You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 6 Next »

Overview

The OpenOffice.org Community forums are hosted under the domain http://user.services.openoffice.org/ and comprise 9 National Language (NL) forums: Chinese, Dutch, English, French, Hungarian, Italian, Japanese, Spanish and Vietnamese. A total of 15 language packs are supported across the 9 NL forums, (the 9 main language plus 6 other major language variants). Across all forums there are some 75,000 registered members, who have created 300,000 posts on 78,000 topics. A typical usage is ~200,000 page requests/day, with another ~800,000 images and other resources needed to load these pages.

The forums are currently implemented in phpBB at version 3.0.8 running on Solaris Coolstack on a 4 core Solaris zone in the Oracle Hamburg machine room (at an average 3-8% us+sy load). phpBB works on a standard LAMP stack, and the test and development systems, which shadows the production system, are currently implemented on an Ubuntu 10.04 LTS VM running a standard Ubuntu server minimal LAMP configuration. The phpBB application uses both a file system and D/B (currently MySQL) to maintain application data. These are currently some 2.5GiB and 1.5GiB in raw size.

The forum software has a number of special-to-OOo modifications, and the process for carrying these forward over phpBB upgrade has now been refined over 5 phpBB version upgrades. The configuration also includes a number of custom scripts which will require some rework for an Apache.org environment and to comply with Apache SysOps and Security Standards.

However, since cloning of this system across domains is routinely carried out as part of current support processes, any relocation to Apache Infrastructure is viewed as a low technical risk activity.

Detailed System Configuration Notes

  • The configuration is largely build on a phpBB build. This is currently at version 3.0.8. This one behind current, but upgrade to 3.0.9 was deferred in view of the pending relocation to Apache Infrastructure, and will be integrating into migration.
  • Due to architectural limitations in phpBB, the 9 forums are implemented as 9 separate logical systems each with its own directory hierarchy for code and application data and its own schema within MySQL. However, since the 3.0.4 upgrade, all NL-specific mods have been merged into a single common code base, with each forum symlinked back to a version specific directory within /var/lib/phpBB. This is mainly for manageability, but this also has a performance dividend as the APC opcode cache resolves all 9 copies of each php module back to its real file-name and thus shares the same cache space.
  • Within /var/lib/phpBB two directories are maintained for each phpBB version: refXYY and comXYY, where XYY is the phpBB version number. refXXY contains the unpacked "out-of-box" kits as downloaded from the phpBB website, and comXYY the site-specific version which is symlinked into the live hierarchy. The site-specific version is generated by a patch file on the refXYY version. This file is the key customisation configuration item (CI) (currently ~990 lines) which must be regressed across each phpBB version upgrade. For each phpBB version upgrade, this patch file is regressed / refined / retested on a dev VM, then a new pair of directory hierarchies is installed on prod prior to cut-over.
  • The Apache and MySQL configurations are tuned to this application and transaction rate, but this tuning is pretty standard. Nothing esoteric.
  • The configuration also a management account use to implement a number of batch script to support routine D/B and file-system housekeeping / monitoring and to implement a mailbox to request forum posting system. The goal in doing this was to ensure that the application and system could run "zero-admin" between upgrades.
  • No end-user access to the system is required as all user, (forum) administration and moderator functions are implement though phpBBs own web interface. Most of the system administration is automated, but the system administrator does require occasional secure interactive access and sudo access to privileged operations. The watchdog scripts also require limited access. (E.g. They do a loop-back to check that the application is up and running and will bounce the AMP as an immediate action if a system stall is detected. This has been an intermittent problem with phpBB and the coolstack in the past).
  • A hot-copy backup of the DB is currently taken nightly to allow the Datacentre backup system to backup a consistent dataset. A typical daily/weekly/monthly copy of these backup sets and Apache logs are also maintained online within the file-system. A weekly offsite delta/compressed copy of the backup is also taken for D/R purposes.

Task Breakdown

Technical Issues

External Requirements

  • No labels