A long line of applying database FixPaks has ended with
number 11, the last FixPak V7, and a brand new line has begun with
DB2 V8. Currently, a total of six FixPaks have been released for DB2 V8. Consequently,
support for DB2 V7 has come to an end. This event triggered many DBAs to begin the
process of database migration to DB2 V8.
IBM promotional brochures stressed V8 superiority, with its
brand new self-managing
and resource tuning (SMART)
database technology. Much was promised, including easy configuration, tuning
and management with database-enhanced automation. However, before we can check it
out, we have to upgrade our existing V7 databases.
This article is the first in a series demonstrating the migration
procedure on the SUN Solaris operating system and a single node DB2 V7
database.
In the second article, I will provide practical solutions
for important migration issues.
This article covers:
-
The Reasons
for Migration -
Preparation
for Migration -
Performing DB2
Configuration Backup and Data Backup -
Migration from
DB2 V7 to DB2 V8 - Conclusion
The Reasons for Migration
There are several
reasons why we should migrate to DB2 version 8. These are:
a.) IBM’s latest dessupport
announcement
IBM withdraws support effective September 30, 2004, for the following products:
Program
DB2(R) Content Management Product number
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
DB2 Universal Database(R) (UDB) V7.2 products
DB2 UDB Personal Edition 5648-D45
DB2 UDB Workgroup Edition 5648-D46
DB2 UDB Workgroup Unlimited Edition 5648-D46
DB2 UDB Enterprise Edition 5648-D48
DB2 UDB Enterprise — Extended Edition 5648-D50
Listing 1: IBM withdraw support announcement
b.) The concern that
arises from previously announced APARs (Authorized Program Analysis Report, a named issue with an IBM
program, opened after the customer or IBM support personnel discover a problem
with the database software code) or HIPER APARs ( HIgh Impact PERvasive APARs, critical
DB2 bugs of which all customers should be aware.) such as:
- March 15, 2002 APAR
IY30334: DB2 V7.2 FixPak 6 crash recovery problem - March 25, 2002 HIPER
APAR IY31175: Cursored UPDATE or DELETE may corrupt DB2 Version 7 data - December 27, 2002 HIPER
APAR JR17690: Fix for V7.2 FixPak 8 After displaying one entry in an
application snapshot, the CLP aborts or hangs - March 12, 2004 HIPER
APAR IY51253: DB2 instance crashed with signal 11 in function
SQLEDDB2RAASSP - April 19, 2004 HIPER
APAR IY51710: DB2 Universal Database (UDB) Version 7 hangs when monitor
switches are set.
c.) Some of the brand
new database enhancements:
-
backup
compression technique -
restoring
backup to system with different code page -
table
null and default values compression -
online
flush of database package cache -
asymmetric
index splitting with Index Type 2 -
uncommitted
data evaluation via lock deferral -
range-clustered
table support (RCT) -
online
import mode - index renaming
-
point-in-time
recovery supports a local time -
online
database check utility (INSPECT) -
identity and
sequences support in partitioned database environment
d.)
The existence
of DB2 V8 Clients
IBM has provided client backward-compatibility with numerous
restrictions. An official documentation describes this situation in the
following way: "Due to significant communication protocol changes, you
should be aware of some restrictions and limitations when accessing DB2 V7 servers
from DB2 V8 clients."
These restrictions will not prevent the version 8 client from
accessing the version 8 DB2 database, but will prevent usage of LOB, UDT and DATALINK data types,
usage of authentification type SERVER_ENCRYPT, disable password changing,
disable ATTACH command, two-phase commit, the SQL statements greater than 32 KB
in size, .
Preparing for the Migration
My demo
DB2 V7 database instance, used in this article, was running on the SUN Solaris
8 operating system, under instance owner db2inst1, hosting only one DB2
database "ARTIST" and having only one database partition.
Before
migration, some minimum technical prerequisites must be satisfied.
a.)
System
tablespace should have enough free space for double extension. This is very
important, because running out of free space could interrupt the migration
procedure and leave the database in an unusable state.
b.)
System
temporary tablespace should have enough space for future expansion. A
temporary tablespace was used during migration as intermediate storage for
catalog tables, and a sort space for the index transformation.
c.)
The number of
the log files and the log space should cover full change on the largest
database object. According IBM, migration is fully recoverable, causing full
transaction logging through the log buffer mechanism and the database log
files. That is the reason why the database log configuration parameters should
be extended. IBM recommends doubling the size for regular production
parameters. After migration, database parameters have to be reset to those
values used before migration.
d.)
Additional disk
space requirements:
- approx. 635 MB for DB2 V8 binary installation under
/opt/IBM/db2/V8 directory - approx. 2GB for a temporary logging area under under
/tmp/install directory. A DB2 installation is delivered in compressed format on
the product CD-ROM. To install DB2, you need to copy the installation image to
the temporary directory, uncompress it and perform the installation. - approx. 130MB for holding temporary trace files under
/tmp directory
