Monday, December 22, 2008

EBS: No OCFS2 with Shared Application Tier File System

Currently I am involved – sideways – in an Oracle E-Business Suite Release 12 implementation at one of our customers.
One of my colleagues is implementing a RAC solution with two nodes and two application servers. The platform is Oracle Enterprise Linux 4.
Before I joined, the team decided to choose OCFS2 as cluster file system for the database. A logical step would be to use OCFS2 for sharing the Application Tier File System as well.
However, we recently found out that this ORACLE product still is not supported/certified for use with the Application Tier of Oracle E-Business Suite. There are issues with OCFS2 in combination with a Shared Application Tier File System (see my article at the AMIS Technology Weblog). Somehow Oracle doesn’t seem to be putting too much efforts into certifying OCFS2 against the EBS Application Server Tier. Initially, the reason was that Oracle had to put too much work into Release 12 and Fusion. However, we are more than 2 years from the initial announcement by Steven Chan, and still no certification, even though customers are requesting it. The only workaround for the issue with OCFS2 in setting up a Shared Application Tier File System is the one proposed in my article, and it is this workaround being referred to by Oracle Support as well. But keep in mind that this doesn't mean it is supported, because it is not!
OCFS2 is a Cluster File System that is certified against and supported with Oracle Server. Why not with Application Server (EBS)? In my opinion there are many customers willing to use OCFS2, because it is stable, from Oracle and not at the least: free of charge.
By the way, the issue I found with OCFS2 also applied (at the time) to GPFS (IBM's Cluster File System). When I tried to reproduce it on AIX on Power, the issue did not reproduce. It might therefore be something related to Linux (whether it be OEL or RHEL) and not at all to OCFS2.
One thing is sure: I would want to use OCFS2 at my customers. I have enough of them who would be willing to use it.
Until that time, my recommendation is to stay away from OCFS2 with the EBS (shared) Application Tier. Use NFS, or any alternative which is supported instead.


  1. Hey Arnoud,
    For an upcoming project, I have OEL4 (is OEL5 certified and recommended?) doing EBS 12.0.6 or 12.1 w/RAC on, should I should use OCFS2 for my dbTier to keep the following:
    ASM diskgroups
    CRS voting/OCR
    ... but still keep the CRS Oracle Home, ASM Oracle Home, and DB Oracle Home all separate on local storage?
    After reading your 11gR2 new features for grid, do you have an 11gR1 Grid Features? I'd love to use 11gR2 to have a single Oracle Grid Infrastructure Home, but 11gR2 doesn't appear to be certified for EBS just yet.
    Any 11gR1 RAC/Grid papers or project outlines would be great at this phase since I hope to be starting this soon.
    Your doing a great job, as always!! Talk to you soon!

  2. Hi Kurt,
    I would definetely go for R12.1 on OEL5.3 (I believe that is the latest version and it is certified against 12.1. I have it running here and I have good feelings about it. Also, running database (refer to the new techstack features blogpost on my blog). I am not sure whether I am getting you here, but I would NEVER use OCFS2 to keep ASM Diskgroups. Is that really what you want? Please move away from that and use ASMlib for ASM. General recommendation: Don't use a filesystem to store ASM disks.
    I don't have an 11gr1 features, but I can make one for you, if you like.
    We'll be in touch!