Category Archives: unix

RTL8723BE realtek wifi chipset to work on ubuntu 14.04 [solved]

This wifi chipset is quite new and not working out of the box. Steps to get it work: ensure you have the appropriate chipset: lspci | grep RTL8723BE 02:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter compile and load specific driver by running following commands: sudo apt-get install linux-headers-generic build-essential git git clone http://github.com/lwfinger/rtl8723be cd rtl8723be git checkout 604aa9058fb9e5bb1cf571c99989d081f8fc8b9 make sudo make install sudo modprobe rtl8723be That’s it! For me it worked like charm. sources http://ubuntuforums.org/showthread.php?t=2205497

run virtualbox on kimsufi server

Just bought a low-end kimsufi server (atom D425) and tried to run virtualbox on it. Host os is Ubuntu Desktop 14.02 Proceed as follow revert to Ubuntu stock kernel instead of tweaked ovh one: [UPDATE: ignore this section, rather simply use advanced mode when installing distribution and select to use native distribution kernel] sudo apt-get install linux-image-server mkdir ~/ovh.d/ sudo mv /etc/grub.d/06_OVHkernel ~/ovh.d sudo update-grub sudo apt-get install linux-headers-generic restart machine sudo shutdown -r -f now install virtualbox //sudo apt-get install virtualbox // update: do not do this since version in ubuntu repository is quite old, download from www.virtualbox.org instead […]

xml indentation in linux

XML beautifier in linux can be easily done using libxml tools. install xml library sudo apt-get install libxml2-utils Run the following command xmllint –format –output <path_to_output> <input_file> That’s it! Apparently this tool can be used for smooth integration within gedit but this made gedit crash on my computer. sources http://www.andrejkoelewijn.com/blog/2012/04/11/formatting-xml-documents-with-gedit-and-tidy/ http://andalinux.wordpress.com/2011/11/21/pretty-printer-de-xml-en-gedit/ http://andalinux.wordpress.com/2010/07/19/gedit-avanzado-ejecutar-scripts-desde-el-editor/

linux mint – unable to mount mtp device [solved]

When I tried to connect my android phone to linuxmint16 64bits, I got popup error messages: Could not display “mtp://[usb:003,021]/” Error: no such interface ‘org.gtk.vfs.Mount’ on object at path /org/gtk/vfs/mount/1 Please select another view and try again. Followed by: Unable to open MTP device ‘[usb:003,029]’ To correct this, make sure following packages are installed sudo apt-get install mtpfs mtp-tools Update: above did not solved the issue sources http://community.linuxmint.com/software/view/mtp-tools http://community.linuxmint.com/tutorial/view/1185

listen to any port / sniff any tcp port – linux

Here is a very nice package to listen to tcp ports: sudo apt-get install tcpflow To activate it, run: sudo tcpflow -i any -C -e port XXXX Options may vary based on version of the tool. tcpflow -h for more details sources http://superuser.com/questions/23180/whats-the-easiest-way-to-sniff-tcp-traffic-data-on-linux

Oracle XE 11g R2 – activate audit / log queries

To log queries on oracle, proceed as follow: login as system (`sqlplus system`) check audit status show parameter AUDIT_TRAIL; // if NONE => no audit activated activate audit ALTER SYSTEM SET AUDIT_TRAIL=DB SCOPE=SPFILE; restart db for parameter to take effect /etc/init.d/oracle-xe restart from this point forward, activate audit on specific tables and/or actions and/or users using the AUDIT XXX statement, as `system`, run: AUDIT SELECT on userlambda.tablename // audit/log all SELECT queries on all tables db for user userlambda All audit entries are stored under sys.AUD$ table (login as system to access it). Note: to deactivate audit, run ALTER SYSTEM […]

install oracle sqlplus client – linux

When trying to get sqlplus client running, following error was generated: sqlplus: error while loading shared libraries: libsqlplus.so: cannot open shared object file: No such file or directory This happens because environment variable LD_LIBRARY_PATH was empty. Make it point to ./lib folder where sqlplus client was extracted and this should solve the problem. In my case, oracle sqlplus client was generated under /opt/oracle LD_LIBRARY_PATH=/opt/oracle/bin export LD_LIBRARY_PATH And voila! sources http://betterlogic.com/roger/2010/11/how-to-install-sql-plus-in-linux/

monitor files being accesssed

There is a great tool to identify files being access: inotifywait steps make sure inotify package is installed sudo apt-get install inotify-tools simply run inotifywait -m -r –format ‘%:e %f’ . all files being accessed will be displayed Additional filtering and output formatting options are available, `man inotifywait` for more information. Note that inotifywatch is also available, no monitor files for a given timeperiod. examples //1. listen to all events on all files (recursively) within current directory with output of type “EVENT_TYPE file_name” inotifywait -m -r –format ‘%:e %f’ . // 2. listen to event MODIFY (i.e. writing content) on […]

centos 5 – virtualbox guest additions fail to compile [solved]

Installing virtualbox guest additions was not really smooth. To ensure successful installation, make sure of the following: kernel-devel and kernel-headers must be installed for your current kernel version (reboot after installing) yum install *kernel-devel* *kernel-headers* make sure they match version returned by `uname -r` Note1: if you installed centos from iso, rpms are already on the iso under /CentOS folder (=> not need to download them and they will match installed kernel if you did not update it) Note2: to install these packages, do add GPG_KEY for centos5 packages via running rpm –import http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-5 although here again, GPG_KEY file is […]

can’t connect to X11 window server using ‘:0.0’ as the value of the DISPLAY variable [solved]

When running some dodgy software, I ended up on below error: can’t connect to X11 window server using ‘:0.0’ as the value of the DISPLAY variable I tried different values for $DISPLAY, with and without ip-address, no success. Command `xhost +` also returned error message: xhost: unable to open display “:0.0” Steps to solve this problem were as follow: Running `ps aux | grep X` returned following output: /usr/bin/Xorg :0 -br -verbose -nolisten tcp -audit 4 -auth /var/run/gdm/auth-for-gdm-NZACr6/database To get rid of -nolisten tcp option, which prevent remotely login on X server, option DisallowTCP must be set to false. Running […]