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How to install Toshiba Satellite L40 B14 Wireless Adapter ( ID 0bda:8197 Realtek Semiconductor Corp. RTL8187B) on Ubuntu and Debian Linux

Thursday, April 28th, 2011

https://www.pc-freak.net/images/toshiba-satellite-l40

How to install Toshiba L40 B14 Wireless Adapter ( ID 0bda:8197 Realtek Semiconductor Corp. RTL8187B) on Ubuntu and Debian Linux
I've been struggling for more than 10 hours to fix up issues on a Ubuntu Maverick-Meerkaat with a rtl8187B Wireless Adapter

The RTL8187B almost drove me mad. I could see the wlan0 which meant the kernel is detecting the device, I could even bring it up with ifconfig wlan0 up , however when I tried it in gnome's network-manager or wicd the wireless networks were not showing up.

Trying to scan for networks using the commands:


ubuntu:~# iwlist wlan0 scan

was also unsuccesful, trying to bring up and down the wireless wlan0 interface with:


ubuntu:~# iwconfig wlan0 up

or


ubuntu:~# iwconfig wlan0 down

Both returned the error:
iwconfig: unknown command "up" and iwconfig: unknown command "down"

Running simply iwconfig was properly returning information about my Wireless Interface wlan0 :


wlan0 IEEE 802.11bg ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=20 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off

The exact information I could get about the wireless device was via the command:


ubuntu:~# lsusb | grep realtek
Bus 001 Device 002: ID 0bda:8197 Realtek Semiconductor Corp. RTL8187B Wireless Adapter

Trying manually to scan for wireless networks from console or gnome-terminal with command returned also the below weird results:


ubuntu:~# iwconfig wlan0 scan
iwconfig: unknown command "scan"

More oddly tunning wlan0 interface with commands like:


ubuntu:~# iwconfig wlan0 mode managed
ubuntu:~# iwconfig wlan0 essid ESSID
ubuntu:~# iwconfig wlan0 rate 11M

were succesful …

I read a bunch of documentation online concerning the wireless card troubles on Ubuntu, Gentoo, Debian etc.

Just few of all the resources I've read and tried are:

http://rtl-wifi.sourceforge.net/wiki/Main_Page (Returning empty page already a lot resource)
http://rtl8187b.sourceforge.net (A fork of rtl-wifi.sourceforge.net which is still available though it was not usable)

Some of the other resources which most of the people recommended as a way to properly install the RTL8187B wireless driver on linux was located on the website:

http://datanorth.net/~cuervo/rtl8187b/ (Trying to access this page returned a 404 error e.g. this page is no-longer usable)

I found even a webpage in Ubuntu Help which claimed to explain how to properly install and configure the RTL8187B wireless driver on which is below:

https://help.ubuntu.com/community/WifiDocs/Device/RealtekRTL8187b

Even the Ubuntu help instructions were pointing me to the broken cuervo's website URL

Anyways I was able to find the rtl8187b-modified-dist.tar.gz online and made a mirror of rtl8187b-modified-dist.tar.gz which you can download here

Another rtl8187b driver I found was on a toshiba website made especailly for the wireless linux drivers:

http://linux.toshiba-dme.co.jp/linux/eng/pc/sat_PSPD0_report.htm

The questionable file which was claimed to properly be able to make the Realtek Semiconductor Corp. RTL8187B Wireless Adapter to work out was called rl8187b-modified-804.tar.gz.
I've made a mirror of rtl8187b-modified-804.tar.gz is here

None of the driver archives rtl8187b-modified-dist.tar.gz and rl8187b-modified-804.tar.gz that was supposed to make the Toshiba L40 realtek wireless to work out, after compiling and installing the drivers from source worked out …

Both archives produced plenty of error messages and it seems on newer kernels like the one on this notebook:

Linux zlatina 2.6.35-28-generic #50-Ubuntu SMP Fri Mar 18 19:00:26 UTC 2011 i686 GNU/Linux, they're no longer usable.

The compile errors I got when I tried compiling the rtl8187b driver provided by the archive rtl8187b-modified-dist were:


root@ubuntu:/home/zlatina/rtl8187b-modified# sh makedrv
rm -fr *.mod.c *.mod *.o .*.cmd *.mod.* *.ko *.o *~
make -C /lib/modules/2.6.35-28-generic/build M=/home/zlatina/rtl8187b-modified/ieee80211 CC=gcc modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.35-28-generic'
scripts/Makefile.build:49: *** CFLAGS was changed in "/home/zlatina/rtl8187b-modified/ieee80211/Makefile". Fix it to use EXTRA_CFLAGS. Stop.
make[1]: *** [_module_/home/zlatina/rtl8187b-modified/ieee80211] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.35-28-generic'
make: *** [modules] Error 2
rm -fr *.mod.c *.mod *.o .*.cmd *.ko *~
make -C /lib/modules/2.6.35-28-generic/build M=/home/zlatina/rtl8187b-modified/rtl8187 CC=gcc modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.35-28-generic'
scripts/Makefile.build:49: *** CFLAGS was changed in "/home/zlatina/rtl8187b-modified/rtl8187/Makefile". Fix it to use EXTRA_CFLAGS. Stop.
make[1]: *** [_module_/home/zlatina/rtl8187b-modified/rtl8187] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.35-28-generic'
make: *** [modules] Error 2
root@ubuntu:/home/zlatina/rtl8187b-modified#

Another driver I tried which was found on aircrack-ng.org's website was rtl8187_linux_26.1010.zip

Here are the error messages I experienced while I tried to compile the realtek wireless driver from the archive rtl8187_linux_26.1010.0622.2006


compilation terminated.
make[2]: *** [/home/zlatina/rtl8187_linux_26.1010.0622.2006/beta-8187/r8187_core.o] Error 1
make[1]: *** [_module_/home/zlatina/rtl8187_linux_26.1010.0622.2006/beta-8187] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.35-28-generic'
make: *** [modules] Error 2
make: *** [modules] Error 2

I tried a number of fix ups hoping to solve the compile error messages, but my efforts were useless, as it seems many things has changed in newer Ubuntu versions and they could no longer be compiled.

As I realized I couldn't make the native drivers provided by the above sources compile, I decided to give a try to the Windows drivers for Realtek 8187B with ndiswrapper, a link for download of Realtek 8187B (RTL8187B_XP_6.1163.0331.2010_Win7_62.1182.0331.2010_UI_1.00.0179 is found here

I untarred the
RTL8187B_XP driver
and used ndiswrapper to load driver like so:


root@ubuntu:~# tar -zxvf
RTL8187B_XP_6.1163.0331.2010_Win7_....L.tar.gz
root@ubuntu:/home/zlatina/RTL8187B#
root@ubuntu:/home/zlatina/RTL8187B# cd Driver/WinXP
root@ubuntu:/home/zlatina/RTL8187B/Driver/WinXP# ndiswrapper -i net8187b.inf

In order to test the RTL8178B Windows driver I used:


root@ubuntu:~# ndiswrapper -l
net8187b : driver installed
device (0BDA:8197) present (alternate driver: rtl8187)

To finally load the Windows XP RTL8187B driver on the Ubuntu I used again ndiswrapper:


root@ubuntu:~# ndiswrapper -m

Further on I used the ndisgtk graphical ndiswrapper interface to once again test if the Windows driver is working on the Ubuntu and it seemed like it is working, however still my wicd was unable to find any wireless network ….

There were many online documentation which claimed that the driver for rtl8187b works out of the box on newer kernel releases (kernel versions > 2.6.24)

Finally I found out there is a driver which is a default one with the Ubuntu e.g. rtl8187.ko , I proceeded and loaded the module:


root@ubuntu:~# modprobe rtl8187

I also decided to check out if the hardware switch button of the Toshiba Satellite L40 notebook is not switched off and guess what ?! The Wireless ON/OFF button was switched OFF!!! OMG …

I switched on the button and wicd immediately started showing up the wireless networks …

To make the rtl8187 module load on Ubuntu boot up, I had to issue the command:


root@ubuntu:~# echo 'rtl8187' >> /etc/modules

Voila after all this struggle the wireless card is working now, it's sad I had to loose about 10 hours of time until I come with the simple solution of using the default provided ubuntu driver rtl8187 , what is strange is how comes that it does not load up automatically.

Thanks God it works now.

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Posted in Linux, Linux on Laptops, Various | 3 Comments »

How to Increase virtualbox Linux install machine VM .VDI hard disk size to free space on root partition – Move /usr to a new partition

Tuesday, October 10th, 2017

extend-vdi-virtual-machine-partition-with-virtualbox-howto-virtualbox-logo
 

How to Increse Hard Disk size of VirtualBox Virtual Machine .VDI file to Free Space on root Partition or Howto move /usr large partition to separate new partition?


I just wondered how to increase hard disk size of Virtualbox Virtual Machine image .VDI, because for some stupid reason I've created my initial hard disk size for Linux partition to be the default 10 Gigabytes.

The problem is the packages I need to have installed on the Virtual Machine which will be a testbed for future tests of a production website applications are taking up too much space, once installed so I'm left with no space
in /var/lib/mysql for the database import. So what can I do in that case is to simply free up disk space or Merge ROOT partition with another partition.

Since merging the partition is not a trivial job and would require me to have installable CD with the Linux distro (in my case that's Debian Linux) or have a bootable USB flash drive, I preferred second approach to problem e.g. to free up disk space on ROOT partition by creating a second partition and move the /usr folder to reside there.

Before that it is of course necessery to  have extended the .VDI file using VirtualBox, so more space than the default 10GB preconfigured are available, this is easily done on Windows OS as, VBox is provided with GUI clickable option to do it, but for who knows what reason that is not the case with Linux, so Linux users only option to increase VDI file is to manually run command part of the virtualbox package, that is not a hard task really but it requires some typing and basic knowledge on how to run commands in terminal.


To .VDI resize (extend), we first go to default location where VirtualBox stores its image .VDI files (by default as of moment of writting this article – this is ~/"VrtualBox VMs"  (or home directory of logged in user dir VirtualBox VMs), the command to use is VBoxManage

 

root@jericho:/home/hipo# cd VirtualBox VMs/
root@jericho:/home/hipo/VirtualBox VMs# ls
Debian 6  Debian 9  Windows 10
root@jericho:/home/hipo/VirtualBox VMs# cd Debian 6/
root@jericho:/home/hipo/VirtualBox VMs/Debian 6# ls
Debian 6.vbox  Debian 6.vbox-prev  Debian 6.vdi  Logs  NewVirtualDisk1.vdi  Snapshots
root@jericho:/home/hipo/VirtualBox VMs/Debian 6# VBoxManage modifyhd Debian 6.vdi –resize 20000
0%…10%…20%…30%…40%…50%…60%…70%…80%…90%…100%
root@jericho:/home/hipo/VirtualBox VMs/Debian 6#


 

Above command does resize the 10GB default created partition for Linux, where I have installed Linux which was 99% full of data, because of the many packages I installed to 20GB size, to make it bigger just use the respective size, be it 30000 (for 30GB) or 100000 (for 100GB) etc.

Even though in this example VBoxManage virtual partition resize command was done for GNU / Linux Operating System, it can be done for any other Operating as well to resize the size of the Virtual .VDI file (Virtual Machine) partition, be it Windows 7 / 8 / 10 or the rest of Free Operating systems FreeBSD / OpenBSD / BSD that are installed in a VM etc.

Next Launch the Virtual Machine with VBox Server client Program and install there Gparted (GNU Parted), as we'll need it to create a new Hard Disk Partition:

 

$ VirtualBox

 


Inside virtualmachine's in gnome-terminal / xterm etc. depending on the graphical environment used do install with apt-get:

 

debian:# apt-get install –yes gparted
…

 

debian~:# gparted


Notice that gparted has to be ran as a root superuser.

 

Run GParted and create new EXT3 filesystem that is 10GB (the size of the new created partition).

If you have installed Debian to place all partitions under / (root directory /dev/sda1) then the fresh new partition to create should be
/dev/sda3, anyways just look closely in EXT3 and in your case if the partiition is named differently create according to proper partition /dev/ naming.

I'll not run into details on how to create the partition with GParted as the program interface is very self-explanatory, the only thing is to apply the update to create partition and the ext3 filesystem, that's being done
with a green tick:

gparted-create-ext3-partition-howto-linux

Next step is to check with fdisk whether, we have ext3 properly created  filesystem as we've done already with GPARTED:

Once we have the partition created with EXT3 filesystem, we're ready to move /usr temporary to other folder, I use usually /root for the move but you can create anywhere a new folder for that and move to there.

To move to /root directory run again in terminal:

 

debian:~# mv /usr /root
debian:~# mkdir /usr

 

howto-extend-root-filesystem-disk-space-linux-move-usr-folder-to-root-temporary-debian-gnu-linux

 

Note that during the move operations, your Desktop icons will become without (with broken) pictures and the default Debian background picture is to disappear, that's because the GUI environment will soon realize /usr/ libraries that're periodically reloaded in memory are missing and will be unable to reload them as it does in a cycle.

That should take a few minutes, so grab a coffee or if you're a smoker (hope not as smoking kills 🙂 ), in 5 / 10 minutes time depending on your computer / server configuration, it will be over, so we're ready to create new /usr dir and mount the  new partition:

 

debian:~# mount /dev/sda3 /usr

 

howto-extend-root-filesystem-disk-space-linux-move-usr-folder-to-root-temporary-debian-gnu-linux1

 

Now we check with mount command whether mount is fine:

 

check-if-filesystem-is-properly-mounted-linux-debian-screenshot


Now  /dev/sda3 is mounted under /usr  and we have to move back /root/usr directory content back to the newly mounted /usr so we run command:
 

debian:~#  mv /root/usr/* /usr/*


Finally we need to create proper records for the new partition inside /etc/fstab (fstab –FileSystem Tab file – the file which describes instructs the Linux OS what partition to boot where, what)

HOW TO CHECK LINUX UUID FOR A PARTITION??

Before adding anything to /etc/fstab you need to check the UUID of /dev/sda3 (or whatever the partition is called), without proper UUID, the system might fail to boot.
So here is how to check the UUID we'll need for config:
 

hipo@debian:~$ /sbin/blkid /dev/sda3
/dev/sda3: UUID="2273db4b-3069-4f78-90fc-e7483c0305bd" SEC_TYPE="ext2" TYPE="ext3"

hipo@debian:~$ ls -al /dev/disk/by-uuid/
total 0
drwxr-xr-x 2 root root 100 Oct  6 05:16 .
drwxr-xr-x 6 root root 120 Oct  6 05:16 ..
lrwxrwxrwx 1 root root  10 Oct  6 05:16 2273db4b-3069-4f78-90fc-e7483c0305bd -> ../../sda3
lrwxrwxrwx 1 root root  10 Oct  6 05:16 b98d92cd-41aa-4e18-a474-9b8df445dbe5 -> ../../sda1
lrwxrwxrwx 1 root root  10 Oct  6 05:16 f27f7448-f200-4983-b54f-b9e5206f77ac -> ../../sda5

As you can see our /dev/sda3 UUID is 2273db4b-3069-4f78-90fc-e7483c0305bd

Further on lets view and edit /etc/fstab you can also download a copy of my Virtual Machine fstab here

 

debian:~# cat /etc/fstab

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
# / was on /dev/sda1 during installation
UUID=b98d92cd-41aa-4e18-a474-9b8df445dbe5 /               ext3    errors=remount-ro 0       1
# swap was on /dev/sda5 during installation
UUID=f27f7448-f200-4983-b54f-b9e5206f77ac none            swap    sw              0       0
/dev/scd0       /media/cdrom0   udf,iso9660 user,noauto     0       0
/dev/scd1       /media/cdrom1   udf,iso9660 user,noauto     0       0


We need to add following line to  /etc/fstab:
 

UUID=2273db4b-3069-4f78-90fc-e7483c0305bd    /usr        ext3 error=remount-ro    0    1

 


Open the file with your favourite text editor (gedit / nano / pico / vim / joe) etc.

debian:~# vim /etc/fstab

 

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
# / was on /dev/sda1 during installation
UUID=b98d92cd-41aa-4e18-a474-9b8df445dbe5 /               ext3    errors=remount-ro 0       1
# swap was on /dev/sda5 during installation
UUID=f27f7448-f200-4983-b54f-b9e5206f77ac none            swap    sw              0       0
/dev/scd0       /media/cdrom0   udf,iso9660 user,noauto     0       0
/dev/scd1       /media/cdrom1   udf,iso9660 user,noauto     0       0
UUID=2273db4b-3069-4f78-90fc-e7483c0305bd     /usr        ext3 error=remount-ro    0    1    

Basicly it should be possible to add (for historic reasons) also instead of UUID=2273db4b-3069-4f78-90fc-e7483c0305bd  /dev/sda3
So it looks like so but, the better practice is to use UUID line given.

Well that's all folks now /usr directory will contain all your heavy root partition (disk filling) libraries and files, so you can happily use /var/lib/mysql or /var/lib/postgresql /var/www to store your web application files and import your databases.

Big thanks to Ubuntu Forums article – How do I increase the hard disk size of the Virtual Machine article for inspiring this post.

Hope that helps anyone and thanks and other comments are always welcome ! 🙂

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Posted in Everyday Life, Linux, Linux and FreeBSD Desktop, System Administration, Virtual Machines | No Comments »

How to fully recover deleted files on ext3 Debian Linux partition – undelete files from ext3 filesystems with ext3grep

Monday, March 7th, 2011

In order to recover fully data by mistake or on purpose deleted on Debian GNU/Linux there is a tool called ext3grep which is able to completely recover data by innodes.

Recovering the deleted files data is very easy and can be done via some livecd after installing the ext3grep tool.

In my case I used the Back Track Linux distribution to recover my data. Recovery is still in process and it appears all or at least most of my data is about to be recovered.

For the recovery procedure all necessary is an external partition in ext3 or ext3 where the recovered data from the ext3 device can be stored.

My partition was about 20GB and since I had no external hard dive to store the data to I used the sshfs to mount remotely a hard drive via the networking using the sshfs program to make the ssh mount for more see my previous post Howto mount remote server ssh filesystem using sshfs

The Backtrack livecd linux security distribution is missing the ext3grep tool thus I had to first install the tool after booting the livecd on the notebook to succeed in that it was necessary to install the e2fslibs-dev package through the command:

debian:~# apt-get install e2fslibs-dev

Further on I've downloaded the latest version of the ext3grep and untarred the archive and compiled it with the commands:

debian:~# ./configure && make && make install
Then I used the simple commands:

debian:~# cd /mnt/res
debian:~# ext3grep --restore-all /dev/sda8

to launch the recovery.
Where in the above commands /mnt/res is the mountpoint location where I wanted to have all my data recovered and the /dev/sda8 is the device from which I wanted to recover my data.

It takes a bit long until the recovery is completed and with 20 gigabytes of data about 5, 6 hours might be necessary for the data to be recovered but the main point is it recovers.

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Posted in System Administration | 1 Comment »

Howto Fix “sysstat Cannot open /var/log/sysstat/sa no such file or directory” on Debian / Ubuntu Linux

Monday, February 15th, 2016

sysstast-no-such-file-or-directory-fix-Debian-Ubuntu-Linux-howto
I really love sysstat and as a console maniac I tend to install it on every server however by default there is some <b>sysstat</b> tuning once installed to make it work, for those unfamiliar with <i>sysstat</i> I warmly recommend to check, it here is in short the package description:<br /><br />
 

server:~# apt-cache show sysstat|grep -i desc -A 15
Description: system performance tools for Linux
 The sysstat package contains the following system performance tools:
  – sar: collects and reports system activity information;
  – iostat: reports CPU utilization and disk I/O statistics;
  – mpstat: reports global and per-processor statistics;
  – pidstat: reports statistics for Linux tasks (processes);
  – sadf: displays data collected by sar in various formats;
  – nfsiostat: reports I/O statistics for network filesystems;
  – cifsiostat: reports I/O statistics for CIFS filesystems.
 .
 The statistics reported by sar deal with I/O transfer rates,
 paging activity, process-related activities, interrupts,
 network activity, memory and swap space utilization, CPU
 utilization, kernel activities and TTY statistics, among
 others. Both UP and SMP machines are fully supported.
Homepage: http://pagesperso-orange.fr/sebastien.godard/

 

If you happen to install sysstat on a Debian / Ubuntu server with:

server:~# apt-get install –yes sysstat


, and you try to get some statistics with sar command but you get some ugly error output from:

 

server:~# sar Cannot open /var/log/sysstat/sa20: No such file or directory


And you wonder how to resolve it and to be able to have the server log in text databases periodically the nice sar stats load avarages – %idle, %iowait, %system, %nice, %user, then to FIX that Cannot open /var/log/sysstat/sa20: No such file or directory

You need to:

server:~# vim /etc/default/sysstat


By Default value you will find out sysstat stats it is disabled, e.g.:

ENABLED="false"

Switch the value to "true"

ENABLED="true"


Then restart sysstat init script with:

server:~# /etc/init.d/sysstat restart

However for those who prefer to do things from menu Ncurses interfaces and are not familiar with Vi Improved, the easiest way is to run dpkg reconfigure of the sysstat:

server:~# dpkg –reconfigure


sysstat-reconfigure-on-gnu-linux

 

root@server:/# sar
Linux 2.6.32-5-amd64 (pcfreak) 15.02.2016 _x86_64_ (2 CPU)

0,00,01 CPU %user %nice %system %iowait %steal %idle
0,15,01 all 24,32 0,54 3,10 0,62 0,00 71,42
1,15,01 all 18,69 0,53 2,10 0,48 0,00 78,20
10,05,01 all 22,13 0,54 2,81 0,51 0,00 74,01
10,15,01 all 17,14 0,53 2,44 0,40 0,00 79,49
10,25,01 all 24,03 0,63 2,93 0,45 0,00 71,97
10,35,01 all 18,88 0,54 2,44 1,08 0,00 77,07
10,45,01 all 25,60 0,54 3,33 0,74 0,00 69,79
10,55,01 all 36,78 0,78 4,44 0,89 0,00 57,10
16,05,01 all 27,10 0,54 3,43 1,14 0,00 67,79


Well that's it now sysstat error resolved, text reporting stats data works again, Hooray! 🙂

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Posted in Everyday Life, Linux, Linux and FreeBSD Desktop, Monitoring, Performance Tuning, Remote System Administration, System Administration, Various | No Comments »

Adding another level of security to your shared Debian Linux webhosting server with SuPHP

Tuesday, April 7th, 2015

suphp_improve-apache-security-protect-against-virus-internal-server-infections-suphp-webserver-logo

There are plenty of security schemes and strategies you can implement if you're a Shared Web Hosting company sysadmin however probably the most vital one is to install on Apache + PHP Webserver SuPHP module.

# apt-cache show suphp-common|grep -i descrip -A 4

Description: Common files for mod suphp Suphp consists of an Apache module (mod_suphp for either Apache 1.3.x or Apache 2.x) and a setuid root binary (suphp) that is called by the Apache module to change the uid of the process executing the PHP interpreter to the owner of the php script.

So what SuPHP actuall  does is to run separate CPanel / Kloxo etc. Users with separate username and groupid permissions coinciding with the user present in /etc/passwd , /etc/shadow files existing users, thus in case if someone hacks some of the many customer sites he would be able to only write files and directories under the user with which the security breach occured.

On servers where SuPHP is not installed, all  systemusers are using the same UserID / GuID to run PHP executable scripts under separate domains Virtualhost which are coinciding with Apache (on Debian / Ubuntu  uid, gid – www-data) or on (CentOS / RHEL / Fedora etc. – user apache) so once one site is defaced  exploited by a worm all or most server websites might end up infected with a Web Virus / Worm which will be trying to exploit even more sites of a type running silently in the background.  This is very common scenarios as currently there are donezs of PHP / CSS / Javasripts / XSS vulnerability exploited on VPS and Shared hosting servers due to failure of a customer to update his own CMS  scripts / Website  (Joomla, Wordpress, Drupal etc.) and the lack of resource to regularly monitor all customer activities / websites.

Therefore installing SuPHP Apache module is essential one to install on new serverslarge hosting providers as it saves the admin a lot of headache from spreading malware across all hosted servers sites ..
Some VPS admins that are security freaks tend to also install SuPHP module together with many chrooted Apache / LiteSpeed / Nginx webservers each of which running in a separate Jailed environment.

Of course using SuPHP besides giving a improved security layer to the webserver has its downsides such as increased load for the server and making Apache PHP scripts being interpretted a little bit slower than with plain Apache + PHP but performance difference while running a site on top of SuPHP is often not so drastic so you can live it up ..

Installing SuPHP on a Debian / Ubuntu servers is a piece of cake, just run the as root superuser, usual:
 

# apt-get install libapache2-mod-suphp


Once installed only thing to make is to turn off default installed Apache PHP module (without SuPHP compiled support and restart Apache webserver):
 

# a2dismod php5 …

# /etc/init.d/apache2 restart
…


To test the SuPHP is properly working on the Apache Webserver go into some of many hosted server websites DocumentRoot

And create new file called test_suphp.php with below content:

# vim test_suphp.php
<?php
system('id');
?>

Then open in browser http://whatever-website/test_suphp.php assuming that system(); function is not disabled for security reasons in php.ini you should get an User ID, GroupID bigger than reserved system IDs on GNU / Linux e.g. ID > UID / GID 99

Its also a good idea to take a look into SuPHP configuration file /etc/suphp/suphp.conf and tailor options according to your liking 

If different hosted client users home directories are into /home directory, set in suphp.conf

;Path all scripts have to be in

docroot=/home/


Also usually it is a good idea to set 

umask=0022 

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Check your Server Download / Upload Internet Speed from Console on Linux / BSD / Unix howto

Tuesday, March 17th, 2015

tux-check-internet-network-download-upload-speed-on-linux-console-terminal-linux-bsd-unix
If you've been given a new dedicated server from a New Dedicated-Server-Provider or VPS with Linux and you were told that a certain download speed to the Server is guaranteed from the server provider, in order to be sure the server's connection to the Internet told by service provider is correct it is useful to run a simple measurement console test after logging in remotely to the server via SSH.
Testing connection from Terminal is useful because as you probably know most of Linux / UNIX servers doesn't have a GUI interface and thus it is not possible to test Internet Up / Down Bandwidth through speedtest.net.
 

1. Testing Download Internet Speed given by ISP / Dedi-Server Provider from Linux Console

For the download speed (internet) test the historical approach was to just try downloading the Linux kernel source code from www.kernel.org with some text browser such as lynx or links count the seconds for which the download is completed and then multiple the kernel source archive size on the seconds to get an approximate bandwidth per second, however as nowdays internet connection speeds are much higher, thus it is better to try to download some Linux distribution iso file, you can still use kernel tar archive but it completed too fast to give you some good (adequate) statistics on Download bandwidth.

If its a fresh installed Linux server probably you will probably not have links / elinks and lynx text internet browers  installed so install them depending on deb / rpm distro with:

If on Deb Linuz distro:

 

root@pcfreak:/root# apt-get install –yes links elinks lynx
…

 

On RPM Based Linuz distro:
 

 

[root@fedora ~]# yum install -y lynx elinks links
…

 

Conduct Internet  Download Speed with links
root@pcfreak:/root# links https://www.kernel.org/pub/linux/kernel/v3.x/linux-3.19.1.tar.xz

check_your_download_speed-from-console-linux-with-links-text-browser

(Note that the kernel link is current latest stable Kernel source code archive in future that might change, so try with latest archive.)

You can also use non-interactive tool such as wget,  curl or lftp to measure internet download speed

To test Download Internet Speed with wget without saving anything to disk set output to go to /dev/null 

 

root@pcfreak:~# wget -O /dev/null https://www.pc-freak.net//~hipo/hirens-bootcd/HirensBootCD15/Hirens.BootCD.15.0.zip

 

check_bandwidth_download-internet-speed-with-wget-from-console-non-interactively-on-linux

You see the Download speed is 104 Mbit/s this is so because I'm conducting the download from my local 100Mbit network.

For the test you can use my mirrored version of Hirens BootCD

2. Testing Uplink Internet speed provided by ISP / Server Provider from Linux (SSH) Console

To test your uplink speed you will need lftp or iperf command tool.

 

root@pcfreak:~# apt-cache show lftp|grep -i descr -A 12
Description: Sophisticated command-line FTP/HTTP client programs
 Lftp is a file retrieving tool that supports FTP, HTTP, FISH, SFTP, HTTPS
 and FTPS protocols under both IPv4 and IPv6. Lftp has an amazing set of
 features, while preserving its interface as simple and easy as possible.
 .
 The main two advantages over other ftp clients are reliability and ability
 to perform tasks in background. It will reconnect and reget the file being
 transferred if the connection broke. You can start a transfer in background
 and continue browsing on the ftp site. It does this all in one process. When
 you have started background jobs and feel you are done, you can just exit
 lftp and it automatically moves to nohup mode and completes the transfers.
 It has also such nice features as reput and mirror. It can also download a
 file as soon as possible by using several connections at the same time.

 

root@pcfreak:/root# apt-cache show iperf|grep -i desc -A 2
Description: Internet Protocol bandwidth measuring tool
 Iperf is a modern alternative for measuring TCP and UDP bandwidth performance,
 allowing the tuning of various parameters and characteristics.

 

To test Upload Speed to Internet connect remotely and upload any FTP file:

 

root@pcfreak:/root# lftp -u hipo www.pc-freak.net -e 'put Hirens.BootCD.15.0.zip; bye'

 

uploading-file-with-lftp-screenshot-test-upload-internet-speed-linux

On Debian Linux to install iperf:

 

root@pcfreak:/root# apt-get install –yes iperf

 

On latest CentOS 7 and Fedora (and other RPM based) Linux, you will need to add RPMForge repository and install with yum

 

[root@centos ~]# rpm -ivh  rpmforge-release-0.5.3-1.el7.rf.x86_64.rpm
…
[root@centos ~]# yum -y install iperf
…

 

Once having iperf on the server the easiest way currently to test it is to use
serverius.net speedtest server –  located at the Serverius datacenters, AS50673 and is running on a 10GE connection with 5GB cap.

 

root@pcfreak:/root# iperf -c speedtest.serverius.net -P 10
————————————————————
Client connecting to speedtest.serverius.net, TCP port 5001
TCP window size: 16.0 KByte (default)
————————————————————
[ 12] local 83.228.93.76 port 54258 connected with 178.21.16.76 port 5001
[  7] local 83.228.93.76 port 54252 connected with 178.21.16.76 port 5001
[  5] local 83.228.93.76 port 54253 connected with 178.21.16.76 port 5001
[  9] local 83.228.93.76 port 54251 connected with 178.21.16.76 port 5001
[  3] local 83.228.93.76 port 54249 connected with 178.21.16.76 port 5001
[  4] local 83.228.93.76 port 54250 connected with 178.21.16.76 port 5001
[ 10] local 83.228.93.76 port 54254 connected with 178.21.16.76 port 5001
[ 11] local 83.228.93.76 port 54255 connected with 178.21.16.76 port 5001
[  6] local 83.228.93.76 port 54256 connected with 178.21.16.76 port 5001
[  8] local 83.228.93.76 port 54257 connected with 178.21.16.76 port 5001
[ ID] Interval       Transfer     Bandwidth
[  9]  0.0-10.2 sec  4.05 MBytes  3.33 Mbits/sec
[ 10]  0.0-10.2 sec  3.39 MBytes  2.78 Mbits/sec
[ 11]  0.0-10.3 sec  3.75 MBytes  3.06 Mbits/sec
[  4]  0.0-10.3 sec  3.43 MBytes  2.78 Mbits/sec
[ 12]  0.0-10.3 sec  3.92 MBytes  3.18 Mbits/sec
[  3]  0.0-10.4 sec  4.45 MBytes  3.58 Mbits/sec
[  5]  0.0-10.5 sec  4.06 MBytes  3.24 Mbits/sec
[  6]  0.0-10.5 sec  4.30 MBytes  3.42 Mbits/sec
[  8]  0.0-10.8 sec  3.92 MBytes  3.03 Mbits/sec
[  7]  0.0-10.9 sec  4.03 MBytes  3.11 Mbits/sec
[SUM]  0.0-10.9 sec  39.3 MBytes  30.3 Mbits/sec

 

You see currently my home machine has an Uplink of 30.3 Mbit/s per second, that's pretty nice since I've ordered a 100Mbits from my ISP (Unguaranteed Bandwidth Connection Speed) and as you might know it is a standard practice for many Internet Proviers to give Uplink speed of 1/4 from the ISP provided overall bandwidth 1/4 would be 25Mbi/s, meaning my ISP (Bergon.NET) is doing pretty well providing me with even more than promised (ordered) bandwidth.

Iperf is probably the choice of most sysadmins who have to do regular bandwidth in local networks speed between 2 servers or test  Internet Bandwidth speed on heterogenous network with Linux / BSDs / AIX / HP-UX (UNIXes). On HP-UX and AIX and other UNIXes for which iperf doesn't have port you have to compile it yourself.

If you don't have root /admin permissions on server and there is python language enterpreter installed you can use speedtest_cli.py script to test internet throughput connectivity
speedtest_cli uses speedtest.net to test server up / down link just in case if script is lost in future I've made ownload mirror of speedtest_cli.py is here

Quickest way to test net speed with speedtest_cli.py:

 

$ lynx -dump https://raw.github.com/sivel/speedtest-cli/master/speedtest_cli.py > speedtest_cli.py
$ chmod +x speedtest_cli.py
python speedtest_cli.py

speedtest_cli_pyhon_script_screenshot-on-gnu-linux-test-internet-network-speed-on-unix

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How to completely disable Replication in MySQL server 5.1.61 on Debian GNU / Linux

Monday, July 16th, 2012

Replication_mysql_disable

Some time ago on one of the Database MySQL servers, I've configured replication as it was required to test somethings. Eventually it turned out replication will be not used (for some reason) it was too slow and not fitting our company needs hence we needed to disable it.

It seemed logical to me that, simply removing any replication related directives from my.cnf and a restart of the SQL server will be enough to turn replication off on the Debian Linux host. Therefore I proceeded removed all replication configs from /etc/my/my.cnf and issued MySQL restart i. e.:

sql-server:~# /etc/init.d/mysql restart
....

This however didn't turned off replication,as I thought and in phpmyadminweb frontend interface, replication was still appearing to be active in the replication tab.

Something was still making the SQL server still act as an Replication Slave Host, so after a bit of pondering and trying to remember, the exact steps I took to make the replication work on the host I remembered that actually I issued:

mysql> START SLAVE;

Onwards I run:

mysql> SHOW SLAVE STATUS;
....

and found in the database the server was still running in Slave Replication mode

Hence to turn off the db host run as a Slave, I had to issue in mysql cli:

mysql> STOP SLAVE;
Query OK, 0 rows affected, 1 warning (0.01 sec)
mysql> RESET SLAVE;
Query OK, 0 rows affected, 1 warning (0.01 sec)

Then after a reload of SQL server in memory, the host finally stopped working as a Slave Replication host, e.g.

sql-server:~# /etc/init.d/mysql restart
....

After the restart, to re-assure myself the SQL server is no more set to run as MySQL replication Slave host:

mysql> SHOW SLAVE STATUS;
Empty set (0.00 sec)

Cheers 😉

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Posted in MySQL, System Administration | 1 Comment »

Create SSH Tunnel to MySQL server to access remote filtered MySQL port 3306 host through localhost port 3308

Friday, February 27th, 2015

create_ssh_tunnel_to-mysql_server-to-access-remote-filtered-mysql-on-port-3306-secure_ssh_traffic
On our Debian / CentOS / Ubuntu Linux and Windows servers we're running multiple MySQL servers and our customers sometimes need to access this servers.
This is usually problem because MySQL Db  servers are running in a DMZ Zone with a strong firewall and besides that for security reasons SQLs are configured to only listen for connections coming from localhost, I mean in config files across our Debian Linux servers and CentOS / RHEL Linux machines the /etc/mysql/my.cnf and /etc/my.cnf the setting for bind-address is 127.0.0.1:
 

[root@centos ~]# grep -i bind-address /etc/my.cnf 
bind-address            = 127.0.0.1
##bind-address  = 0.0.0.0


For source code developers which are accessing development SQL servers only through a VPN secured DMZ Network there are few MySQL servers witha allowed access remotely from all hosts, e.g. on those I have configured:
 

[root@ubuntu-dev ~]# grep -i bind-address /etc/my.cnf 

bind-address  = 0.0.0.0


However though clients insisted to have remote access to their MySQL Databases but since this is pretty unsecure, we decided not to configure MySQLs to listen to all available IP addresses / network interfaces. 
MySQl acess is allowed only through PhpMyAdmin accessible via Cleint's Web interface which on some servers is CPanel  and on other Kloxo (This is open source CPanel like very nice webhosting platform).

For some stubborn clients which wanted to have a mysql CLI and MySQL Desktop clients access to be able to easily analyze their databases with Desktop clients such as MySQL WorkBench there is a "hackers" like work around to create and use a MySQL Tunnel to SQL server from their local Windows PCs using standard OpenSSH Linux Client from Cygwin,  MobaXterm which already comes with the SSH client pre-installed and has easy GUI interface to create SSH tunnels or eventually use Putty's Plink (Command Line Interface) to create the tunnel

Anyways the preferred and recommended (easiest) way to achieve a tunnel between MySQL and local PC (nomatter whether Windows or Linux client system) is to use standard ssh client and below command:
 

ssh -o ServerAliveInterval=10 -M -T -M -N -L 3308:localhost:3306 your-server.your-domain.com


By default SSH tunnel will keep opened for 3 minutes and if not used it will automatically close to get around this issue, you might want to raise it to (lets say 15 minutes). To do so in home directory user has to add in:
 

~/.ssh/config

ServerAliveInterval 15
ServerAliveCountMax 4


Note that sometimes it is possible ven though ssh tunnel timeout value is raised to not take affect if there is some NAT (Network Adress Translation) with low timeout setting on a firewall level. If you face constant SSH Tunnel timeouts you can use below bash few lines code to auto-respawn SSH tunnel connection (for Windows users use MobaXterm or install in advance bash shell cygwin package):
 

while true
do
 ssh -o ServerAliveInterval=10 -M -T -M -N -L 3308:localhost:3306 your-server.your-domain.com
  sleep 15
done


Below is MySQLBench screenshot connected through server where this blog is located after establishing ssh tunnel to remote mysql server on port 3308 on localhost

mysql-workbench-database-analysis-and-management-gui-tool-convenient-for-data-migratin-and-queries-screenshot-

There is also another alternative way to access remote firewall filtered mysql servers without running complex commands to Run a tunnel which we recommend for clients (sql developers / sql designers) by using HeidiSQL (which is a useful tool for webdevelopers who has to deal with MySQL and MSSQL hosted Dbs).

heidisql-show-host_processlist-screenshot

To connect to remote MySQL server through a Tunnel using Heidi:

mysql_connection_configuration-heidi-mysql-gui-connect-tool

 

In the ‘Settings’ tab

1. In the dropdown list of ‘Network type’, please select SSH tunnel

2. Hostname/IP: localhost (even you are connecting remotely)

3. Username & Password: your mysql user and password

Next, in the tab SSH Tunnel:

1. specify plink.exe or you need to download it and specify where it’s located

2. Host + port: the remote IP of your SSH server(should be MySQL server as well), port 22 if you don’t change anything

3. Username & password: SSH username (not MySQL user)

 

heidi-connection_ssh_tunnel_configuration-heidi-sql-tool-screenshot
 

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Recover/Restore unbootable GRUB boot loader on Debian Testing GNU/Linux using Linux LiveCD (Debian Install CD1)

Tuesday, July 6th, 2010

I’ve recently broke my grub untentianally while whiping out one of my disk partitions who was prepared to run a hackintosh.
Thus yesterday while switching on my notebook I was unpleasently surprised with an error Grub Error 17 and the boot process was hanging before it would even get to grub’s OS select menu.

That was nasty and gave me a big headache, since I wasn’t even sure if my partitions are still present.
What made things even worse that I haven’t created any backups preliminary to prepare for an emergency!
Thus restoring my system was absolutely compulsory at any cost.
In recovering the my grub boot manager I have used as a basis of my recovery an article called How to install Grub from a live Ubuntu cd
Though the article is quite comprehensive, it’s written a bit foolish, probably because it targets Ubuntu novice users 🙂
Another interesting article that gave me a hand during solving my issues was HOWTO: install grub with a chroot
Anyways, My first unsuccessful attempt was following a mix of the aforementioned articles and desperately trying to chroot to my mounted unbootable partition in order to be able to rewrite the grub loader in my MBR.
The error that slap me in my face during chroot was:

chroot: cannot execute /bin/sh : exec format error

Ghh Terrible … After reasoning on the shitty error I came to the conclusion that probably the livecd I’m trying to chroot to my debian linux partition is probably using a different incompatible version of glibc , if that kind of logic is true I concluded that it’s most likely that the glibc on my Linux system is newer (I came to that assumption because I was booting from livecds (Elive, Live CentOS as well Sabayon Linux, which were burnt about two years ago).

To proof my guesses I decided to try using Debian testing Squeeze/Sid install cd . That is the time to mention that I’m running Debian testing/unstable under the code name (Squeeze / Sid).
I downloaded the Debian testing amd64 last built image from here burnt it to a cd on another pc.
And booted it to my notebook, I wasn’t completely sure if the Install CD would have all the necessary recovery tools that I would need to rebuilt my grub but eventually it happened that the debian install cd1 has everything necessary for emergency situations like this one.

After I booted from the newly burned Debian install cd I followed the following recovery route to be able to recovery my system back to normal.It took me a while until I come with the steps described here, but I won’t get into details for brevity

1. Make new dir where you intend to mount your Linux partition and mount /proc, /dev, /dev/pts filesystems and the partition itself

noah:~# mkdir /mnt/root
noah:~# mount -t ext3 /dev/sda8 /mnt/root
noah:~# mount -o bind /dev /mnt/root/dev
noah:~# mount devpts /dev/pts -t devpts

Change /dev/sda8 in the above example commands with your partition name and number.
2. chroot to the mounted partition in order to be able to use your filesystem, exactly like you normally use it when you’re using your Linux partition

noah:~# chroot /mnt/root /bin/bash

Hopefully now you should be in locked in your filesystem and use your Linux non-bootable system as usual.

Being able to access your /boot/grub directory I suggest you first check that everything inside:

/boot/grub/menu.lst is well defined and there are no problems with the paths to the Linux partitions.

Next issue the following commands which will hopefully recover your broken grub boot loader.

noah:~# grub
noah:~# find /boot/grub/stage1

The second command find /boot/grub/stage1 should provide you with your partitions range e.g. it should return something like:

root (hd0,7)

Nevertheless in my case instead of the expected root (hd0,7) , I was returned

/boot/grub/stage1 not found

Useless to say this is uncool 🙂

As a normal reaction I tried experimenting in order to fix the mess. Logically enough I tried to reinstall grub using the

noah:~# grub-install --root-directory=/boot /dev/sda
noah:~# update-grub

To check if that would fix my grub issues I restarted my notebook. Well now grub menu appeared with some error generated by splashy
Trying to boot any of the setup Linux kernels was failing with some kind of error where the root file system was trying to be loaded from /root directory instead of the normal / because of that neither /proc /dev and /sys filesystems was unable to be mounted and the boot process was interrupting in some kind of rescue mode similar to busybox, though it was a was less flexible than a normal busybox shell.

To solve that shitty issue I once again booted with the Debian Testing (Sid / Squeeze ) Install CD1 and used the commands displayed above to mount my linux partition.

Next I reinstalled the following packages:

noah:~# apt-get update
noah:~# apt-get install --reinstall linux-image-amd64 uswsusp hibernate grub grub-common initramfs-tools

Here the grub reinstall actually required me to install the new grub generation 2 (version 2)
It was also necessary to remove the splashy

noah:~# apt-get remove splashy
As well as to grep through all my /etc/ and look for a /dev/sda6 and substitute it with my changed partition name /dev/sda8

One major thing where I substituted /dev/sda6 to my actual linux partition now with a name /dev/sda8 was in:

initramfs-tools/conf.d/resumeThe kernel reinstall and consequently (update) does offered me to substitute my normal /dev/sda* content in my /etc/fstab to some UUIDS like UUID=ba6058da-37f8-4065-854b-e3d0a874fb4e

Including this UUIDs and restarting now rendered my system completely unbootable … So I booted once again from the debian install cd .. arrgh 🙂 and removed the UUID new included lines in /etc/fstab and left the good old declarations.
After rebooting the system now my system booted once again! Hooray! All my data and everything is completely intact now Thanks God! 🙂

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Posted in Linux, Linux and FreeBSD Desktop, System Administration | 8 Comments »

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