Petr’s blog about Linux

I decide to create hotspot from my server to allow other connect to Internet for free. I used “Captive portal” solution based on these applications:

• CoovaChilli
• FreeRadius
• MySQL
• daloRADIUS

When somebody wants to connect to Internet using my wifi, the first page he can see is the register/login page (whatever page he wants to visit).
After registration/login he is able to connect to Internet.

So let’s see how I did it.

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I got 16 GB USB flash from my brother, because he can’t see me still using my old 64 MB. He decided to buy Imation Nano-Flash-Drive.

Because of many of my friends and colleagues are using Win, I use NTFS on it. Old FAT is not “usable” in these days, because it can’t handle bigger files.

From the first time I use USB disks I always want to have bootable disk/flash with live CDs – so here are few notes how to create USB flash drive able to boot stored live CDs:

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One day I checked dmesg from one of my servers and I saw I/O errors

Lucky for me there are two disks in RAID 1 so my data was not lost. The machine is “just” firewall, so I decided to play little bit with the bad hard disk, because there are no important data on it. Usually if you see errors like I mentioned above you replace disk without any questions, but I would like to “get” some outputs from diagnostic commands. So you can see what you can do in such case.

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I need to connect to the Oracle database in my work to get some data from it. I’m not the Oracle expert, but I decided to use DBD::Oracle.

Most of the manuals and how-to pages describe, how to install client libraries to system (usually as root), which was not my case.

I just need one directory with libraries in my $HOME and few scripts to get some data from the database – no system installations.

Here are the steps how to install DBD-Oracle and it’s libraries to “one” directory without doing mess in the system:

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I have problem with Java Webstart applications, which are using IPv6 by default. Because I’m not using IPv6 at all I decide to disable this protocol completely.

There are many pages how to disable ipv6 under Debian, but most of them was not working for me.

The most easiest work well:

Modify /etc/default/grub:

Don’t forget to run update-grub after change (and reboot).

Then if you run

you should not see any IPv6 addresses…