> We want to convert a MMBase 1.5 environment currently running 
> on Postgress SQL 7.1/Linux Redhat 7.3 /Tomcat 4.0-4.1 to a 
> MMBase 1.6 on a Oracle/Sun Solaris 9/OC4J enviroment.
>
> We have the following questions, does anyone have the answers ?
> -How to migrate the current data from Postgress SQL to 
> Oracle, are there tools/scripts -Which version of Oracle 
> should be used (8.1.7/9.2.0) -Will OC4J be supported (Orion 
> server adapted by Oracle) -What are the hardware requirements 
> Processor/Memory with the following

Hi Laurens,

You will probably run into some issues with mmbase and oracle. The 1.5.1
release had a MMOracle class that did work with oracle 8.1.6 (Thin and OCI
driver). MMBase 1.6 had some change in the datamodel which introduced some
backward compatibility issues with the old database classes. I don't know
how much the database classes of Oracle are up-to-date. I never had to run
MMBase 1.6 on Oracle. I hope we wiil support a stable oracle version again
in 1.7.?.

Converting a database from one vendor to the other can be done in the way
how Eduard and Kees wrote. Both can be used when it is not a weekly/monthly
task or when it does not have to be reproducable. We have a migration tool
for Web-In-A-Box to migrate existing databases to a newer version of WIAB.
There are more then 30 old WIAB instances which have to be migrated to a
newer version in the future. So it is almost w weekly task for us and we
have to reproduce it many times with different input and ouput
WIAB-versions.
This tool does not require any mmbase instance and copies from one database
to the other. DataModifiers in the copy process can manipulate the data
before it is written to the output database. Some tricks we perform are
adding columns, renaming columns and splitting up columns into multiple
ones. BMP images are converted to jpeg. Some MMBase objects are deleted and
replaced by new ones. Some dataModifiers are very specific for WIAB, but it
is configurable which ones to use.
The tool is not yet ready to release it as open source, but it might be
somewhere in the future.

I can't say a lot about the numbers. IMO, they don't sound to shocking. It
depends a little on the sites what kind of server you need. Let's say you
have a good network connection with an Intel Xeon dual 3.0Ghz and 2Gb of
memory then you should be able to easily process about 30 concurrent users
on you system. And in this example I am not talking about a commercial
enterprise database and app-server. Just the usual
apache/tomcat/mysql/postgresql setup.

Nico Klasens
 
Finalist IT Group
Java Specialists


Reply via email to