Mark Allen

Linux

Disk Performance

Using hdparm to measure a hard disks performance. To measure the current performance of your disk run: hdparm -tT /dev/sda You will get something like: /dev/sda: Timing cached reads:   896 MB in  2.01 seconds = 446.06 MB/sec Timing buffered disk reads:  168 MB in  3.01

Oracle

ORA-20603: Updating timezone region of a target is not supported

Enterprise manager does not start after updating the database. The emdb.nohup has an ORA-20603: Updating timezone region of a target is not supported error message in it. The problemThe timezones have been updated within the database. SolutionAs Oracle run: $ORACLE_HOME/bin/emctl resetTZ agent and follow the instructions.

Oracle

Oracle XE Client Connection String

Oracle XE Client does not come with sqlnet therefore you need to connect to the database using a connection string. Oracle XE Connection String username/password@[//]host[:port][/service_name] * port is required if the port number is not 1521. * service_name defaults to XE.

Oracle

Viewing Oracle Application Server JMS Queues

When developing BPEL and ESB applications it is necessary to see if the message you sent actually made it on the queue. Using Hermes is an excellent way to view an application server queues and topics. ProblemNeed to view messages on a JMS Queue or Topic that you have published

Oracle

Changing JMS Connection Password in Oracle SOA Suite

By default the the password for eis/Jms/TopicConnectionFactory JMS Connection is welcome1. This needs to be changed if the oc4jadmin password is not set to this. ProblemAfter creating an ESB process you are unable to write to a JMS topic.  The following error message is displayed in the ESB

Linux

Updating VMware Server Serial Number

How to update a linux VMware servers serial number from a windows VMware console. Get the serial number from http://www.vmware.com Open up the VMware Server Console on the windows machine and login to the linux server as root. Click on Help -> Enter Serial Number Enter

Cygwin

Installing Cygwin for Windows XP

Instructions on how to install Cygwin on Windows XP, setup ssh and create a shortcut for rxvt. Pre-InstallDownload setup.exe from http://www.cygwin.com/ InstallRun setup.exe The basic tools required are: * openssh * rxvtOther packages will also be installed in order to support these. Click Here to view a

Linux

Setting up VMware Server on Linux

Instructions on how to setup VMware server on linux and access it from a windows machine. Pre-SetupDownload VMware server rpm for Linux from http://www.vmware.com and register for a free serial number.  The current version is 1.0.3. Setup access to the server. See Installing Cygwin for

Oracle

ORA-01033: ORACLE initialization or shutdown in progress

The Oracle database is in the process of initializing or shutting down. Typically this occurs when the database service is in the process of starting or stopping. ResolutionWait for the database service to start.  If it does not start check the database alert.log to see what the underlying issue

Oracle

ORA-12505, TNS:listener does not currently know of SID given in connect descriptor

The database trying to be connected to is not running. Ensure the Oracle database is running and that the TNS entry you are using is correct. Resolution Start the Oracle Database Windows start the OracleServiceXE service. Linux login as oracle and run dbstart. Test TNSTo test TNS run tnsping on

Oracle

Oracle XE Tuning

Oracle XE is an excellent starter database, but under typical loads, the out-of-the-box parameters need to be increased. Database Sessions Increase the number of sessions that the database can handle simultaneously. This will allow for more users to access the database. sqlplus /nolog SQL> show parameters sessions SQL>

Oracle

Starting Oracle Enterprise Manager

For the oracle database Enterprise Manager (EM) runs on port 1158. But it needs to be started by itself. LinuxLogin as oracle and run: $ORACLE_HOME/bin/emctl start dbconsole On some systems a xserver session needs to be running for the graphs to be created correctly.  The best solution

Oracle

Oracle XE Backup

After installing Oracle XE you should setup backups. Backups for XEFor Oracle XE there is ready a backup script that uses Oracle's RMAN. Setup Archive Log ModeAfter installing the database change it to archivelog mode: [oracle@localhost ~]$ sqlplus /nolog SQL*Plus: Release 10.2.0.1.0 -

Oracle

Checking for a User in OID

Test to see if a user is already in OID The following java code checks to see if there is a user in OID, returning true if they are there. import oracle.ldap.util.*; import oracle.ldap.util.jndi.; import java.io.; import java.util.; import javax.naming.; import javax.

Linux

Creating a new linux file system

Creating a ext3 file system on a new USB disk. Partition Table# /sbin/fdisk /dev/sdc The number of cylinders for this disk is set to 60801. There is nothing wrong with that, but this is larger than 1024, and could in certain setups cause problems with: 1. software that

Linux

Copying directories between file systems

Copying files from one directory to another using find and cpio. cd /old_file_system/ find . -print -depth | cpio -pamVd /new_file_system/

Perl

Getting https pages with Perl

Perl's LWP package is a great way to get web pages and display the content of the resulting http header. Out of the box it does not support https, the following describes how to configure perl to access https pages. Configure CPANThe first thing to do is to

Apache

Using Java Web Start with Opera

Out of the box the Opera web browser is not setup to run jnlp files, therefore java webstart will not run properly.  To fix this a new mime-type needs to be added to the browser.  Follow instructions at: http://www.opera.com/support/search/supsearch.dml?index=470

Apache

Adding LDAP Authentication to a Site

Add the following entry to the VirtualHost <Directory "/var/www/html"> order allow,deny allow from all AuthName "Staff only" AuthType Basic AuthLDAPURL ldap://localhost/dc=example,dc=com require valid-user </Directory>

Linux

Link down on RedHat Linux 3

On RedHat Enterprise 3 Linux on VMWare each interface link is always down. The following needs to be added to all the ifcfg-eth in /etc/sysconfig/networking-scripts/ check_link_down() { return 1; } See http://www.vmware.com/support/guestnotes/doc/guestos_redhat90.html for more information.

Linux

No output from the Console when connecting to a Server running on Linux

The problem is that the vmx file is not executable.  Go to the VM directory and run: chmod 755 *.vmx Then restart the vmware server, output will then be displayed on the console.

Linux

Syslogd Stops working after installing VMWare Server

Seems that VMWare server adds a new service to the /etc/service file.  If you have SELinux running the file's security context changes. To fix run: /sbin/restorecon /etc/services For more information see http://www.vmware.com/community/thread.jspa?messageID=435464

Linux

Mounting ISO in Linux

To mount an ISO file in linux so it turns up as a directory structure do the following: mount -o loop -t iso9660 filename.iso /mnt/iso Simple as that.

Linux

Installing Java on Fedora Core 3 using JDK 1.4.2

Excellent Howto for setting up Tomcat5 from jpackage.org on RedHat Fedora Core3. http://www.mksearch.mkdoc.org/howto/jpackage-sun-fc3/ But required JDK 1.4.2 to be used in place of 1.5 Downloaded http://mirrors.sunsite.dk/jpackage/1.6/generic/non-free/SRPMS/java-1.4.2-sun-1.4.2.

Linux

Setting up sshd for Public Key Authentication

To create key only authentication the users public key needs to be put on the server in their home directory under .ssh/authorizated_keys. Create the users private key on their workstation: ssh-keygen -t rsa Send the private key to the server: cat .ssh/id_rsa.pub | ssh newmachine "