Blog entries from Andrea Benini

RAID: Installing grub on the other Disks

Andrea Benini — Wed, 23 Sep 2009 06:12:03 +0100

So, you've followed my previous blog: Replacing faulted drive on Linux software RAID (MDTOOLS), you already know how to swap a faulty drive with a new one, but what happens if you need to substitute primary disk where your Computer makes boot ?

After adding a new disk to your raid chain it's a good idea to make it bootable as well by installing grub on MBR. When boot drive in your raid array becomes faulty all you've to do is to power off your machine, substitute your faulty drive and bRead More...

Replacing faulted drive on Linux software RAID (MDTOOLS)

Andrea Benini — Tue, 08 Sep 2009 12:19:01 +0100

Here's a very quick HOWTO for Linux Software RAID, these notes are maded for replacing a faulty disk with a new one.

When you've a software RAID configuration with linux you've planned to survive to hardware failures, when these failures happen you need to replace the faulty drive with a new one and inform your RAID configuration of it.

First take a look at your current RAID config by running the command:

~# cat /proc/mdstat
Personalities : [raid1]
md1 : activeRead More...

One shot RSync between two hosts without installing services

Andrea Benini — Tue, 21 Jul 2009 11:47:25 +0100

I was syncing two Linux hosts, just need to copy data between them. I don't need and neither don't want to install Samba as a Service for a quick sync, RSync was my preferred method.

RSync is very easy to use and quick but in this case I don't either want to install RSync service daemon as well on the destination machine (the machine with data to transfer), so I've opted for rsync through ssh tunnel without a service installed.

Here's a quick sample:

- You've to transfer datRead More...

Samba public users directory (quick howto)

Andrea Benini — Fri, 17 Jul 2009 14:31:26 +0100

This quick post shows you how to create a samba share for a network, every user is forced to a specific username and each file belongs to this username. This is useful when dealing with public folders for some sort of exchange between users in a network

Read/Write access to everyone for directories and files, this is a tipical configuration for a swap area

Check it out:

[public]
comment = Public folder for my network
available = yes
browseable Read More...

HOWTO: VMWare Server 2, Disable Web Server Interface

Andrea Benini — Wed, 15 Jul 2009 13:11:49 +0100

Here I am, back again with episode 2 of VMWare Server, if you've already read HOWTO: Install VMWare Server 2, I guess you've a linux server with VMWare 2 up and running.

First thing I did after my installation was to reboot the machine to see memory usage and look at security issues. With no surprise I've seen Virtual Infrastructure Web Access enabled and when using netstat -a to see opened ports I've seen few more ports opened by VMWare webserver interface (apache tomcat and catalina fRead More...

HOWTO: Install VMWare Server 2 on Debian Lenny, AMD64 (64bit)

Andrea Benini — Tue, 14 Jul 2009 08:20:11 +0100

Intro

Everybody knows about VMWare Server, now with stable 2.x version my favorite feature is 64bit host native support.

I don't need to run guest 64bit OSes (yet) but 64bit native support is fine if you've a recent CPU and you'd like to take advantage of new servers outta there, and most important you can use a stable and working real 64bit application on your 64bit Debian system.

I've just installed a Debian Lenny (v5.0) host with AMD64 flavor, so a 64bit compiled OS on a brand Read More...

Disable IPV6 on Debian Lenny (quick howto)

Andrea Benini — Mon, 13 Jul 2009 08:50:39 +0100

Here's a very quick howto on disabling IPV6 on Debian (Lenny), this is not a new argument and neither an unknown solution, it's just how to disable IPV6 on Debian with less impact as possible on your machine config in "the debian way".

Sometimes you don't need IPV6: you've an already existing IPV4 net and you're happy with it, you don't want to waste memory or cpu cycles, you'd just like a very basic networking and setup.

There're a lot of way to do this, this mode is more "Read More...

WebServices Wars: "The Phantom Menace": Creating the WebService WSDL file

Andrea Benini — Fri, 03 Jul 2009 06:11:24 +0100

WebServices Wars: "The Phantom Menace": Creating the WebService WSDL file
Now if you've followed the introduction "WebServices Wars: Creating a basic webservice using Eclipse, php and apache" you're now ready for Episode I

IntroThis webservice saga begins with the base of every good project: the planning and design phase.
Here's what I'm going to do:
Create a WSDL definition file for the new service, it will be called sample.wsdl, it will be accessible from the followinRead More...

WebServices Wars: Creating a basic webservice using Eclipse, php and apache

Andrea Benini — Thu, 02 Jul 2009 10:00:08 +0100

Here I am,
That's a lot of time since my last blog, well, I was quite busy with something else (still have my private life ok ?) but now I'm back again with WebServices, PHP, Eclipse, Apache.

A lot of folks are asking me about some sort of short howto/sample/easy doc for dealing with webservices and php, there's a lot of information spread all around the web so I've decided to collect information from my projects and write down some notes for a quickstart howto with webservices andRead More...

SSH from your cell phone ? Here's Putty for Symbian

Andrea Benini — Thu, 11 Jun 2009 07:00:00 +0100

Few days ago I've heard about a Symbian port of Putty, obviously you alread know what putty is and what you can do with an SSH terminal emulator.

I think it's one of my favorite software pieces for Win32 machines, now there's a project aimed to port putty on Symbian OS machines, I've tried to install it into my samsung phone even if it's not supported or mentioned, results: clear, it doesn't work but the project seems promising.

At this url:
http://s2putty.sourceforge.net/

WGet and Downloading an entire remote directory

Andrea Benini — Wed, 10 Jun 2009 07:00:00 +0100

Sometimes you need to retrieve a remote url (directory) with everything inside it, when you miss a live presentation or a forum you often find material published on the web in a certain site; you'd like to get the entire presentation (usually several html pages and links) or read it online.

When no "download all" button is available or when you don't have spare time to read it immediately you wish to grab all the directory content and read it offline later, I usually downloadRead More...

Disable/Enable ping response on a Linux machine

Andrea Benini — Tue, 09 Jun 2009 07:00:00 +0100

Few days ago I was dealing with SYSCTL (man sysctl) utility and I was looking for a certain kernel parameter, I wish to set it on the fly and I've found other useful information too.

sysctl is used to modify kernel parameters at runtime, one of these parameter could be ping daemon response, if you want to disable ping reply on your network you just simply need to issue something like:

~# sysctl -w net.ipv4.icmp_echo_ignore_all=1
net.ipv4.icmp_echo_ignore_all = 1
(root acRead More...

Debian, Upgrading to Lenny, ERROR, no public key available for the following...

Andrea Benini — Mon, 08 Jun 2009 19:55:00 +0100

I've spent one day crushing my head against a weird problem, never seen it on Debian, I was only updating four Debian "etch" to "lenny" and in two of them I've seen this:

han:~# apt-get update
...
...
Fetched 74.7kB in 0s (87.4kB/s)
Reading package lists... Done
W: There is no public key available for the following key IDs:
9AA38DCD55BE302B
W: GPG error: http://xxx.xx.xxx.org lenny Release:
The following signatures couldn't be verified because the puRead More...

File transfer with Netcat

Andrea Benini — Mon, 08 Jun 2009 19:27:00 +0100

There's a basic usage for netcat helping you to transfer data/files across hosts without ssh or ftp services

Here's what I usually do on server (example IP: 1.2.3.4)

nc -l -p 6666 | uncompress -c | tar xvfp -

Basically I open TCP port 6666 (or whatever you want) on server and listen for raw compressed data

On my client I need to issue a command like this

tar cpf - /my/cool/dir | compress -c | nc -w 3 1.2.3.4 6666

Where /my/cool/dir is what I want toRead More...

Shared Samba Printer for PDF/PS Storage

Andrea Benini — Mon, 08 Jun 2009 07:00:00 +0100

As many of you already know I'm experiencing some sort of hylafax/samba integration for a mixed Windows environment, this blog is for creating a PDF/PostScript printer easily, no matter of what you do with the printer; when you print on it you'll produce a Postscript/PDF document

requirements:
A samba server installation up and running

achievements:
Create a PostScript/PDF document from a spool so every Windows user in your net can generate documents without client sideRead More...

Spammers out from this Blog Area

Andrea Benini — Thu, 04 Jun 2009 07:00:00 +0100

As many of you I've decided to stop using this blog area until spam ends in this zone.

When linux.com renewed its layout I've used the Blog area to read opinions from other users and even publish some tech hints useful for myself and hopefully useful for someone else as well. I've sent few hints and some usernames to linux.com managers and they've replied back with appreciations for it.

They're now implementing a new spam filter as well as other things to keep spammers out and avoRead More...

Swapping STDOUT and STDERR under Bash Shell

Andrea Benini — Wed, 03 Jun 2009 07:00:00 +0100

I usually forgot this simple command so I've decided to write down some notes on it so I can cut 'n' paste from here easily, here's another common question:

"How to swap stdout and stderr descriptors ?"

This enables your scripts to parse stderr and forget stdout (or redirect it to a file)

Here's:

command <parameters> 3>&1 1>/dev/null 2>&3-

Here's what it does:

Moves stdout to /dev/null (or your preferred file if neededRead More...

Find a string in files (using grep easily)

Andrea Benini — Wed, 03 Jun 2009 07:00:00 +0100

Here's a quick command for a quite common problem:

Is there a way to find a text string inside a bunch of files in a dir ?

Sure it is, here's one :

grep 'MyCoolString' /my/preferred/directory/*

Searches "MyCoolString" inside the specified path and willcard, or if you prefer to ignore case take a look at:

grep -i 'mycoolstring' /my/preferred/directory/*

Easy isn't it ?

Obviously this is not the only method but it's my preferred one, eRead More...

Debian: Find package name from program name

Andrea Benini — Wed, 03 Jun 2009 07:00:00 +0100

Back again,
This time it's Debian's time, when managing multiple hosts and installations sometimes happens you need to know what package owns a certain utility.

Recently I've faced a quite common problem, I'll take it as an example so it's more clear, I had a common and popular program "pdftotext" and I wanted to have it into another debian installation, quite easy isn't it ? you only need to remember what package has it.

While fighting with Ghostscript program andRead More...

Hylafax, send a fax from the command line

Andrea Benini — Wed, 27 May 2009 07:00:00 +0100

In these days I'm stressing hylafax a lot, I think it's a nice and powerful program, stable, complete and reliable. When my job will be completed I'll publish some thoughts about it.

Server part is so stable and secure, client part, expecially for Windows clients have some lacks, there're a lot of win client all around but every software I've tried has some lacks so as a lot of you I've decided to write my own.

Few of them have everything I need, except the license and price, I meRead More...