Some random nerd stuff I picked up recently.

1. How to know your Linux (Red Hat) version
# more /etc/redhat-release
It'll show you something like:
Red Hat Linux release 9 (Shrike)

2. How to know your kernel version
# uname -r
It'll show you something like:
2.4.20-28.9smp

3. How to install software using an RPM file
# rpm -i some.cool.rpm-file-here.rpm
Use -v option for verbose output:
# rpm -iv some.cool.rpm-file-here.rpm
It'll tell you later whether the installation is successful or not.

4. How to install Oracle Database
Follow the documents and never -- repeat, never -- skip a step, no matter how trivial you think it is. I did, naturally, and here's what happened.

I managed to install everything successfully. Then it was time to test the Oracle Management Server by making sure the OracleOraHome92ManagementServer service -- yup, it's Windows -- was started. It was not. And when I tried to start it, it gave me this:

The OracleOraHome92ManagementServer service on Local Computer started and then stopped. Some services stop automatically if they have no work to do, for example, the Performance Logs and Alerts service.

Event Viewer told me to look at oms.nohup file. Which basically informed me of a lot of java.lang.NullPointerException errors.

After a few wasted hours -- they don't say Oracle stands for Ora Kelar-Kelar for nothing -- I finally went back through the installation steps. And sure enough, here's what I had skipped earlier.

"Other Cleanup Tasks
1. You also need to set up your environment so that the local host name can be resolved without the need to look up DNS. To do this, edit the C:\WINNT\System32\Drivers\Etc\Hosts file. Add the IP address and fully qualified host name for your computer after the localhost line currently in the file. Save your work and close the file.
2. If you have used a previous version of this OBE before, you must remove your NTOEM user from User Manager.
3. Reboot your machine."

Well, well, I had not thought it was necessary -- since I was such an expert in sysadmin *yeah, right*. Anyway, apparently Oracle is less an expert than I am, so it needs more guidance. I added the line, rebooted the machine, and voila! That friggin' OracleOraHome92ManagementServer started smoothly -- just as advertised. What do you know.

5. How to connect to an Oracle database when there might be more than one Oracle instance installed
Sometimes it's necessary -- hell, it's even insisted by Oracle -- to install more than one Oracle version on one machine, in which case different directories have to be specified. The thing is, while Oracle own applications, like SQL*Plus, can then connect to a database, others, like Toad, might have problems and you might get this "TNS: no listener" error. These external applications need to know which Oracle instance is to be used.

And so there's this 'hidden' TNS_ADMIN environment variable. Just create a new environment variable and name it TNS_ADMIN. Set its value to the admin home directory of the Oracle instance you prefer to use, where tnsnames.ora file can be found. In my case it's:
C:\oracle\ora92\network\admin

BTW, does anyone know where to get a replacement drummer on such a short notice -- less than 24 hours?

Current music: Dewa - Restoe Boemi
Current mood: happy