Re: chroot, Doctrine, ZendFrameWork

​Here some areas I've found chroot to be useful.

1 - I can have different versions of the same software (i.e. Node.js, Ruby,
PHP, etc) all installed on the same machine but separated out into
different chroot environments. This is GREAT for testing new versions or
being able to easily rollback if a deploy to a new version doesn't go as
expected.

2 - If you aren't sure how an install of software is going to affect your
system (i.e. something from perzl.org) then you can install it in a chroot
without if affecting other areas of PASE on the same machine.

3 - As mentioned by others, chroot also provides a very nice means for
allowing users/developers to log in and have the perception they are at the
root of the machine when in reality they are many levels deep in a "jailed"
environment.

4 - Some software (i.e. RubyGems, Node.js npm, etc) like to install things
globally. This is problematic on a machine where you might have multiple
developers or multiple environments (testing/staging/production), or both.
Using chroot you can have the software believe it is installing globally
(meaning you don't need to retrofit the install) even though it is local to
the chroot directory.

5 - chroot is great for things like CI (Continuous Integration) and CD
(Continuous Deployment). Simply put, when you do your unit testing (CI)
you can spin up a new environment that is *scripted* - meaning it is
created exactly the same each time without the chance of a developer
forgetting a step and creating a false positive in a unit test scenario.
Similar is true for automated CD - when a git commit happens you can do a
webhook on the git repo to automatically trigger a CI and if all unit tests
pass it will automatically deploy to production (CD) in a auto-generated
chroot space (again, one that is create the same *each* time). CI and CD
are things I am just now getting further into on IBM i with chroot.
​
​chroot on IBM i holds a lot of promise.

Aaron Bartell
litmis.com - Services for open source on IBM i