dpkg-reconfigure keyboard-configuration

If the kernel has not yet the capability of of handling exFAT filesystem here is how to add it as a user space capability in a Debian/Ubuntu system: sudo -s apt-add-repository ppa:relan/exfat apt-get install fuse-exfat

There are many ways to create Chroot for SSH here are 2 good links for that. http://www.debian.org/doc/manuals/securing-debian-howto/ap-chroot-ssh-env.en.html http://www.howtoforge.com/chrooted_ssh_howto_debian Note: Here some more info on the subject. The following article is based on an extract of the following site: http://www.howtoforge.com/restricting-users-to-sftp-plus-setting-up-chrooted-ssh-sftp-debian-squeeze Enabling chrooted SSH Enabling chrooted SSH is a bit complicated because we must set up a …

In order to turn OFF security checks in SSH connections set the folwoing configuration in the SSH server in /etc/ssh/sshd_config: UserKnownHostsFile=/dev/null StrictHostKeyChecking=no LogLevel=error This will also work if key forwarding is set as well.

This article is based on the following link of which I’m really thanful: https://paraaether.wordpress.com/2012/09/08/mount-exfat-filesystems-under-linux-mint-ubuntu/ Problem: Lately a new file system format meant for external flash-memory cards, Camera ssd cards and Smart phones is been develloped by Microsoft called ‘extFAT’. It allows to overcome the barrier of 4GB for single files and is more efficient for …

This message is flooding my syslog on each snmp query. snmpd[3916]: error on subcontainer ‘ia_addr’ insert (-1) snmpd[3916]: error on subcontainer ‘ia_addr’ insert (-1) snmpd[3916]: error on subcontainer ‘ia_addr’ insert (-1) To avoid it you have to change the log level of the services. In debian squeeze edit /etc/default/snmpd and change these lines: SNMPDOPTS=’-Lsd -Lf …

Although there are many tutorials concerning encrypting files sometimes one wants just to encrypt/decrypt files with only a passphrase. This what this article is about. This article is based on the great tutorials found at: http://bitflop.com/document/86. For a fuller Tutorial on GnuPG: http://bitflop.com/document/129 Thanks to the author for the good work. GnuPG Encryption: $ gpg …

Following a problem I had when trying to checkout old files from CVS repository I found out how to display the hex value of certain characters and how to convert them as well. Most older filenames have been encoded with the character set ISO-8859-1(latin-1) or ISO-8859-2(European) or ISO-8859-15(European+EURO sign). Mopst new systems are working with …

To erase files recursively in a specific directory with best security and make it almost impossible to recover any of the files in that directory, run the following command: cd /dir/where/to/delete/files/ find . -type f | while read file ; do shred –verbose –remove –zero -n 10 $file ; done I say almost because the …

Reference: This a complete ‘copy’ of the very useful info page at this link: http://www.pc-professionals.com/blog/cloning-a-linux-heartbeat-3-node/ Some heartbeat problems when starting: While setting up a Linux Heartbeat failover cluster, you may be tempted to set up one server node and clone the machine to create the other nodes that will make up your cluster. This is …

To display the UUID of all the found partitions in system and their /dev/… equivalent issue the command: ls -l /dev/disk/by-uuid/

Here are the instructions on how to install an efficient Linux remote desktop (XCFE) using VNC. apt-get install xorg xfce4 xfce4-goodies vnc4server Note: If you want to change the initial VNC port edit the file: /usr/bin/vnc4server and change the port as follows: eg. to change the vnc ports to start at 8081 ‘$vncPort = 8080 …

Command: /usr/bin/clamscan -r -i /start/directory

Problem Description: Although it can happen very rarely sometimes the dpkg, run by apt-get or aptitude, gets confused and leaves the lock on the mounting of its database open after being terminated. This prevents any further operations on installing, updating or configuring packages. The error would look like this: debconf: DbDriver “config”: /var/cache/debconf/config.dat is locked …

Often when seeting-up a VPN or other similar mechanism we need to transfer securely a private key or a list of passwords or anything very private to another party via email without running the risks of the man-in-the-middle snoopin on it. Here is a method using OpenSSL which is available in Linux. Sending a one …

In order to find out where the domain resolving fails here are some tricks using the command dig to trace the recursion step by step till the DNS that fails to deliver the IP of the requested [sub]domain. Reference site: https://nsrc.org/workshops/2005/pre-SANOG-VI/bc/dns/dns2-02-dig-debug.html Tracing a well resolving domain: So first we start by asking one of the …

Task: Keep multiple web server’s htdocs files in sync. One way to do it is to write a script as cronjob which synchronizes the main server’s configuration directories to all other servers. But there are more elegant ways to do it: GlusterFS and lsyncd. This article relates to the later: lsyncd This deamon process uses …

I’ve got a project where we needed to make sure the user had to be authenticated against Windows Active Directory. This is what helped me. Install the LDAP tools: (Example in Debian) apt-get install ldap-utils Command to authenticate Note: the user(Username) registered in Active Directory DN(DC=ad,DC=domain,DC=net). (Return code of command should be 0 if successful) …

Sometimes I try to unmount a storage device and it says that it cannot unmount because a process is using it. Now how to find this/these processes and kill them so I can unmount the device? Here is one way to do it. Long and careful way, step by step: # Find out the mount …

In some situations if one needs to change the MAC address of an ethernet card here is the way: ifconfig eth0 down ifconfig eth0 hw ether [new mac address] ifconfig eht0 up ifconfig eth0 And see you brand new ethernet address. have fun hacking 🙂

Problem: Lately I had the problem that some users could not log-in into their webmail(Squirrelmail). Squirrelmail answered: “ERROR: Connection dropped by IMAP server”. Looking into the logs I found the following lines: Jul 5 10:39:43 ms41 dovecot: imap-login: Login: user=user1>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured Jul 5 10:39:43 ms41 dovecot: IMAP(user1): mail_location not set and autodetection …

Introduction: This HOW-TO will describe with very few explanations how to minimally configure Heartbeat software for the purpose of automatically switching a virtual IP from one server to another when the default server fails. Here a ‘Virtual IP’ will be switched from one server to another depending on which one is available. Install heartbeat: apt-get …

Here are simple steps on how to dist-upgrade a Debian system using an ISO file. Normally the process would be quite simple by replacing the entries in the repository list and call a command apt-get update; apt-get disp-upgrade. BUT what if your system doesn’t have Internet acccess while you want to do the upgrade? Here …

Distro URL Command ====== ======================== ============================ Debian (http://www.debian.org) apt-get install packagename Ubuntu (http://ubuntulinux.org) apt-get install packagename Suse (http://www.opensuse.org) yast -i packagename Fedora Core (http://fedoraproject.org) yum install packagename FreeBSD (http://www.freebsd.org) pkg_add -r packagename Gentoo (http://www.gentoo.org) emerge packagename OpenBSD (http://www.openbsd.org) pkg_add -r packagename

Introduction: Imagine you have rented a system at a provider where you want to install remotely a totally new Debian Squeeze from scratch. You will need the following components: – A Remote KVM Switch where you can view and control the system via a console remotely. – A knoppix or any relatively recent bootable live …

In the case we absolutely need to install a special Debian package, from backports for example, and force it to ignore dependencies using aptitude download and dpkg –force-depends, your apt-get and aptitude will always complain later on about it and not resume its given commands until we resolve this dependency. So when you know what …

This short how-to shows how to find out a string length in bash: Copied from the very useful web site: http://unstableme.blogspot.com/2008/03/find-string-length-bash.html Suppose: $ VAR=”Bash Scripting” Now to find the length of the above string, I have found 3 different ways: $ echo “${#VAR}” 14 $ expr length “$VAR” 14 $ echo $VAR | awk ‘{print …

Here is an example of how to compile and install the latest SVN system in Debian. At the time of writing the latest stable version was 1.6.17. Because this method contains all the dependencies of SVN compiling, it can probably be used in many types of Linux distributions. Here are only commands to run as …

Unfortunately as of today June 19, the repository drivers of Wireless Broadcom BCM4313(wl.ko) don’t work well at all in Linux Mint 11. After making some research on Google I found out that there are new Linux drivers provided by the manufacturer Broadcom that simply need to be downloaded and installed. I did it and it …

Although the Linux Kernel has already a load-balancing feature, it doesn’t come without the price of having to learn how to use it. Some tools like ‘LVS-KISS’ can help to do that job but still a bit too much sometimes when one want just crude load-balancing without any fall-back features. Here is a simple solution …

Sometimes we want to install a package that is in testing state into a stable system. To do so, just follow the instructions below. NOTE: The following tips have been copied from the link: http://forums.spry.com/debian/620-how-install-testing-packages-debian-stable-apt-get.html The solution for keeping stable and installing the package is to modify apt-get configuration to setup what is called a …

What a disaster to find that your File Allocation Table is been destroyed. Well there is a possible light at the end of the tunnel. Scenario: Partition to recover: /dev/sdb2 HOW-TO – Find out where the SuperBlock got backed-up with the command mke2fs -n This gives you all the locations where the SuperBlock is back-up …

NOTE: This article is a copy of the Geek Stuff Article at: 10 Useful Sar (Sysstat) Examples for UNIX / Linux Performance Monitoring Tanks for the tips. I have copied it to make sure this important article stays part of this tips collection. Intro: Using sar you can monitor performance of various Linux subsystems (CPU, …

These following instructions will download, compile and install Bacula and a couple of the best Web GUIs for it. Inspired from the following German link. Thank you: http://www.asconix.com/howtos/debian/bacula-backup-debian-lenny-howto Install needed packages for Bacula server aptitude install build-essential libpq-dev libncurses5-dev libssl-dev psmisc mysql-server libmysql++-dev Download compile and install Bacuda and its web GUI wget http://downloads.sourceforge.net/project/bacula/bacula/5.0.3/bacula-5.0.3.tar.gz tar …