Errata

In this code sample
bundle type name(arguments)
{
promise_type:
class_expression:
promise
...
}

class_expression should end with "::" not only ":"

I think this is a syntax error, but I'm learning as I'm reading ;)

Note from the Author or Editor:
Thank you for the report, this is indeed a syntax error. I have fixed it.

cf-promises -v | grep Defined

Does not return any thing at all to me when i am using CFEngine Core 3.5.0b2.0887729

however i can check classes greping for "class" and i can see some hard, soft, and global classes

Note from the Author or Editor:
Thank you Walid, indeed the output changed in CFEngine 3.5.0. For the upcoming new edition of the book, I have changed the command to "grep classes", which works on all versions of CFEngine.

Thank you for your report.

The brief description of Puppet says that it is written in Python. According to the project website[1] Puppet is written in Ruby.

[1] http://docs.puppetlabs.com/guides/faq.html#why-is-puppet-written-in-ruby

Kind regards,
Grant

Note from the Author or Editor:
Confirmed and fixed. Thanks for catching it!

After creating the example motd cf-snippet it is advised to run "cf-agent.exe".

Suggestion:
- highlight differences between Windows and Unix Cfengine so the user is able to pick the correct executable
or
- ignore Windows completely / defer until later since the typical usage scenario is probably UNIX/Linux centric. Windows is kind of
an advanced topic.


additional suggestion: Rewrite the first example(s) so it/they may run without elevated privileges? Since the user is 'Learning CFEngine3' it may be nice to avoid accidentally breaking the system.

Note from the Author or Editor:
Good catch! Leftover from a time when I was editing the book on a Windows machine and copy-pasted the commands. Fixed.

"For integers, CFEngine sup-
ports .... the
prefixes K, M and G to represent powers of 2 (that is, 1024, etc.)"

In fact, from the example "i3" uses suffix, rather than prefixes as described here.

Note from the Author or Editor:
Thank you, I have fixed the text in the next edition of the book.

Found in epub version but that is not a selectable option.

In reference to CFEngine Nova "it also includes man convenience features, such as native support for databse" As of 3.3.0 "Database promises, which allow to maintain schema of MySQL and
PostgreSQL databases. Database promises are in "technical preview"
status: this promise type is subject to change in future." https://github.com/cfengine/core/blob/master/ChangeLog

Note from the Author or Editor:
I have updated this paragraph and other references throughout the book to reflect the recent changes.

The code example defines @(words) with the following list members:
"chair", "darwin", "table", "linux"

But the output of the cf-agent run that should be iterating over $(words) implies the following list members instead:
"darwin", "apple", "table", "linux"

This was confusing.

Note from the Author or Editor:
Thank you, will fix.

I believe "$(configfiles.files[sshdconfig])" should be
"$(configfiles.files[sshd])".

When I look at the bundle configfiles above, I see the "sshd" array used for setting the desired values - I don't see "sshdconfig" anywhere.

Note from the Author or Editor:
Yes, this is a mistake. Thanks for reporting it!

Hi,

with cfengine 3.4.4, I needed to change the files: section of configfiles5.cf to be

files:
"$($(id)[$(allfiles)]).original"
comment => "Ensure we have a backup of previous versions of $(allfiles)",
copy_from => backup_local_cp("$($(id)[$(allfiles)])");

e.g. $(allfiles) to be $($(id)[$(allfiles)]).

Thanks for your excellent book.

Note from the Author or Editor:
Of course, you are correct. I have fixed the examples. Thank you for your report!