Mysql workbench working with key based exchange mechanisms

It appears newer linux sshd configs (fedora 22) by default include a smaller set of key exchange based mechanisms that they have turned on.

This means that it gives errors saying it is unable to connect to the server. To fix this you need to enable some of the older key exchange mechanisms,

Adding this line to /etc/ssh/sshd_config and restarting the sshd server will fix it

KexAlgorithms curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1

Credits to: http://serverfault.com/questions/692060/mysql-workbench-with-debian-jessie-tcp-ip-over-ssh-does-not-work

Install Virtualbox guest additions on Fedora 21 XFCE

Installing via the normal route didn’t work and meant I couldn’t easily resize the screen. Doing the below allowed me to use the resize easily.

  1. Install rpmfusion on fedora
  2. run `sudo yum install akmod-VirtualBox VirtualBox-guest`
  3. run `cd /usr/src/akmods`
  4. run `sudo rpm -ivh VirtualBox-*.rpm`

Once this was installed, rebooting will give you access to shared folders and fullscreen mode

Found the fix on the fedora forums for fedora 19

Using Nvidia Optimus on Fedora

If your computer is recent and has an i3/i5/i7 intel core and a Nvidia graphics card it likely uses Optimus technology. This smart piece of software turns off the power-hungry Nvidia graphics card and runs most programs on the integrated intel graphics chip. In laptops this can save a lot of power. However this solution is only available in windows 7 upwards.

The problem occurs when you are using an operating system that doesn’t support this, as in most cases both cards will run all the time, causing major battery drain. On laptops this can severely shorten the battery life.

However there is a solution to this called bumblebee. This piece of software aims to offer similar technology in Linux-based machines. I found many tutorials on how to install it and work and ended up reinstalling fedora (17 at the time) several times.

However, I found a post from the NC State University Technical Staff Exchange on how to install bumblebee for Fedora and Redhat based distributions. I used this before to install on Fedora 17 and now just today on Fedora 18. Previously I was having a lot of issues getting it to work on Fedora 18 and according to them “nouveau drivers do not work on fedora 18 at this time” which after following their guide and installing the Nvidia ones it started to work.

If you are running a laptop with a new intel core and Nvidia graphics card and are getting poor battery life, I suggest you looking into seeing if you have Optimus technology in your laptop, and if so try this.

However, there is a warning, you will be messing around with your display drivers which could cause your system to not be able to display any GUI. Back up everything before trying this.

As usual, if you have any questions, it worked for you or you have something to add to my post, leave a comment!

Tile windows like Windows 7 on XFCE

Windows 7 has a really nice feature that lets you tile a window to the left or right of the screen, allowing easier placement. This is normally activated with the Windows-(left, right, up down) Arrow key combination.

I had searched how to do this with XFCE for a while and today after upgrading to Fedora 18, XFCE 4.2 i found it.

If you go to Settings -> Window Manager -> Keyboard

There is a list of keyboard shortcuts, there is 4 towards the bottom called “Tile window to the (left, right, top, bottom)”. This is exactly what i wanted and have now assigned Windows-Left Arrow key and the other combinations to use this.

It’s a small thing, but makes resizing and moving windows around a lot quicker than manually doing it.

XFCE Application Menu Icons Missing

After i installed Fedora 18 XFCE i found that it by default doesnt show the icons on the application menu.

I normally navigate it by checking the images and not reading the words, so this inconvenienced me. On checking the properties I found that “Show icons in menu” was checked but it did not seem to work.

However a solution was suggested, and after running it and logging out and in, it worked.

Run this, then restart (or maybe just logout) and it should be fixed next time you login

gconftool-2 --type boolean --set /desktop/gnome/interface/buttons_have_icons true
gconftool-2 --type boolean --set /desktop/gnome/interface/menus_have_icons true

Leave a comment stating your linux distribution and setup if it worked or ask for any help in the comments.