Tuesday, 22 October 2013

wget: command not found and repolist : 0

I'm setting up a new environment to demo and workshop Weblogic and Fusion Middleware to other members in my team. After installing Oracle Linux 5.4 x86 and trying to minimize the number of packages while still using the GNOME desktop I came across a bit of a catch 22 situation.

When trying to configure the yum repository for Oracle running

$ wget http://public-yum.oracle.com/public-yum-el5.repo
wget: command not found

Now when I try to install the wget command via yum there is nothing to update and rpm shows it's not installed.

Check if there is a yum repository.

$ yum repolist
repolist: 0

I couldn't find wget in the install media after a quick look through the 5 cd iso's so was stuck and needed a repository so created my own.

Since the public-yum-el5.repo is just a series of links which are enabled or not I grabbed one

$ cat public-yum-el5_temp.repo

name=Oracle Linux $releasever Latest ($basearch)

Its important to have gpgcheck=0 or the package will fail a public key check.

Now  I can use yum to install wget and get the latest repository.

Wednesday, 3 July 2013

ORA-12162 "TNS:net service name is incorrectly specified",

Hadn't seen this for a while and good reason.

After installing 12c locally and then closing down my system, I logged in tonight to play around.

What I had forgotten to do in my haste was set the ORACLE_SID, school boy error.

ORA-12162  "TNS:net service name is incorrectly specified"

export ORACLE_SID=orcl

A simple fix from a misleading error message which might have you looking at your tnsnames.ora

Configure 12c EM Express

If like me you somehow managed to install 12c and DBCA didn't give feedback on EM Express or you didn't save the details then fear not, you can retrieve the port and change it.

If its configured you can connect get the portnumber by running:

SQL > select dbms_xdb_config.gethttpsport() from dual;
Then connect : https://database-hostname:portnumber/em/

If the SQL returns no values then you need to set the port,


Then connect : https://database-hostname:portnumber/em/

(you will need flash player as well to use it, guess that means no ipad app !)

Sunday, 30 June 2013

Setting Xhost for the Oracle User and Creating a custom Yum Repository for the local Media

In setting up environments and running the GUI I've always just used xhost + as the root user.

I'm currently moving a customer to Oracle Linux from Windows and helped out our system administrator who was on site with a list of packages needed for an Oracle Database and Ebusiness Suite ( oracle-validated took care of most things).

Its actually a great project to be involved with as we are using VMware and have created template images to deploy new environments as needed. It takes about 20mins to create a new machine which is already configured and has the Oracle Database 11gR2 software installed.

Of course in any deployment there have been missing packages not listed in Oracles Documentation(but they are on oracle support as notes for some reason)  and interactions with the GUI's when running the installers.

At the start I was using xhost + to help with the GUI's , but having come from a support background, I realized I was breaking a big rule. I promised myself that once involved with projects i'd stay away from root as much as possible( a bad experience where a person installed the oracle RAC clusterware as root).

So I needed to work out how to stop using xhost +

Answer :
The below turns back on the access control lists
$ xhost -
The below add the oracle user to the list and the local IP
$ xhost +SI:localuser:oracle
$ xhost + hostname

The second thing bugging me was that the templates were on dhcp and could use yum for installing the packages but with the cloned vm's , no such luck as they were static and locked down. I found a great note on mounting the media dvd and creating a custom yum repository which could then be used.

The steps are below :

# mkdir /media/disk

Insert EL5.7 DVD (or attach to your Oracle VM guest)

# mount /dev/cdrom /media/disk

Edit /etc/yum.conf, adding the following section:

[EL5.7 DVD]

name = Enterprise Linux 5.7 DVD




# yum install oracle-validated

The last step was to go back to the template and update it with all the lessons learned from the first couple of environments.

Friday, 28 June 2013

Scaphoid Fracture and Oracle 12c

After taking up American football with the American Trojans back in October I had an injury on St Patricks day which I put down to a sprain. 8 weeks later and after some physio I decided to get an Xray and found out I had a fracture.

I've had a cast on the arm for the last 6 weeks so although i'm working and in the middle of an R12 upgrade for a customer and studying for the 10g OCM , 11g OCP upgrade exams, blogging has been put on a back burner.

I think I'll need to start back with Web Services , ODI when I return as their is enough blog posts about the release of 12c which would put me to shame. I installed it on the 2 hour return train journey the other day without any issue on OEL 6_4 and look forward to playing with it. The guys over at pythian already have a great post on setting up a 12c RAC cluster on the laptop, building on previous post on setting up the 11gR2 cluster.

Having read the 12c concepts guide, they have a nice picture of a bunch of DBA's being replaced by Container and Pluggable database Administrators. I'd just about convinced my friends what I did, now I have to learn a whole new piece.

Tuesday, 14 May 2013

VirtualBox hde: irq timeout: status=0x50 { DriveReady SeekComplete }

If you get the below error when trying to install Linux ( in my case Oracle Linux) through virtualbox on a windows machine then then the reason will probably be that the hard drive created for the virtual machine has been created as a SATA drive by default.

ide: failed opcode was: 0xef
hde:hde: irq timeout: status=0x50 { DriveReady SeekComplete }

Remove the image from SATA controller and add it under IDE controller to resolve the issue

Great tip from the folks at the virtualbox forum
**EDIT 19/05/2013**
Setting up your VM's under IDE is fine but limiting to 4 disks. In trying to create a 10g Cluster using multiple ASM disks i realised i was going to find another way around this problem.
To convert from IDE to SATA, boot the existing VM with the IDE disk, then force-add the SATA driver to a new boot image for the running kernel version as root

mkinitrd -v -f --with=ahci /boot/initrd-`uname -r`.img `uname -r`
Now before shutting down the machine, you will want to update your /boot/grub/grub.conf with the below to avoid the same errors as the start of this post.
Add this line at the end of the kernal argument
before : "kernal /vmlinuz-2.6.9-78.EL ro root=/"
after : "kernal /vmlinuz-2.6.9-78.EL ro root=/ ide2=noprobe ide3=noprobe"

Getting Started with Oracle Data Integrator

Just before i finished for 2 weeks leave ( new arrival to the family last week) I had the opportunity to spend some time working with Oracle Data Integrator , ODI.

The challenge set was to help automate the loading of external XML files using ODI to start and then use its other functionalities in the future like exposing some of these processes as web services.

I had spent some time using the Oracle 'Getting Started' document : http://docs.oracle.com/cd/E28280_01/integrate.1111/e12641/toc.htm

I also purchased this book 'Getting Started with Oracle Data Integrator 11g: A Hands-On Tutorial' which was an excellent introduction into using ODI and even had a couple of sections on using XML.

Although my main responsiblity was to tackle the architecture and deployment of all the components, I'd spent some time playing and so was able to get involved with the early design solutions.

The next posts are going to cover deploying the components and then a few posts on using it to load data in from an XML file , from a database source to target, enriching the data ....