Some time ago I built a setup using Amazon’s S3 and Cloudfront that would allow large file uploads/downloads directly from the an S3 bucket, through a Cloudfront endpoint (which provided both a lower latency and allowed using SSL on a … Continue reading
Category Archives: Systems Admin
WebSockets – Varnish, Nginx, and Node.js
Like many others I have been drawn in by the appeal of websockets and their use in (near) real-time communication. As such one of my current projects uses Node.js and websockets (via socket.io). To maximize compatibility, I would, of course, … Continue reading
DRBD on Amazon’s Linux
Note: this was done more as an experiment than for something I intended to use in production – so consider it to be more a compilation of notes than a full out procedure. DRBD – Distributed Replicated Block Device – … Continue reading
Varnish – Nothing but 503s
I use Varnish on my production server without any issues – it works quite well, and I have come to consider it an essential component in my server stack. I have recently been having a bit of trouble with a … Continue reading
Root Autologin on CentOS
Do not do this – it is a very, very bad idea!!! Doing this for any reason (other than the fun of it – in a ‘safe’ virtual environment) should carry with it an eternal ban prohibiting the use of … Continue reading
Windowless VirtualBox VMs (Windows Host)
Since I haven’t gotten around to playing with VMware or xen yet – VirtualBox is what I am using for virtualization in my test environment. Under Windows I like to use PuTTy to connect to my VMs – even those … Continue reading
Directly connecting to PHP-FPM
When it comes to troubleshooting, it is ideal to be able to isolate each component of a system. In the case where multiple connected items are performing correctly, they can sometimes be grouped together – however, if one of these … Continue reading
Autoscaling with custom metrics
One of the appeals of cloud computing is the idea of using what you need when you need. One of the ways that Amazon provides for this is through autoscaling. In essence, this allows you to vary the number of … Continue reading
WordPress – SSL login page without SSL admin
In WordPress (v3.3), FORCE_SSL_LOGIN will transmit login credentials over SSL, however, the login page itself may be accessed over HTTP (as opposed to HTTPS). If the login page is accessed via HTTP, the user has no (easy) way of verifying … Continue reading
Installing Corosync on EC2
The notes for this have been sitting on my computer for almost 6 months, but a comment from today spurred me onto editing, updating, and posting them. Corosync is a messaging layer used for high-availability. It serves essentially the same … Continue reading
Adding Swap Space to an EC2 Instance
The t1.micro instance comes with only 602MB of memory. Especially under high load, it is quite easy to deplete the available memory – and since no swap space is enabled by default, this can quickly lead to a server becoming … Continue reading
Shrink EBS Root
My EC2 instances are setup to have only the operating system and program files on the root volume, with all other data (logs, mail, etc.) on a second EBS volume. This leads to a very stable root volume, which sees … Continue reading
Installing ApacheBench without Apache on Amazon’s Linux
Having recently switched to a setup with only nginx (and no apache), I found myself wanting to run some tests. As nice as siege is, I rather like ApacheBench (ab). However, I really didn’t want to install all of Apache … Continue reading
Connect to Amazon’s Linux via WinSCP as root
SCP offers a number of advantages over FTP, not the least of which include no setup (you don’t need an FTP server) and increased security. However, when setting up a server, it can be rather inconvenient to be unable to … Continue reading