Open Source Highly Available Storage Solutions?

Gunfighter asks: "I run a small data center for one of my customers, but they're constantly filling up different hard drives on different servers and then shuffling the data back and forth. At their current level of business, they can't afford to invest in a Storage Area Network of any sort, so they want to spread the load of their data storage needs across their existing servers, like Google does. The only software packages I've found that do this seamlessly are Lustre and NFS. The problem with Lustre is that it has a single metadata server unless you configure fail-over, and NFS isn't redundant at all and can be a nightmare to manage. The only thing I've found that even comes close is Starfish. While it looks promising, I'm wondering if anyone else has found a reliable solution that is as easy to set up and manage? Eventually, they would like to be able to scale from their current storage usage levels (~2TB) to several hundred terabytes once the operation goes into full production."

Re:Entry level SAN?

[jhines]

Solaris 10 is free these days. ZFS looks really good for this kind of application.

Re:Free is not necessarily as in free beer

[msporny]

Full Disclosure: I am one of the authors for the Starfish file system.

Software like Lustre and Starfish only wants you to help testing the software.

Both are not OSS in my opinion and not ready for the production.

Lustre is open-source and it has been production ready for years. The open source notice is on their website - GPL. You don't get much more open source than GPL. Lustre provides support to commercial enterprises.

As for Starfish, we eat our own dog food at our company. The newest version of Starfish will be taking over full-time for all of our HA storage systems in one months time. The website that runs on top of it is Bitmunk [bitmunk.com], our bread and butter. The license allows anybody to setup a small HA cluster for free. This is going to help a great deal of small websites and research institutions. If they want us to fix bugs that they find, we'll be more than happy to oblige. However, depending on your customers to find your bugs is not only a horrible business practice, it is reckless. We put ourselves at risk far before we make a release - if there is a bug, we're usually the first people to find it.

Please take a look at both sites more thoroughly.

Re:Take another look at NFS

[msporny]

I would not suggest cluster file systems such as Lustre for a small installation; they're generally designed to scale up to hundreds or thousands of servers, but not to scale down to a handful.

Our first Lustre cluster was 3 servers - it worked just fine. Starfish effortlessly scales down to 2 servers. Here is an example of it doing so:

Starfish Quickstart Tutorial [digitalbazaar.com]

Just because something scales to thousands of active nodes and disks, doesn't mean it can't scale down gracefully. The Internet is a good example of this concept.

Re:Entry level SAN?

[duffbeer703]

I respectfully disagree. Products like StarFish might make a storage highly available at a low price, but what about the other components of the system? If your network, app servers, etc aren't highly available, you have a whole new range of equipment and services that needs an HA solution as well.

I worked at a place where a $400 million project that spent tons of money on high availability database and server components was crippled by bad switches and application servers.