Home networks with NAS units are great for local storage of files, but I have always wary of exposing these servers directly to the great unwashed of the WWW as, quite frankly people, you sometimes get up to mischief.
YOU CAN SECURE THESE YOU KNOW
True. And I used to run a NAS ( +NETGEAR ReadyNAS ) from my home router, exposed to the internet, protected by SSH keys and obscure port mappings (YAY). Having not built the NAS linux kernel and user space from scratch however (or fully characterized all the processes / apps running on it), there was always a niggling doubt that it was simply obscure, not secure. Also, it consumed much of my time to maintain and one day, the device killed one of the RAID disks – the writing was on the wall for this little box that could, but did not. So I reinstalled the original firmware and for the sake of my kids baby photos, turning it back into an basic NAS box.
WHAT DO YOU WANT FROM THIS CLOUD ANYWAY? YOU BRITS ALWAYS COMPLAIN ABOUT THE RAIN
Well, I had a bunch of things I was messing around with, all of which needed something to talk to that was “always on”. A box in the cloud was perfect for this, so I started looking around to see what was available. Turns out there are a couple of ways to ways to get one of these there cloud boxes that fitted my "pay nothing to anyone" budget.
- A dedicated PC or MAC, kept in a data center of your choosing
- You can supply the HW and pay the hosting centre fees or rent one
- The hosting service provides power, a network connection and a fixed IP address
- Runs your OS of choice! AmigaOS please.
- Physical access is generally required if you provided the box yourself, or some funky BIOS SW is available on pro servers to enable remote administration – some even support KVM and the ability to supply an ISO image for the CD or USB drives over the net.
- A Virtual Private Server (VPS)
- You pay a hosting service for an timeshare on a super fast server
- Share CPU, memory, storage and network with multiple users
- The hosting service can run a large selection of virtual machines / OS's for you to use, but the list is limited to what sells in volume (no AmigaOS…)
The latter sounded good, but VPS seems to come in many shapes and sizes! The characteristics I was looking for were limited to:
- "Hack it if you want, its quick to reinstall and there is nothing secret on there anyway” administration panel access
- Low(ish) processing and local storage
- Good enough bandwidth limits (no plans to host torrents on it)
- Super cheap!
THE LOW END BOX
The site LowEndBox was a great read on the different solutions available in the VPS Linux box hosting arena. Much discussion basically boils down to the following however:
- Price
- Reliability (up time)
- Where is the server located
- Are there any deals?
- Does the owner post on the forums and does he reply to crazies posting about his company?
Any caveats? Well, the VPS is listed as "unmanaged", meaning that outside of the initial install, its all down to you to configure.
Update: Further investigations shows lowendstock as also being a great resource for budget VPS solutions. At the time of writing "FOUR DOLLAR VPS".
URPAD
12 dollar dollar bill yo’s later, and we’re in. What I liked:
- Super quick to setup - payment went through and I received my login almost immediately
- Easy to access hosting controls to wipe / provision the server
- Small but good selection of Ubuntu packages pre-installed and APT running quickly to install any missing items
- Reliable hosting (never found it broken or down so far)
The only negative would be that at one time, I found the VPS going super slow for a few minutes when I was simply at the shell – nothing else running. It wasn't anything critical, but it led to a wander into the tech behind their virtual server stack.
OpenVZ vs VMware
URPad runs OpenVZ. According to its wiki, its containerization of an OS instead of a entire virtual machine emulator (such as VMWare or VirtualBox). The interwebs do a better job of “what” here, so I knocked up a quick table of some of the differences in relation to the “why did my server go slow!” witch hunt:
| Virtualization | Containerization | |
| Single Kernel? | No | Yes |
| Full System Isolation | Yes | No (common kernel) |
| Performance | OK | Better |
| Scheduler Contention | Yes | Yes |
| Resource control | Per VM | Per user within the VM |
| Isolation | Complete | Partial |
How could this explain the slow down? Whilst a virtualized OS is still at the whim of the host’s scheduler (memory allocation, disk access etc…), within the virtualized OS, everything runs 'evenly'(ish) within that virtual guest. In theory, you can lock down the scheduling time of the virtual machines to a fairly granular level. With the containerized VM, as the kernel is not emulated, its possible to call various syscalls, sufficiently enough to load up the entire system and monopolize the hosts CPU time.
The pricing of VPS solutions based on containerization is fairly obvious – cheaper maintenance / resource requirements per virtual host and I am happy with the tradeoffs. Would I want a production server running on this infrastructure however? Probably not. In fact, I’d be straight over to Amazon .
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