Joomla, Drupal and WordPress are the world’s most popular blogging platforms. Right now I’m staring at the WordPress “Add New Post” page, because this blog is built on WordPress. WordPress is great. And incredibly slow.
Here’s One I made Earlier
This post appeared quickly in your browser ? Great. You have been served a page that was built several hours ago. Without the pre-fabricataion, you would have had a 5 or 10 second wait while WordPress created the page from scratch. Who waits 10 seconds for a page to load these days ? Nobody, that’s who. This post compares two WordPress caching plugins and finds that WP-Super-Cache is the best because of its ability to cache compressed pages. Continue reading →
I had a customer complain of this error when trying to become ‘oracle’ user on a Red Hat 4.4 server:
[user@redhat ~]$ sudo su – oracle
Your account has expired; please contact your system administrator
/bin/su: incorrect password
The cause was that the password for the oracle account had expired (nothing to do with the user’s own account). The chage command can be used to list account expiry and password ageing information: Continue reading →
Use the Unix command line and sooner or later, you will be editing text files. One of the best ways of doing that is with the vi editor. It is available as standard on almost every unix/linux system. While other editors are available (ed, emacs, vim, etc), vi is quick and convenient. It offers a good balance between usability and ubiquity.
This article offers a workaround for the annoying “Terminal too wide” problem encountered by vi users on Solaris.
Vi was originally written for screens (terminals) which were 80 characters wide. In a modern windowing environment, the terminal has been replaced by virtual terminal apps – xterm, lterm, Terminal and many others. The width of a virtual terminal depends on how much big you make the window. On a large screen it could easily be 200 characters or more. Continue reading →
Deleting any file under Unix/Linux is usually a simple matter of using the “rm” command. Some files are more stubborn. If the file name contains special characters, or begins with a dash (“-“), it can be hard to get rid of:
bash-4.2$ ls -l
-rw-rw-r--. 1 james james 0 Aug 25 14:46 -a
-rw-rw-r--. 1 james james 0 Aug 25 14:46 logfile
-rw-rw-r--. 1 james james 0 Aug 25 14:45 some'file
bash-4.2$ rm some'file
> bash: unexpected EOF while looking for matching `''
bash: syntax error: unexpected end of file
A Few Alternatives
One obvious solution is to use a GUI. Highlight the awkward file in any file manager, hit the delete key, and it’s gone. But GUIs aren’t available everywhere. You may have only shell access to a server, for example. Continue reading →
You can recover a running MySQL database with the mysqlcheck command.
After a power cut, I found these errors in /var/log/daemon.log. This was on Debian Squeeze running WordPress 3.3.1 and MySQL 5.1.61.
Mar 22 11:22:16 debian /etc/mysql/debian-start: Triggering myisam-recover for all MyISAM tables
Mar 22 11:22:17 debian mysqld: 120322 11:22:17 [ERROR] /usr/sbin/mysqld: Table './wordpress/wp_commentmeta' is marked as crashed and should be repaired Continue reading →
This article discusses some of the workings of open source software with particular reference to the Linux kernel and GNU. It will explain some of the processes involved for those of us who know Linux but are not software engineers. Perhaps you are an Linux administrator or enthusiast, but find yourself unsure of terms such as upstream, downstream, mainline, patch, merge and other words developers love to bandy ? Read on.
Open Source Software
If you are a Linux user, you might be familiar with installing software using yum or apt-get. For example Continue reading →
The Sheevaplug is is a very small computer made by Globalscale. It is designed to offer standard computing functions in a very small space. Consuming just a few watts of power, the Sheevaplug makes a good home server, with applications ranging from network storage to web hosting and home security.
This article explains how to upgrade a Sheevaplug to Debian 6 using a pre-built image available from New IT. It is a quick and simple procedure, requiring less technical knowledge than, for example, installing Debian from scratch. Continue reading →
Copying data is something every administrator does. A single file or directory file can be copied with a single command. Moving information from one system to another needs a bit more work, but it needn’t be a pain.
The ssh command can be used to copy data from one Unix system to another. Here is an example for HP-UX, but it works on Linux too. A directory, called /var/opt/ignite, is copied from the system “pluto” to another machine called “jupiter”. Continue reading →