Multiple Releases

From DLXS Documentation

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Revision as of 19:15, 9 August 2007

Contents 1 Introduction 2 Installing and configuring two DLXS releases 2.1 Two DLXSROOT values and two databases 3 Pointing two different DLXS releases at the same data

Introduction

You might want to have two different releases of DLXS Middleware running at the same time. For example, to keep a past release running in production while installing, configuring and migrating your local UI or code changes to a new release.

Given these two installations, you may or may not want to have both releases pointing to the same image files and indexed XML data.

Installing and configuring two DLXS releases

Two DLXSROOT values and two databases

Suppose you already have a pervious DLXS release and database installed.

1. Install the new release under a new DLXSROOT directory. Give the installer program (Installer.pl) this directory when you install.
2. Create another MySQL database for the new install with a different name, e.g. dlxs_v6 as we covered in Installing and Upgrading the Database). Answer the installer prompt for dabase name with the database name for the new installation.</small>
3. Configure another virtual host under your web server and point its DLXSROOT to the directory containing the new release. Recall your virtual host configuration. Given releases 12 and 13 your URLs might be:

   diglib12.somewhere.edu/cgi/t/text/text-idx
   and
   diglib13.somewhere.edu/cgi/t/text/text-idx

   4. Set the DLXSDATAROOT environment variable as described below for each virtual host

CAVEAT: The session ID is stored in a cookie. Search History and Bookbag are stored in the session so crossing between different releases will drop the Search History and Bookbag holdings because the session ID is a handle to a record in the database and different releases have different databses. Similarly, portfolios are stored in the database. A portfolio created in one release will not be accessible if the user crosses to a different release.

Pointing two different DLXS releases at the same data

Data (SGML/XML, image files) and XPAT indexes occupy a lot of disk space. DLXS middleware recognizes the DLXSDATAROOT environment variable. A given release can point to the data/index/image directories (under obj, idx and img) outside of its own install tree.

If the virtual host for a given DLXS release defines DLXSDATAROOT, that value is used as the path prefix for the obj, idx and img directories. If DLXSDATAROOT is not defined, the DLXSROOT value is used for the path prefix.

For example, in the virtual host for release 13, you could set DLXSDATAROOT to /usr/local/dlxs12 to have release 13 read data from the release 12 install tree.

Another scenario might be to have your data in a single location entirely outside any install trees and use DLXSDATAROOT in every virtual host to point at that single location.