How to edit/Modify/Delete Bookmarks in vinagre?

Vinagre bookmarks are stored in the file vinagre-bookmarks.xml file under /home//.local/share/vinagre directory.

As all the bookmarks are stored in single line be bit more cautious before editing, otherwise you will endup mess.
(I Recommend to keep a backup of the file before editing)

All the bookmarks are starts and ends with & xml node.  So as per your wish do edit/modify the Bookmarks.

Example entry in vinagre-bookmarks.xml file: <item><item><protocol>vnc</protocol><name>Asset-Mgmt-Client-1</name> <host>10.184.48.82</host><username></username><port>5915</port> <fullscreen>0</fullscreen><width>800</width><height>600</height> <view_only>0</view_only><scaling>0</scaling><keep_ratio>1</keep_ratio> <depth_profile>0</depth_profile><lossy_encoding>0</lossy_encoding></item>

How to fix/suppress "apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1." warning message?

Warning message Before the fix:

"apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message"


Fix: 
execute the following command in terminal

echo "ServerName localhost" | sudo tee -a /etc/apache2/apache2.conf

Now restart apache server by executing the following command

sudo /etc/init.d/apache2 restart


Message after the fix:
[ ok ] Restarting web server: apache2.

How to resolve "no suitable module for running kernel found" error in virtualbox instalation in debian linux?

1. Check wheather you machine is installed with "linux-headers-, linux-image-"
by issueing the follwing command in terminal.

  $dpkg -l | grep linux

In my case my kernel version is "3.16.0-4-686-pae" so the output of the above command would be something like as follows, 

Missing linux headers package

If you don't find any linux-headers or linux-images then you must install them first.

2. To find the your kernel version use the following command
  $uname -a

[ My output -> Linux hostname 3.16.0-4-686-pae #1 SMP Debian 3.16.36-1+deb8u2 (2016-10-19) i686 GNU/Linux ]

now install the required packages specified in step 1.

3.  Uninstall your previous virutalbox package and reinstall it.

  $sudo apt-get remove --purge virtualbox
  $sudo apt-get instlal virtualbox

4.  Restart you machine.

How to find filesystem type in linux machine?

There are many ways to find the filesystem of a partition in linux (provided the partition mounted)
Following are the command line tools run these commands as is in terminal.

1.  cat /etc/fstab

2.  cat /etc/mtab

3.  mount

4.  df -T

Note:  You should know the partition number (like /dev/sda2, /dev/sda4 etc.,) or the partition label (Like mypendrive, 8GB_drive etc.,) or the UUID number.

Youtube videos not working asking for flash plugin | How to install adobe-flash player in (Debian based)Linux?

1.  Download the adobe-flash player from -> https://get.adobe.com/flashplayer/

2.  Select ".tar.gz for other linux" then click on "Download now"
        Note:  If you are using debian or rpm based linux then select your option accordingly.

3.  Unpack the download file (Right-click on the file and select -> "Extract here")
        (Note:  There will be a readme.txt file inside the extracted directory (like install_flash_player_11_linux.i386).  This file contains the detailed instructions for installation for all the flavours of Linux.)

4.  copy the "libflashplayer.so" file into following directories

        a. /usr/lib/flashplugin-nonfree/
        b. /usr/lib/mozilla/plugins/
        If you have chromium browser then copy the file into
        c. /usr/lib/chromium/plugins/
       
5.    Test the flash plugin -> Close the browsers (if already opened) then start again.
        Now, open youtube and check the videos will play like charm.