In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "Learning about the differences between ceph-deploy and orchestration tools."

A block of code is set as follows:

nodes = [ 
 { :hostname => 'ansible', :ip => '192.168.0.40', :box => 'xenial64' 
 }, 
 { :hostname => 'mon1', :ip => '192.168.0.41', :box => 'xenial64' }, 
 { :hostname => 'mon2', :ip => '192.168.0.42', :box => 'xenial64' }, 
 { :hostname => 'mon3', :ip => '192.168.0.43', :box => 'xenial64' },

Any command-line input or output is written as follows:

vagrant plugin install vagrant-hostmanager

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "It has probed OSDs 1 and 2 for the data, which means that it didn’t find anything it needed. It wants to try and pol OSD 0, but it can’t because the OSD is down, hence the message as starting or marking this osd lost may let us proceed appeared."