Major service changes/August 2006 web server migration
From OCF Help
The OCF has migrated to a new web server setup as of Sunday, August 6. Static content and most web applications should work correctly with no changes.
If you have any questions or concerns, please email us at staff@ocf.berkeley.edu.
The following provides a more detailed description of the changes being made and how they might affect users.
Contents |
Abstract
The OCF is migrating to a new web server setup on a new machine. This change should bring much-improved server response times and better security. The new server machine is a Sun Fire v40z given to us by Sun Microsystems; we thank them for their generous donation.
The new web server setup is running upgraded versions of many commonly-used software packages. While we have done extensive testing to ensure compatibility, there is a possibility that the upgrade will break some web applications.
While we believe most web applications will be unaffected, users whose applications fall under one of the following categories may want to review the relevant sections below.
- PHP users: see the notes on PHP if you have you have your own php.ini file.
- Perl users: see the notes on Perl, especially if you haven't made any changes in a few years or are using an older version of Perl.
- Python users: see the notes on Python if you are using an old version of Python.
- MySQL users: see the note on databases.
- Compiled applications: see the note on Compiled applications. You will need to recompile.
- Movable Type users using the Blacklist plugin: see the note on Endian issues.
Setup details
The new machine is a Sun Fire v40z with four AMD Opteron 870 processors (eight cores) and 16 GB of RAM. We run on this machine:
- Solaris 10 1/06
- Brings major improvements over Solaris 8, used on our old web server.
- Apache httpd 2.0.59
- This is a minor security and stability update over our old 2.0.50.
- PHP 4.4.2
- See the note on PHP for a discussion of changes.
- Perl 5.8.8
- See the note on Perl for a discussion of changes.
- Python 2.4.3
- See the note on Python for a discussion of changes.
- MySQL 4.1.18
- PostgreSQL 8.1.4
- MySQL and PostgreSQL are installed in a different manner for the new setup; see the note on databases for details.
Application-specific notes
PHP
The default version of PHP on the web server (/opt/local/bin/php) is now 4.4.2; this is a minor upgrade over the previous default version 4.3.10, which brings important security fixes. We believe that all extensions that were available in the old setup are available in the new one; if you need an extension installed, please contact us (staff@ocf.berkeley.edu).
We now use dynamically-loaded PHP extensions (instead of having all of the available extensions compiled directly into the binary). This makes installing new extensions and disabling unneeded ones easier. However, if you have your own php.ini file, and depend on a PHP extension that's not compiled into the new binary, you will need to make sure that extension is loaded in your php.ini file. For example, if you use the MySQL extension, you will need
extension=mysql.so
in your php.ini file. Note that most available extensions are loaded in the default php.ini file, so you only need to do this if you have your own php.ini file. If you don't know what php.ini is, you don't need to do anything; your application will most likely work without changes.
Because we use dynamic PHP extensions now, /opt/local/bin/php-full is no longer needed; while a symlink has been made for it (to our regular PHP binary), you should modify your scripts to use the default PHP interpreter.
Perl
The default version of Perl on the web server (/opt/local/bin/perl) is now 5.8.8; this is a minor upgrade over the previous default version 5.8.6. All modules that were available in the old setup are available in the new one, so far as we know; please contact us (staff@ocf.berkeley.edu) if you need a Perl module installed.
Older versions of Perl are no longer supported. /usr/bin/perl is now Perl 5.8.4 due to the Solaris 10 upgrade (as opposed to the 5.005_03 on Solaris 8 boxes). Perl 5.004, 5.005, and 5.6 are no longer available. (/opt/local/bin/perl5.005 is a symlink to Perl 5.8.8 to help ease transition, and does NOT provide full compatibility with the older version of Perl.) See the Perl release notes and the notes for your web application to see if there are any changes that need to be made.
Also, there are differences in the way Sun builds /usr/bin/perl that make it in some cases incompatible with data saved from the old server. For example, a change to use 64-bit integer types instead of 32-bit renders data stored via the Storable.pm module incompatible. There are workarounds for various software packages at various places on the internet. Also, refer to the section below on Endian Issues.
Python
The default version of Python on the web server (/opt/local/bin/python) is now 2.4.3; this is a minor upgrade over the previous default version 2.4.1. All modules that were available in the old setup are available in the new one, so far as we know; please contact us (staff@ocf.berkeley.edu) if you need a Python module installed.
Python 2.3.5 is available as /opt/local/bin/python2.3; this is a minor upgrade over the previous default version 2.3.4. All modules that were available in the old setup are available in the new one, so far as we know; please contact us (staff@ocf.berkeley.edu) if you need a Python module installed for Python 2.3.
Older version of Python (1.5, 2.1, 2.2) are no longer supported. /opt/local/bin/python2.2 is a symlink to Python 2.3.5 to help ease the transition, but does NOT provide full compatibility with the older release. See the Python documentation and the notes for your web application to see if there are any changes that need to be made.
Databases (MySQL and PostgreSQL)
MySQL and PostgreSQL no longer run in the same virtual container as the web server and web applications. This means that web applications configured to use localhost or death.ocf.berkeley.edu as the database server will no longer work. While this has not been the supported configuration for awhile, many web applications use localhost as a default setting. You will need to make sure that your application is using the supported names mysql.ocf.berkeley.edu or postgresql.ocf.berkeley.edu (depending of course on which DB your application uses) to ensure that it works after the migration.
Compiled applications
The new machine has x86 CPUs, as opposed to the old server's SPARC processors; as a result, binaries compiled on one will not run on the other (scripts are unaffected). If you need to compile Solaris x86 binaries, you may log in to asteroid.ocf.berkeley.edu using SSH (you will find GNU compilers and development tools under /usr/sfw, and Sun Studio 11 tools under /opt/SUNWspro).
Endian issues
The new machine has x86 CPUs, as opposed to the old server's SPARC processors. Due to differences in the way these two processor architectures handle data (SPARC stores data with the most significant byte first -- "big-endian" format, while x86 stores data least significant byte first -- "little-endian" format), applications that store binary data naively may function incorrectly.
In particular, this affects users of the Movable Type Blacklist plugin, which stores its data in host byte order. If you're affected by this, see [1] for instructions on how to correct the problem.
If you are developing your own application, and are storing binary data, it is safest to store your data in network byte order (big-endian format). Most programming languages have some method of converting binary data to network byte order; consult the documentation for your programming language to determine how to do this. If you are fixing an existing application, note that storing and retrieving your data in network byte order will allow you to read your old data (created on the SPARC processor in big-endian format) without problems.
