IBM InfoSphere Information Server 8.1 installation hiccups

Recently while installation IBM IIS, I came across some silly errors which is worth documenting. For some reason I didn't see problem with 8.0.1. I think most of the probblem arises if you have any old installation of IIS on the machine.


So, here we go
#1. The installation wizard gives a wierd no clue error message and terminates.
Suggesting to fix the issue before proceeding.

Error is something like this:
this is GUI error and you see the same using console installation

if you will look at the log also it will not make any sense.

Apr 29, 2010 2:22:05 PM , INFO: com.ascential.acs.installer.utils.uservalidation.UserValidationBuildAction execute
Apr 29, 2010 2:22:05 PM , SEVERE: com.ascential.acs.installer.utils.InstalledProductBeanWizardBeanCondition
ServiceException: (error code = 200; severity = 0; exception = [java.lang.NullPointerException])
at com.installshield.wizard.service.LocalImplementorProxy.invoke(Unknown Source)
at com.installshield.wizard.service.AbstractService.invokeImpl(Unknown Source)
at com.installshield.product.service.registry.GenericRegistryService.getSoftwareObject(Unknown Source)
at com.ascential.acs.installer.utils.ProductBeanUtil.isInstalled(ProductBeanUtil.java:106)

Solution:
Comment the +@sys_admin entry in your /etc/passwd file as below

[ibmpg:/opt/IBM] # cat /etc/passwd
root:!:0:0::/:/usr/bin/ksh
daemon:!:1:1::/etc:
bin:!:2:2::/bin:
sys:!:3:3::/usr/sys:
adm:!:4:4::/var/adm:
uucp:!:5:5::/usr/lib/uucp:
guest:!:100:100::/home/guest:
nobody:!:4294967294:4294967294::/:
lpd:!:9:4294967294::/:
lp:*:11:11::/var/spool/lp:/bin/false
invscout:*:6:12::/var/adm/invscout:/usr/bin/ksh
snapp:*:200:13:snapp login user:/usr/sbin/snapp:/usr/sbin/snappd
nuucp:*:7:5:uucp login user:/var/spool/uucppublic:/usr/sbin/uucp/uucico
ipsec:*:201:1::/etc/ipsec:/usr/bin/ksh
sshd:*:202:201::/var/empty:/usr/bin/ksh
#+@sys_admin::::::
esaadmin:*:811:0::/home/esaadmin:/usr/bin/ksh
isadmin:!:5474:5087:IBM IIS Admin:/home/isadmin:/usr/bin/ksh
wasadmin:!:5475:5088:IBM WebSphere Admin :/home/wasadmin:/usr/bin/ksh
db2as:!:209:5089::/db2home/db2as:/usr/bin/ksh
xmeta81:!:204:1:XMETA 81 Admin:/home/xmeta81:/usr/bin/ksh
x81inst1:!:206:1:XMETA81 Instance Owner:/home/x81inst1:/usr/bin/ksh
x81fenc1:!:207:1:XMETA81 Fence user:/home/x81fenc1:/usr/bin/ksh
x81das1:!:208:1:XMETA81 DAS user:/home/x81das1:/usr/bin/ksh

#2. Second error
When proceeding with installation, it won't go beyond fence user ....

Fenced user [db2fenc2] x81fenc1
Press 1 for Next, 2 for Previous, 3 to Cancel or 5 to Redisplay [1]
-------------------------------------------------------------------------------
IBM Information Server - InstallShield Wizard

Errors occurred during the installation.
- null
- null
The following warnings were generated:
- null
Press 2 for Previous, 3 to Cancel or 5 to Redisplay [2]
-------------------------------------------------------------------------------
DB2 - InstallShield Wizard

Solution:
It seems something it does not like the vpd files. After talking to IBM they suggested hiding these VPD files, and the dshome file. Here are the steps:

We need to move (rename) the following directory and file:
$ cd /usr/lib/objrepos/InstallShield/Universal/IBM/
$ mv InformationServer InformationServer801
$ cd /
$ mv .dshome .dshome.801

#3. Third error
Operating system information: AIX 5.3
ERROR: The DB2 Administration Server is already configured for this computer.

Solution:
This was simple enough compared to the first two
This error is also for the fact the there was already a DB2 installed on the server.

===== Part 1 : make sure its stopped: =====
To stop the DB2 administration server:
1. Log in as the DB2 administration server owner.
2. Stop the DB2 administration server by entering the db2admin stop command.

===== Part 2 : remove DAS =====
remove the DB2 administration server:
1. Log in as a user with root user authority.
2. Stop the DB2 administration server.
3. Remove the DB2 administration server by entering the following command:

DB2DIR/instance/dasdrop
where DB2DIR is the location you specified during the DB2 Version 9 installation.

#4. Fourth error
Finally it was Websphere error complaining about vpd files from the old installation
I don' t have the exact error for this, but when installing the Engine it cannot proceed

[ibmpg:] #
cd /usr/lib/objrepos
mv vpd.properties vpd.properties.8.0.1