Web technology Category

Ripe today will start allocating IPv4 IPs from the last /8 block

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IPv4 are running out for all the regional registries and today Ripe NCC will probably start allocated IPv4 requests from the last /8 pool. This means no more PI space can be allocated and new LIRs will be assigned only 1024 IPs, not 2048 IPs as it used to be. See the daily allocated graph yourself:


Welcome to the IPv6 world my friends!… Read the rest of this entry »

Protect .svn folders on Apache or Nginx web servers


Sometimes I use subversion (svn) to publish my latest web sources to web servers and it’s always good to secure your .svn folders on the web server. You can easily do it for an Apache and nginx web servers.

I have published quick config examples below – feel free to use!

Apache config httpd.conf:

<DirectoryMatch .*\.svn/.*>
Deny From All

Nginx config nginx.conf:

location ~ /.svn/ {
deny all;

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Sorry but the board is temporarily unavailable, please try again in a few minutes. phpbb error

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If you have noticed the following error after installing new phpbb forum:

Sorry but the board is temporarily unavailable, please try again in a few minutes

You may want to login into Administrator panel and go to General Tab -Load settings and change value of Limit sessions from 1 to 0 (unlimited).… Read the rest of this entry »

Enable Firefox full URL display

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New Firefox versions effectively hide full URL and when you copy the URL it adds http:// or https:// automatically (which is annoying), but it doesn’t show up URL bar by default.

To change it, enter the following in URL location and hit Enter:


Then find the following value:


and Toggle it to False.
This is it, now Firefox will display full URL in a location (URL) bar.… Read the rest of this entry »

G-WAN super performance web server daemon


At LKJ.NET blog we usually cover new technologies that allow to scale your web site to new heights. A few weeks ago I spot a new and promising star in the universe – G-WAN web server daemon/software. From the benchmarks it claims to be the fastest web server daemon available on the planet easily beating Nginx and Lighhtpd with a large margin (3-4 times usually). It can easily saturate 10G network up link by serving static content and is ideal for Web 2.0 noSQL stores and similar technologies where phenomenal high speed and low latency is a must.

G-WAN is … Read the rest of this entry »

Increasing httperf maximum number of open descriptors from 1024 to 65535


By default httperf on Linux compiles with 1024 open descriptors and that can be a problem when you plan to test high bandwidth and many concurrent connection web servers.

For safety you can edit /etc/security/limits.conf however you will also need to change the following file before you compile httperf software:


and find the following line:

/* Number of descriptors that can fit in an `fd_set’. */
#define __FD_SETSIZE 1024

and replace it to

#define __FD_SETSIZE 65535

Now you can compile httperf.
The original string that’s displayed when you run httperf without editing typesizes.h definition file:

httperf: maximum number of

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Playing around with Linux Virtual Server (LVS)

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I haven’t disappeared folks – I’ve been playing around with Linux Virtual Server (LVS) in the last days and it’s been actually a great experience. Please expect LVS Layer 4 load balancing posts very shortly.

I am currently using Centos 5.6 version with built in IPVS module, but will be compiling custom kernel for best performance. Please hold on – I will have new posts shortly.… Read the rest of this entry »

Ping blog update service sites

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When you publish a new content on your blog, you need to notify Update service sites that your blog has new and fresh content available. At first it may sound a bit complicated process to set-up, but it’s easily done with WordPress built-in feature called “Update services”. A lot of folks refer to it as “blog ping” service.

So why do you need to notify these blog update service sites about fresh content?
To get more feed readers, web visitors and increase your blog popularity. Many folks have signed up with these Update services sites and are automatically receiving notifications … Read the rest of this entry »

Create image thumbnails to increase speed and visitor experience

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We all know that large file download takes extra time for web visitors and increases bandwidth bill for your blog or web site. It’s imperative to keep down the image size and offer large image thumbnails in-preview mode rather than calling image directly with IMG SRC tag. Let’s do some simple bandwidth and load time calculation with a large image and much smaller thumbnail image.

Web visitor count: 50.000
Thumbnail image: 64KB
Large image: 640KB
Visitor with low speed connection: 256Kbps (download speed)
Visitor with fast speed connection: 2Mbps (download speed)

If all 50,000 visitors will fetch your large image … Read the rest of this entry »

Perlbal for load balancing

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Perlbal can process hundreds of millions of hits daily on a medium hardware server. No wonder it’s used on high load sites like Vox and LiveJournal.

It offers load distribution to multiple back-end servers and different load balancing algorithms that will mostly suit all web site needs. We will be testing this proxy software and compare how does it perform comparing to nginx.

Perlbal web site URL: http://www.danga.com/perlbal/Read the rest of this entry »