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This site is a collection of my own work with Linux. Certain things are easy, others take time to decipher and if I ever need to repeat the work (which usually happens!), then I need to remember everything by memory or... have a site with all the steps taken and to take again.

The following are my most recent posts:

CVS and really large files

Yesterday, I got a nice little surprise...

I inadvertendly added two copies of an uncompressed MS-Access data in my CVS. The files were over 400Mb (about 434Mb if I'm correct.) This started okay, then slowly I could see my memory going banana.

Wow! It took a good 20min. to check-in. My CVS is on my computer, so it is not the transfer that's slow... The fact is, the allocated a buffer for the entire file! My computer was on its knees!

gVIM surprise!

What a surprise!

Today, by mistake, I loaded a URL in gVIM instead of my browser. The mind going silly I guess since I had to type :e<space> to load, as usual...

And to my surprised, it loaded something. Yes! It actually sent the necessary HTTP request and shown the reply in my gVIM window!

What does this mean? Well! That means I can check out my websites directly in gVIM to see whether they worked as I expected.

Fantastic! If you ask me... 8-)

Submitted by Alexis Wilke on Wed, 12/24/2008 - 23:13

Well... I knew that a firewall could generate a few problems, but this one, I did not expect!

I just could not FTP anything from my FedoraCore box. I checked the source system firewall, tweaked all sorts of options in the vsftpd.conf file to no aval.

The error I was getting was this:

Mon Aug 11 21:31:57 2008 [pid 12033] CONNECT: Client "192.168.2.11"
Mon Aug 11 21:31:57 2008 [pid 12032] [alexis] OK LOGIN: Client "192.168.2.11"
Mon Aug 11 21:31:57 2008 [pid 12034] [alexis] FAIL DOWNLOAD: Client "192.168.2.11", \
               "{fullpath to}/ubuntu-8.04.1-server-amd64.iso", 0.00Kbyte/sec

I read that permissions could be wrong. Not the case.

The firewall has some REJECT and DROP rules. None of which would increase when I was getting the FAIL DOWNLOAD message.

The fact was that the FedoraCore system firewall was not accepting the connection. That's why it would fail. I thus opened the firewall a bit by adding a rule like this:

-A INPUT -i eth0 -p tcp -m tcp -s 192.168.2.1 -d 192.168.2.2 --sport 20 -j ACCEPT

Then it finally worked.

Note that I am using FTP in non-passive mode. This is important because I do not want to open "random" ports on my server. There is nothing to control that in vsftpd as far as I know. Which sucks. My company's FTP server will automatically change the firewall and open ports as required. Once the FTP connection ends, the port is closed in the firewall. This means the port is open only very temporarily.

Anyway, all that to say that the message FAIL DOWNLOAD blah means nothing when it could be telling you: could not connect to client. At least that way you'd know right away what's wrong.

Submitted by Alexis Wilke on Wed, 12/24/2008 - 23:13

Well... I knew that a firewall could generate a few problems, but this one, I did not expect!

I just could not FTP anything from my FedoraCore box. I checked the source system firewall, tweaked all sorts of options in the vsftpd.conf file to no aval.

The error I was getting was this:

Mon Aug 11 21:31:57 2008 [pid 12033] CONNECT: Client "192.168.2.11"
Mon Aug 11 21:31:57 2008 [pid 12032] [alexis] OK LOGIN: Client "192.168.2.11"
Mon Aug 11 21:31:57 2008 [pid 12034] [alexis] FAIL DOWNLOAD: Client "192.168.2.11", \
               "{fullpath to}/ubuntu-8.04.1-server-amd64.iso", 0.00Kbyte/sec

I read that permissions could be wrong. Not the case.

The firewall has some REJECT and DROP rules. None of which would increase when I was getting the FAIL DOWNLOAD message.

The fact was that the FedoraCore system firewall was not accepting the connection. That's why it would fail. I thus opened the firewall a bit by adding a rule like this:

-A INPUT -i eth0 -p tcp -m tcp -s 192.168.2.1 -d 192.168.2.2 --sport 20 -j ACCEPT

Then it finally worked.

Anyway, all that to say that the message FAIL DOWNLOAD blah means nothing when it could be telling you: could not connect to client. At least that way you'd know right away what's wrong.

Submitted by Alexis Wilke on Wed, 12/24/2008 - 23:13

Well... I knew that a firewall could generate a few problems, but this one, I did not expect!

I just could not FTP anything from my FedoraCore box. I checked the source system firewall, tweaked all sorts of options in the vsftpd.conf file to no aval.

The error I was getting was this:

Mon Aug 11 21:31:57 2008 [pid 12033] CONNECT: Client "192.168.2.11"
Mon Aug 11 21:31:57 2008 [pid 12032] [alexis] OK LOGIN: Client "192.168.2.11"
Mon Aug 11 21:31:57 2008 [pid 12034] [alexis] FAIL DOWNLOAD: Client "192.168.2.11", \
               "{fullpath to}/ubuntu-8.04.1-server-amd64.iso", 0.00Kbyte/sec

I read that permissions could be wrong. Not the case.

The firewall has some REJECT and DROP rules. None of which would increase when I was getting the FAIL DOWNLOAD message.

The fact was that the FedoraCore system firewall was not accepting the connection. That's why it would fail. I thus opened the firewall a bit by adding a rule like this:

-A INPUT -i eth0 -p tcp -m tcp -s 192.168.2.1 -d 192.168.2.2 --sport 20 -j ACCEPT

Then it finally worked.

Anyway, all that to say that the message FAIL DOWNLOAD blah means nothing when it could be telling you: could not connect to client. At least that way you'd know right away what's wrong.

reCATPCHA for Drupal

It took me a little time, but I finally search and found the reCAPTCHA.

The default CAPTCHA for Drupal looks awful. It is called Image and creates very ugly extremly hard to read images. So I always wanted to switch to reCAPTCHA that is not perfect but looks a lot better and has audio availbale.

So today I found it, it is here: http://drupal.org/project/recaptcha

Note that you still need the CAPTCHA system, it just adds one more option which is reCAPTCHA instead of Image. (at leat, that the way I use it.)

Microsoft Word 2007 and Nested Lists

Today I decided to write a document for a customer about some work I have done for them.

I thought it would be a good idea to use Microsoft Word on the system I'm using for the development. It is from Office 2007.

Not too surprised that things look all different since I used MS-Access for a while now and it has this same new "weird" look.

What I ran into, however, is a wall when it came to creating styles with nested lists. You know, a usual document with points:

1.
1.1
1.2
1.2.1
1.2.2
2.
2.1
2.2
etc.

And I could create lists, but not nested lists. In other ...

The White Screen of Death

White Screen of Death

Using Drupal happily and all of a sudden... nothing! A completely blank page, often called the White Screen of Death or WSOD.

Quite annoying situation, I have to say, but well... it happens.

There are several (many?) pages about the White Screen of Death (in reference to the Blue Screen of Death by our friend Microsoft.)

[toc hide:1]

URL limits in browsers location bar

I thought it was interesting to see that some people actually tested the length of URLs in different browsers. You have to know that the size of a URL in the location bar may be differently limited than the length of the URLs you can go to with the browser (i.e. the URL in an anchor may need to be shorter! Or could be longer and still work.)

Note: These are Browsers limits in 2006.

List Open Files

This is a quick note so I can find the command I need to use to list open files.

My search will work this time.

lsof stands exactly for "LiSt Open Files"

That gives you a list of all the files opened by your system, process by process. It can be useful to know if you are developing a program or if you are limited in the number of files opened at once.

I spent hours today to find this one module: Rules.

In most cases, you can set up a rule in Drupal with their Actions and Triggers and it will work just fine. The fact is that these options are extremely limited if you want any kind of condition on the Rule before triggering the action.

The idea is very simple:

1. Something happens

2. Check whether it is of interest1

3. Trigger the action

I needed that functionality for a couple of websites because I wanted to get an event whenever someone created a new page, but not for any type of ...

1. This part is what is missing in Drupal Core v6.x

Samba & PAM

Since I installed Samba on my Linux box, I get many errors. From root kit checkers that tell me the port is deadly infected (no kinding!) to PAM that every day would tell me that the /lib/security/pam_smbpass.so module could not be found.

Oh! Yeah! I actually had to install that module. Not too obvious from the error though. I thought it would be automatic.

Every time a Windows box would connect, I'd get this entry:

May 17 07:05:01 hostname CRON[14871]: PAM unable to dlopen(/lib/security/pam_smbpass.so)
May 17 07:05:01 hostname CRON[14871]: PAM [error: /lib/security/pam_smbpass.so:

MS-Access defines many different types, including a newer one called DECIMAL.

You are supposed to be able to create tables with the DECIMAL type. So a statement such as:

   CREATE TABLE MyTbl (decimal_test DECIMAL(20, 5))

should work. Right?

I have been using CurrentDb.Execute for a while and that statement was causing the Execute function to return an error saying that the field definition was erronous (Syntax error in field definition, to be exact).

The trick is very simple!

Unfreeze your Mouse when it Froze

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