can execute any resource with Chef.
When you group resources together what you get is a Recipe and this is useful in executing the configurations and policy. When you combine Recipes what you get is a Cookbook and this is easily manageable as compared to a Recipe.
When the action for a Chef Resource is not defined then it will automatically choose the Default action.
You can think of the Chef Repository as a collection of Cookbooks, roles, environments, data bags and more. It is possible to sync the Chef Repository with the Git and a Version Control System in order to improve the performance of it.
You need the SSL certificate for the initial configuration of the Chef and for creating the certificate and private keys in Nginx. This ensures that the right data can be accessed between the Chef Client and Chef Server.
The Signed Header is needed for the validation of the interaction between the Chef node, server and signed header authentication.
The run-list is needed for specifying the Recipes that are needed for running it and the order in which the Recipes will be executed.
Some of the advantages of run-list include:
- It ensures that the Recipes are running in the same order as specified
- The node on which the run-list is to be executed has to be specified
- It is transferred from the Workstation to Chef Server and the management console.
The starter kit is needed for creating the configuration files in Chef. It gives you the information for interacting with the server and defining the configuration file. You can easily download the starter kit and use it at the desired place on the workstation.
Here we give you the steps to follow for updating a Chef Cookbook:
- From the Workstation run the Knife SSH
- Run the SSH and Chef-client on the server directly
- You can use the Chef-client as a daemon for restarting the service as needed.
If you want to bootstrap in Chef, then you need the following information:
- The hostname or Public IP address of the node
- The user name and password for logging into a particular node
- Using keys as authentication rather than any login credentials.
The Test Kitchen in Chef will help you improve the development lifecycle and enables the Cookbooks on the server. You can also create different virtual machines in cloud or on-premise.