How to choose a good OpenSim host

Update: Full, up-to-date list of OpenSim hosting providers is here.

Running an OpenSimulator instance is a challenging prospect for many — there are a number of important criteria you should be looking at before purchasing, but the single most important question is: “Will I be managing this myself?”

“Do it yourself”

DIY Hosting OpenSim while relatively easy by comparison to most hosting software, is still not something that should be done by the technically uninitiated. OpenSim requires a healthy amount of maintainence in the form of updates, backups and patching.

Virtual or Dedicated?

For DIY hosting you have two choices in terms of hosting – Virtual Private Servers (VPS) or Dedicated Servers. Virtual Servers are a percentage of a physical server provided inside of a virtual machine. Virtual servers are often significantly cheaper than a dedicated server, however come at a heavy cost in performance.

Virtual server pricing starts at approximately US$15.00 per month. Dedicated servers will start at approximately US$50.00 per month. Virtual servers are appropriate for low performance private sandboxes, Dedicated servers are a must for public or regular usage.

A final note on dedicated servers – the most inexpensive dedicated server will often outperform the most expensive VPS. If you are on the price border between the two, I recommend switching to the lower performance, but dedicated server – than the higher performance but shared VPS.

Linux or Windows?

Unless you have significant investments in using Linux for your hosting, I recommend using Windows 2003 or 2008, especially if you are not familiar with running hosting environments. The reasons for this are fairly simple – Mono has memory management problems, memory requirements under Mono are often doubled or quadrupled.

Unfortunately Windows server is not always availible – especially at the lower price ranges. Microsoft charges hosting companies a $10/month per cpu fee for Windows Server, so this will always be passed on in the form of higher prices. In the highly competitive VPS industry this price increase makes good Windows VPSs a rare niche.

What processor?

OpenSim will very rarely peg your processor – I would not bother investing too much into the processing capacity of your instance or server. (Whether a VPS or Dedicated machine).

My own experience says that “off the shelf” desktop processors are more than adequate. Here at DeepThink we have standardised on Xeon 3220 based machines (Quad Core, 2.4Ghz) and we find these are more than suitable for our higher-end clients. For an average user, a off-the-shelf Core2Duo is more than sufficient.

How much memory?

This is a much more relevant question for OpenSim. If you are running on Mono, I recommend no less than 1GB of memory per region (512MB if it is mostly empty). If you are running Windows/.NET you can use a rule of thumb at approximately 384 to 512mb per region.

A more precise metric is to total up the following: A base cost of 200mb, total size of all textures in the region + 30% in megabytes (average region is around 50mb), 30mb per 1,000 primitives, 50mb per concurrent user and double the sum if you are running under Mono.

So a region with 5,000 primitives, an average number of textures (50mb) and ten concurrent users you should allocate approximately 900MB of memory for .NET and 1.8GB for Mono. Leave at least 100mb on top of this sum for the operating system itself; if the machine runs out of memory page file access will cripple the performance of your region.

Memory should be as fast as possible – the faster you can get the better.

How much hard disk?

None. OpenSim rarely uses more than a few gigabytes of space unless you are operating a large grid ( is only about 120GB of assets currently). Anything over 10GB is sufficient.

How much bandwidth?

This is a slightly tougher question to answer – it depends a lot on your sim, the complexity and texture detail, the number of visitors. We at DeepThink sponsor the servers running the Plaza’s, which I believe are the six most visited OpenSim instances running. The Plazas are broken up over two physical machines – each uses about 240GB of bandwidth each month – or approximately 80GB per region per month.

In pratice your region should come in significantly under this – but I recommend making sure you have at least 100GB of traffic per region in the event that you create a popular space. Most hosts provide at least 1TB of transfer on dedicated servers, so this should in most cases be a non-concern.

The other side of bandwidth is connectivity – how fast your server can speak with the outside world. I recommend having at least 200kbit per concurrent user. So for a standard ‘10 concurrent’ situation, you should have at least 2mbit of connectivity.

Backup Space

Make sure to have some kind of external backup system – most hosting providers will sell you SFTP access to a backup server, however make sure that they in turn provide good backup policies on your backups (offsite backup, etc.). OpenSim can be very fickle software, so make sure you have a good backup routine setup.


If you are a non-american user or cater to a foreign crowd, Latency is a very important issue. Latency is the “lag” between when you do an action and when it occurs on the simulation server – unfortunately latency is often best fixed by changing the geographical location of your servers.

If you cater to an audience in a specific country – I would recommend searching for servers in countries nearby. Often localised hosting is several times more expensive than in the US due to higher prices for local bandwidth, however most of the time there is a cheaper alternative nearby. For example, Japan has very high local server costs – but Korean or Singaporean servers are cheaper and have similar latency characteristics.



Dedicated Servers

CariNet (San Diego, CA, USA)

CariNet have been a popular choice for people running regions on OSGrid thanks to great pricing and astonishgly quick setup times. Their live support is pretty good and tends to fix most issues within 30 minutes of reporting. Cari have a highly flexible pricing system – so make sure to remember to include additional RAM and the Windows operating system with your purchases.

CariNet are also an official sponsor of, providing regular free upgrades to the official servers that are hosted there (Currently the two plaza machines and the one welcome machine). They have also provided some special pricing for OpenSim users – see the italics below.

Pricing: Minimum $50.00 per month (special offer at time of writing).

I spoke with CariNet’s sales department, and we have worked out a few “OpenSim Optimized” configurations –

  • High Performance – Windows, 4 Core Xeon, 4GB configuration is US$200.00/mo with no setup fee.
    This configuration is ideal for a “SL-replacement” style region host, you could probably get a couple of regions off this hardware, but the exact number will vary as above. I would estimate approximately 2 “Full Regions” could be run on this hardware configuration.
    If you want this server for only $160/month (but with a $120 setup), contact sales via their Live Chat with the discount code “OSGRID”. (Speak with Mike or Shawn)
  • Mid-Range – Windows, Core2Duo, 2GB configuration is US$140/mo with no setup fee.
    Expect to get one heavy region out of this configuration (or quite a few “homestead-esque” regions) – as always, this varies based on consumption.
    As above, if you want this server for only $120/month (but with a $60 setup), contact sales via their Live Chat with the discount code “OSGRID”. (Speak with Mike or Shawn)
  • Low-End – Windows, Celeron 2 Core, 2GB configuration is US$125/mo with no setup fee
    Consider this a homestead replacement, you should be able to get a small number of “homestead-equivilents” running off of this – obviously you dont have primitive limits or things like that, but you will notice degrading performance if you rely on a lot of scripted functionality.
    As above, if you want this server for only $105/month (but with a $60 setup), contact sales via their Live Chat with the discount code “OSGRID”. (Speak with Mike or Shawn)

Annual and quarterly discounts are availible for paying more than one month at a time.


OVH (Paris, France, EU)

OVH are the largest dedicated server host in Europe and provide unbeatable pricing on European servers. English pricing is expensive, however the same servers ordered from their French or German language sites are 10-20% cheaper.

OVH provide large amounts of memory and disk space by default, so very little customisation is required on their default servers. Windows 2003/2008 is an additional EUR 15.00 per month. Their RPS low-end machines may be a suitable mid-way point between a VPS and a full machine, but I haven’t tested one myself.

Pricing: Minimum EUR 49.95 per month. An OpenSim optimized configuration will start at EUR 114.00 per month (fully equipped).


Virtual Servers

Tektonic (Dallas, TX, USA)

Highly recommended by one of our employees, Tektonic provide good quality Linux VPS solutions – while they only offer Linux based VPS instances, their pricing is affordable and do not appear to oversell their servers in any noticable capacity.

Pricing: Minimum $15.00 per month. A “workshop” quality VPS is US$28.00 per month.


Slicehost (St Louis, MO, USA)

Slicehost guaruntee a minimum level of performance on their virtual servers which makes them more expensive than other hosts, however have a solid customer service reputation and a high quality control panel.

Pricing: Minimum $20.00 per month. A “workshop” quality VPS is US$38.00 per month.


FsckVPS (Atlanta, LA or Texas)

FsckVPS is often recommend on the OSGrid forums as a potential host – their slices are of a reasonable configuration and have plenty of memory availible. Processing time is more limited and some users have complained about running into processor limits, so their higher end packages are recommended.

Pricing: Minimum $9.95 per month. A “workshop” quality VPS is $19.90 per month, however I recommend the $34.90 plan if you plan on concurrent users.


“Someone host it for me”

As an alternative to setting up and managing your own OpenSim instance, you can pay for someone else to manage it for you. Often this is simply bundled with a grid – however a number of companies (including DeepThink) offer managed hosting services for OpenSim.

On average, an OpenSim instance will take around four hours of maintanence each month – at an average industry salary this is around $80.00 per month to the hosting company in engineering costs. You should expect the margin per-server to be about this size.

OpenSim hosting companies will charge based on one of two methods – the first method is Second Life(r) style limits – Primitive, Avatar and Script limitations. The companies that charge this way are generally those providing regions within a grid.

The second method is charging for the underlying service used – Processor time, RAM usage and Bandwidth. The companies offering this tend to be fairly agnostic as to where your regions will connect.

An important distinction between the two methods is that you will often get more ‘bang for buck’ on the underlying capacity. For instance if you need multiple low performance regions – you will come out significantly ahead by purchasing server time rather than regions. Likewise if you need a single high performance region you can tailor your requirements more specifically.

A final note – many simulators are sold as ’supporting 45,000 prims’. This is not reflective of actual usage – the 45,000 number is the largest number the Second Life(R) client will display, however on the backend there is often no limit. That however does not mean the region is capable of supporting 45,000 prims.

We often find that simulator performance degrades rapidly past the 10,000 primitive limit per region and it requires a significant amount of work to get more than 15,000 prims into a region while the region itself is stable, especially when scripts and multiple users are factored into the equasion.

As an addendum to the above – the per region count is not reflective of the per-simulator count. OpenSim can host multiple regions per simulator instance and we have found that the simulator instance itself can host in excess of 100,000 primitives as long as they are distributed between multiple regions.

A note on SLAs and Uptime

OpenSim is still alpha software. If you expect 99%+ uptime, you will also expect to pay for it. Keeping a region running with guarunteed uptime requires active maintainence and attention by an engineer. This means it is impactical to expect 99%+ uptime unless you can afford a technician 24/7.

Our experience with client projects is between 97.6% and 99.2% uptime over the course of a month. (including scheduled and unscheduled maintainence) – this will vary slightly depending on the version of OpenSim used, number of users and other factors.

If someone claims to offer bug-free and stable deployments of OpenSim, they are probably lying or are very naieve. OpenSim will occasionally run into bugs. If you have a specific project in mind that requires a production deployment it is strongly recommended to hire a consultant who is familiar with the OpenSim project (eg DeepThink, IBM, 3Di, Tribal Media, etc.).

List of companies providing OpenSim hosting (note this is incomplete – there are likely to be others)

Customized OpenSim Hosting Providers

The following companies provide customisation services and will tailor your OpenSim install to your specific needs. These companies all provide pricing on a per-server basis rather than per-region.

DeepThink (Managed OpenSim hosting and Customisation services):

ReactionGrid (Managed OpenSim hosting):

3Di (Customisation services, hosting. Tokyo based.):

Not listed here, but likely to offer these services are IBM, Tribal Media and Genkii.

Grid Hosting Providers

These companies provide hosting within the context of a grid. Most of these companies use very similarly specced hardware, however many of them share multiple clients per server – to use Second Life as an example, Linden Lab charges $295 per “island” which is stacked at 4 per server (or $1,180 per server per month).

While I did attempt to compile an exhaustive list of companies here – finding pricing and stacking ratios for many of them proved a difficult and time consuming process. You can find a more comprehensive list of grids (most of which offer region hosting), here:

Stability Remarks

As noted all over the OpenSimulator website – OpenSim is alpha quality software. To quote our downloads page

Please note: As OpenSim is still at an alpha code maturity stage, there is absolutely no guarantee that functionality works or is stable, even in the numbered releases. Certain features may not work either because the code is in rapid evolution, or because functionality expected by the Linden Labs Second Life viewer has simply not been implemented yet. However, constructive feedback is still welcomed.

If you are putting OpenSim into a production environment, make sure to speak with your hosting provider about what you plan to do – many of them may be able to make recommendations or tweaks to better suit your demands. If you have clients involved – it is often better to stick to an older more stable release as all releases are not nessecarily equal (eg 0.5.8 was somewhat stable, whereas 0.6.3 had appearance bugs).

If you are planning on using the ‘bleeding edge’ version of OpenSim in production, expect to get cut, or again quoting the downloads page:

There Be Dragons Beyond This Point

If you are truly feeling dangerous, adventurous, or want to help us test the next version of OpenSim you are welcome to grab the latest unstable code out of our subversion trunk. Any warnings previous expressed about the alpha nature of the code go double or triple if you are running directly off of trunk. Never, ever, ever, never run this in production environments, it is not suitable for that unless you are very familiar with the source code, and can hot fix any piece of it (that probably means you are an OpenSim core member). Feedback and testing on the unstable tree is appreciated, as that helps us make the next release better. If this scares you from using trunk, that was intended.

If it breaks, you get to keep both pieces.

Final Remarks

Running an Opensimulator instance can be a perfect fit for your organisation or person as long as you respect the limits. OpenSim can provide fantastic discounts to other commercial virtual worlds software, however it is worth remembering that it is still new and experimental – often this can be an advantage in customisability and features, but at the same time you need to respect the limitations of the software.

If you are unsure about whether to put OpenSim into production or how to do it in a way that fits what you need to do – like every Open Source piece of software, there are a lot of developers and organisations who can provide consulting services. Check the Core Developers List on the OpenSimulator wiki for a full list.

Adam Frisby

Adam Frisby is one of the founding developers of OpenSimulator, the open source platform for the 3D Internet. He is also the CEO of Sine Wave Entertainment, which specializes in specializes in creative design, content and software development for immersive virtual environments.