Loadbalancer Musings

So recently I have been thinking about getting a load balancer/service, but worried about it being a single point of failure, as well as a hefty price. So how about a setup where we have multiple frontend webservers which are all setup to be a load balancer for each other?

Something like the following would be configured in DNS:

This would round robin the requests to any of the available frontend web servers.

In the Nginx configuration for each we would then load balance as well (including itself), this would automatically detect if a web server was unavailable and try another:

When I tested this with some VM’s it has worked flawlessly. Any thoughts or further improvements that could be made?

Vagrant

logo_vagrant

I’ve been using Vagrant as part of my development process for about 6-8 months now. It makes it so much easier – I’m not too sure how I managed before!

I now include a Vagrantfile (it’s config) with every project/repo that I build.
Using this I can launch a box with a specific hardware/software configuration depending on the projects requirement.

I have a number of boxes which I’ve manually built and are hosted online. If I decide to make an update (upgrade php or mysql for example) the next time the local box is started it will automatically update from the hosted box. Neat huh?

Check out my Github repo for my debian web box: https://github.com/louisnorthmore/vagrant-debian-web

So what’s next? Well… coupled with Ansible I should be able to nail down my deployment process & remote server management for good.

Fix scrolling on Synergy clients

Synergy

I have a number of systems & monitors on my desk, and one thing which has irked me for long time is scrolling didn’t work on one of my linux synergy clients. Today I needed to fix it!

With a little bit of help from here: https://code.google.com/p/synergy-plus/issues/detail?id=28#c17 it was fixed within minutes!

First off all quit synergyc, quicksynergy or whatever you are using.
Lets now start it manually, fire up a terminal and enter:

$ synergyc -f -d WARNING --name debian 192.168.0.200

Synergy should now be working as normal, now open up a web browser and attempt to scroll.

You should see messages similar to the following:

Feb 1 18:32:45 localhost Synergy+ 1.3.4: 2010-02-01T18:32:45 WARNING: Wheel scroll
delta (28) smaller than threshold (120)#012#011CXWindowsScreen.cpp,858

That delta number is the important bit!

Quit synergyc and now add --yscroll 28 (or whatever your delta is) the full command should look like this:

$ synergyc -f -d WARNING --yscroll 28 --name debian 192.168.0.200

Scrolling should now work!

If this works for you (or doesn’t!) let me know in the comments!