The Geographic Logical Volume Manager (GLVM) is a new AIX 5L™ software-based technology for real time geographic data mirroring over standard TCP/IP networks. GLVM can help protect your business from a disaster by mirroring your mission-critical data to a remote disaster recovery site. If a disaster, such as a fire or flood, were to destroy the data at your production site, you would already have an up-to-date copy of the data at your disaster recovery site.
GLVM builds upon the AIX 5L Logical Volume Manager (LVM) to allow you to create a mirror copy of data at a geographically distant location. Because of its tight integration with LVM, users who are already familiar with LVM should find GLVM very easy to learn. You configure geographically distant disks as remote physical volumes and then combine those remote physical volumes with local physical volumes to form geographically mirrored volume groups. These are managed by LVM very much like ordinary volume groups.
GLVM was originally made available as part of the XD (Extended Distance) feature of HACMP™ for AIX 5L Version 5.2. The HACMP documentation refers to this technology as HACMP/XD for GLVM. The AIX 5L GLVM technology provides the same geographic data mirroring functionality as HACMP/XD for GLVM, only without the automated monitoring and recovery which is provided by HACMP. This technology is intended for users who need real time geographic data mirroring but do not require HACMP to automatically detect a disaster and move mission-critical applications to the disaster recovery site.
Formal user documentation for GLVM is provided with the HACMP product. The HACMP/XD for Geographic LVM: Planning and Administration Guide is available online at the following HACMP documentation page: http://pic.dhe.ibm.com/infocenter/aix/v7r1/topic/com.ibm.aix.hacmp.geolvm/ha_glvm_over.htm
This book provides complete planning, installation, configuration and usage information for GLVM in an HACMP/XD environment. Using standalone GLVM in AIX 5L, apart from HACMP, is not covered in the above book. While many of the planning, configuration and usage steps are the same as for GLVM with HACMP/XD, there are a number of standalone procedures that are not covered in this book. This white paper provides some additional information you may find useful to manage a standalone GLVM configuration without HACMP.