<IfModule mod_userdir.c>
<Directory /home/*/public_html>
php_admin_value engine Off
</Directory>
</IfModule>
and disable it, either by deleting or by commenting it out (precede each line with # sign). You can also change php_admin_value engine setting to On, but if you do that, you will be unable to turn off PHP engine in .htaccess files.
]]>apt-get update apt-get dist-upgrade cat > /etc/apt/sources.list << ENDF deb http://ftp.us.debian.org/debian/ testing main deb-src http://ftp.us.debian.org/debian/ testing main deb http://security.debian.org/ testing/updates main contrib deb-src http://security.debian.org/ testing/updates main contrib ENDF apt-get update apt-get dist-upgrade touch /etc/udev/kernel-upgrade dpkg -i /var/cache/apt/archives/udev_151-3_i386.deb apt-get dist-upgrade -f
After that upgrade should finish. But be warned – after switching from lenny to squeeze I’ve experienced some problems like kernel not booting (I run previous version and regenerated initrd – it, or something else, helped), problems with VirtualBox guest additions (had to install kernel sources for guest additions to build themselves, then reinstalled virtualbox-ose-dkms package, and then reinstalled guest additions from the CD image attached to VirtualBox).
Upgraded system needs a few touches, but that’s not unusual. Don’t worry about “udevd : SYSFS{}= will be removed in a future udev version, please use ATTR{}= to match the event device” and similar messages while booting – it will be silenced in future versions of some packages. You can fix it if you want by replacing SYSFS with ATTR in /etc/udev/rules.d/* files, but other similar warnings will appear. You can also run upgrade-from-grub-legacy script, if you chose to chainload new grub from the old one during the upgrade. There is also significant amount of files in /var/cache/apt/archives, which can be safely deleted after successful upgrade (in my case it was 2.5GB of data).
Phew, now everything works and I have a proper VirtualBox image of Debian Squeeze.
]]>From the old times as a sysadmin I’ve remembered that copying, doesn’t matter local or over the network, was faster if data was copied in chunks – that was true especially when having a lot of small files.
So, to kill two birds with one stone, I employed… tar. Yeah, it’s a very versatile tool – in some time I’ll describe how to use it as a part of a network encrypted backup solution. But here, I used only two instances of tar. You have to remember that if you specify absolute path to the directory you want to transfer, tar will record all elements of the path, only stripping “/” from the beginning. So there are two ways: either record whole path and strip it when “decompressing”, or not to include it at all.
Lets assume that we’re copying data from /media/external0 to /media/external1.
First option:
cd /media/external1 tar cf - /media/external0 | tar x -f - --strip-components=2
Second option:
cd /media/external0 tar cf - * | tar x -C /media/external1 -f -
The first tar command “compresses” the data (either from given directory or from the current one), sends it to the standard output, which goes into the second tar’s input, which decompresses it into the target directory.
To see the progress, you can put cpipe application in the middle like that:
tar cf - /media/external0 | cpipe -vt | tar x -f - --strip-components=2
One note on an improved performance using this method. I didn’t do any benchmarks, but it shouldn’t be worse than a standard cp. tar will be better if the OS is not using any smart pre-buffering. Also I’ve decided to write this entry as an introduction to a future one about over-the-net backup using tar
]]>
On Unix-like operating system I’m using host command to resolve hostnames into IP’s and the other way. On Windows, there’s a nslookup tool, which works just like the Unix equivalent, but to get accustomed to PowerShell, I’ve decided to write a function, which uses internal command to do NS lookups.
Generally, to resolve a hostname you can use this one-liner:
[System.Net.Dns]::GetHostAddresses("devplant.net")
You can shorten it by declaring a short function.
function resolve( [string] $in ){
[System.Net.Dns]::GetHostAddresses($in)
}
(Defining functions remember not to collide with pre-existing variable names)
But this is only one-way command – to resolve IP address into a hostname, you have to use other command:
[System.Net.Dns]::GetHostbyAddress("72.21.210.250")
To combine both functionalities, you can extend our function, using regular expression to do a naive recognition of IP addresses.
function resolve( [string] $in ){
if ($in -match "(\d{1,3}\.){3}(\d{1,3})") {
[System.Net.Dns]::GetHostbyAddress($in)
} else {
[System.Net.Dns]::GetHostAddresses($in)
}
}
Now here’s how you can use it:
PS C:\Users\leafnode> resolve devplant.net
IPAddressToString : 91.192.224.142
Address : 2397093979
AddressFamily : InterNetwork
ScopeId :
IsIPv6Multicast : False
IsIPv6LinkLocal : False
IsIPv6SiteLocal : False
PS C:\Users\leafnode> resolve 72.21.210.250
HostName Aliases AddressList
-------- ------- -----------
210-250.amazon.com {} {72.21.210.250}
PS C:\Users\leafnode>
]]>
You want to try Firefox 3.5 but your favourite extensions are not compatible with the new version? There is a possible solution for this problem.
As in case of extension interface nothing much changed between Firefox 3.0.* and 3.5, it is possible that extension compatible with older version will work without any changes – except the maxVersion setting, which prevents Firefox from installing apparently incompatible extension. Manually, you’d have to download XPI file, decompress, edit settings, re-compress, and install from file. Quite cumbersome, but…
Extension MR Tech Toolkit allows you to tweak some of the extensions’ settings, including maxVersion, without any hassle. Just right-click on an incompatible extension, select “Make compatible” from the menu, and that’s it! After Firefox restarts, if extension really is compatible, it will be working fine.
]]>
Windows XP on a netbook works fine with me, but as a person with Linux background it seemed natural to try some distribution on my Wind. As I wanted to try it first, I’ve decided to user some live distribution first. I don’t have an external CD device, but on a previous occasion I’ve managed to cope with bootable USB drives, so it was a natural (and only) choice. I was just about to re-format pendrive I’ve used to boot Linux from, but then I remembered that I have couple of loose 2GB microSD cards I’ve bought just because they were cheap, and an USB card reader. Idea of having an operating system on a so tiny memory card was very appealing!First, you have to download files: Ubuntu Netbook Remix disk image (about 1GB) and Image Writer for Windows. Then, plug in your desired USB flash device and run Image Writer. Choose click on “…” button, choose downloaded Ubuntu image, select drive letter of your desired device (be careful as this device is gonna be totally overwritten), and click “Write”.
And that’s it! From now on, you can boot operating system from this device as long as computer’s BIOS supports that.
As for MSI Wind, during bootup, you can press F11 to enter booting device choosing menu. Then you can select your USB device – some devices show as an empty line, but you can still choose it. In this menu you can see also mult-card-reader – and yes, this means that you can just plug SD card into your reader and boot operating system using built-in reader!
Links:
Second, you can get fixed packages from unstable branch of Debian repository. This generally works, but you would have to include all dependent packages, what could be quite large amount. All necessary packages can be found here, but I didn’t test them.
Third option, which I have chosen, is to do a temporary fix by adding line http-library=serf to your ~/.subversion/servers file, and after new packages are available, upgrade them.
I have bought my MSI Wind as soon as they were available in Poland, in July last year. It was quite some time ago, so I decided to update BIOS. I downloaded it from MSI official page, prepared bootable pendrive using HP USB Storage Disk Format Tool (downloadable from here) and Windows 98 boot files from my own archives (you can find some boot disk images at bootdisk.com). After extracting BIOS files to the pendrive, I’ve booted system from it.
First trail of running flash.bat failed with message “ERROR: BIOS has no flash information available“, and it appeared that I have to have an AC adapter connected throughout BIOS update procedure – quite obvious, but I forgot about it. First reboot, everthing went fine, Windows XP found some new device and that was it. But I’ve also updated some drivers which required system to reboot, so I did.
And system did not start after reboot – it all finished at the black screen with XP logo and animated slider. Safe mode also didn’t help – all I received was black text-mode screen with blinking cursor after loading drivers.
My first thought was that some new driver was not functioning properly, so I decided to try to repair system using Windows XP install CD. I spent two hours struggling with creating XP installation pendrive (as I don’t have external CD drive), but with a partial success – now I have XP setup pendrive, but I didn’t solve my problem: Windows installer hung with “Setup is now starting Windows” message. I thought that maybe even SP2 install needs SATA drivers, so I built another installation drive using nLite to include Wind driver pack, but result was the same.
After some googling I found hints to try to go through BIOS settings and disable unnecessary things, and that was a bullseye. I got into BIOS setup and first thing I seen was a message “I you have changed overclock settings and system is not booting, try to unplug AC adaptor, remove battery, reattach battery and AC adaptor and try again”. And that was it. System booted smoothly.
I hope that this will save some trouble if anyone encounters problem like I did.
]]>What will be changed in Drizzle in comparison to MySQL? First of all, whole architecture will be changed. Drizzle will be not monolithic chunk of software like its predecessor, but it will be based on microkernel idea. Most features will be moved from core to optional modules. Those features, like triggers, views, or even query cache, are standard for modern database servers, but are very rarely used in webapps (which is very strange for me, but I’ll come back to this later). One of these modules will be InnoDB engine (owned by Oracle, double licensed), which would make upgrading to newest version of that engine easier. UTF-8 will be standard. Generally – looks nice.
On the other hand, Windows users will be sad, because probably (but not for sure), Drizzle will be available only for Linux and MacOS X. Maybe it’s not such a big deal, because most of production servers are working under non-windows OS’, but for development it would be nice to have a possibility to test-install this RDBMS on Windows.
Some highlights from features list:
When I first got into web programming, PHP was used mainly for guest books and simple visitor counters – as an extension of good old perl CGI’s. And even for those puny applications SQL databases were used – most commonly MySQL. It annoyed me, as I thought that installing RDBMS for that sole reason was a terrible overkill. On the other hand, using files was quite cumbersome, as a programmer had to take care of file locking (and still from time to time data tended to disappear). That time, something like “raw data files with concurrency” would be great. But times have changed, and web sites are something more than a set of HTML files with CGI-like gizmos. Now everyone can use a CMS system to create web page without any knowledge of Internet voodoo. Every CMS is backed by a database server, but I haven’t seen a CMS system that uses database for something more than a data storage – no triggers, views, stored procedures – nothing. I could understand if it was because of support for many different RDMBS’, but usually even if software supports e.g. MySQL and PostgreSQL, the second one is broken/unusable/modules use MySQL non-standard methods.
And here comes Drizzle. RDBMS with basic SQL support (but it’s not any standardized SQL dialect), with optional advanced features like views (views support is ‘advanced feature’… o tempora, o mores…) For webapps – great solution, if only it’d become a standard (because of not standardized SQL syntax).
But what about “big” MySQL? I’ve never considered it as a tool for more complex projects. Websites – maybe, if software does not provide proper support for PostgreSQL. PostgreSQL is my choice for hobby projects (and those without big funding), Oracle for other.
MySQL was never percieved as a free replacement for expensive databases (except for people not knowing what they are talking about), so what would be MySQL’s “biotope” with poor opinion from large traffic applications programmers and Drizzle taking its place as a choice for webapps?
I know that my opinions on MySQL may be controversial, but they are based on my personal experience, and please don’t argue with that :)
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