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Showing posts from November, 2014

wget and Install Oracle JDK 8 on VPS

wget --no-check-certificate --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u25-b17/jdk-8u25-linux-x64.tar.gz

Quorum Service Failure Tolerance

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For zero-downtime rolling-updates, services need to maintain a quorum while nodes are being added and removed. When a  node is added, the total member count and quorum size must be increased to avoid a potential split brain upon a network partitioning scenario if a failure or extended delay were to occur during a rolling upgrade. A complex service with many nodes may be continuously in a state of rolling-updates to upgraded OS or foundation software, add security patches, or deploy application bug fixes or new features.

Assume we want a service to always be able to tolerate two node failures before halting for reliability/availability. From the table below, the minimum is 5 initial member nodes. With less than 5 nodes two node failures cause service updates to halt in order to guarantee consistency. 

When performing a rolling update a new node is added. When the new node is synchronized and brought into the quorum, the total member node count increases by one. This increases the node fa…

Ubuntu gnome classic Add to launcher, menu, toolbar

I prefer the gnome classic interface for easy of use and productivity. I like the tiny launcher bar and utilities on the top and the tiny open apps bar on the bottom.

Unfortunately adding back the gnome classic isn't the same as the original. Can't just right click to add new launchers anymore.

Super(Window Key) + Alt + Mouse Right Click

I can't stand the current Ubuntu Unity interface. Apparently I'm odd thinking that a windows menus don't belong divorced from the window itself. Yes, I can't stand the OSX interface either - if OSX supported highlight to copy and middle click to paste on more than just terminal window I might be a bit more tolerant.



Rearrange launcher icons with:

Alt + Mouse Middle click and drag


Remove launcher icon with:

    Super(Window Key) + Alt + Mouse Right Click then Remove From Panel

Mount remote filesystem via ssh: sshfs

Ubuntu doc

Install sshfs
sudo apt-get install sshfs

Add user to fuse group
sudo adduser troy fuse

Update config
to allow other users to access remotely mounted directory
sudo gedit /etc/fuse.conf
uncomment allow_other

Create mount point:
sudo mkdir /media/troy/test1

Mount
sudo sshfs -o allow_other -o ServerAliveInterval=120 troy@111.222.33.123:/home/troy /media/troy/test1/

UnMount
sudo umount /media/troy/test1/

following did not work

sudo fusermount -u /media/troy/test1

fusermount: entry for /media/troy/test1 not found in /etc/mtab