Issue 

How to upgrade from Zend Server for IBM i version 9 (or later) to the latest version of Zend Server for IBM i.

Upgrade Zend Server for IBM i from version 6 or later to versions up to 8.5.x

Environment

Currently running any version of Zend Server 9 on any supported version of IBM i.

Resolution

You can find the Zend Server for IBM i updates available here:

https://www.zend.com/en/products/server/downloads?token=e62dc97c43b55b8253e80e26b63a5806d0c74c805264ce03#IBM%20i

To download Zend Server and Zend Server updates, please go to zend.com and click the My Account link at the top of most pages.  If you are not already logged in, there are some options on the page.  Please use the one that says "IBMi Login" under the "MyZend Account" heading.  Login with your Zend login credentials.  Under the Account Summary tab, in the list headed "Downloads:", find the "Zend IBMi Server" link.  Click it to access the downloads page.

Select IBM i in the "Please select your platform" drop down box and choose the 'update from older versions' install file. The name of the downloaded installer file will indicate both the Zend Server version you will update to and the PHP version. For example:

ZendServer-9.1.3-php-7.1.16-IBM-i-Cum_PTF.zip

IMPORTANT: Make sure you get the file that includes "-Cum_PTF" at the end of the name.  You MUST NOT use the full installer to update Zend Server for IBM i, it must be the PTF upgrade installer.

Once you download and unzip the installation file, you will find a text document in the installation folder that explains how to apply the update as a PTF.

You should also download and install any Hotfixes or Updates that are available for the version of Zend Server and PHP you are upgrading to. These are found in the "Additional Downloads" section, if there are any.  Installation instructions are included in each download package.

During the installation, you will shut down Zend Server.  At that time, it is also good to verify that there are no additional locks on PHP from additional Apache instances or from php-cli:

Check for locks on PHP files prior to upgrading Zend Server for IBM i