InWorldz offers inventory backups to residents

In the wake of a massive data loss and ensuing grid shut down at What Virtual World, InWorldz announced yesterday that it will begin offering encrypted inventory backups to its residents.

The two events were not connected, InWorldz CTO David Daeschler told Hypergrid Business. He is also known as Tranquillity Dexler in-world.

David Daeschler

“The downloadable inventory backup files are something we’ve talked about with our customers as well as internally for a long time,” he said. “We’ve just finally gotten the time to complete the project.”

The InWorldz inventory exports are not to be confused with the IAR inventory archive files available elsewhere to OpenSim users. An IAR is a standard file that can be used to move content between grids. Some creators — including Linda Kellie and the users of OpenSim Creations — also use IAR downloads as a way to distribute content.

Instead, the InWorldz inventory export is a file specific to InWorldz and does not contain any assets.

“It is an encrypted, structure only dump of inventory to be used by InWorldz support and future tools that will be available on the InWorldz website for inventory management,” said Daeschler. “These files are not for use on other grids and don’t have all the data in them that would be required to use them in this manner.”

What the inventory backup file does is point to the assets, which are backed up separately.

If a resident accidentally deletes items from their inventory, or a viewer bug causes the items to disappear, the resident will be able to use the inventory backup file to get those items restored.

“You can never have enough backups,” Daeschler said.

He added that more import and export functionality will be added in the future, but declined to provide any details.

InWorldz recently rolled out its proprietary PhysX physics engine. (Image courtesy InWorldz.)

Redundant backups

According to Daeschler, InWorldz currently has around 6 terabytes of asset data, which is stored in seven different servers.

The servers are backed up continually, he said. If a single server goes down, there would be no loss of data, and users wouldn’t see any interruption in performance. In fact, two servers in each set of three can go down without any loss of data.

“All of the nodes in the cluster are also snapshotted regularly to recover in the event of a software malfunction that corrupts data,” he added.

There is also a separate set of backups for the regions themselves. These are automatic daily backups that generate a file similar to the standard OAR region archive, but customized to account for InWorldz physics and script state data.

“These files are stored for seven days, and our residents can choose to roll back to any previously available date,” said Daeschler.

Finally, the region data databases are also backed up, and the grid’s core data is both backed up and replicated.

Replication and backups serve two different purposes.

Replication works well to deal with hardware issues, since it provides an up-to-date, perfect copy of all the data.

But replication is not as useful if the data is corrupted or intentionally deleted, since the corruption or deletion will be replicated as well.

Good backups are important for any grid or hosting company, but are especially important for closed grids, where users are typically not allowed to make their own copies of their regions or avatar inventories in order to keep in-world content from being illegally copied.

Open grids, which allow users to connect their own regions and allow access to OpenSim region server consoles, also allow full export of regions and user inventories. Some hosting providers, such as Dreamland Metaverse, have these export options built into their region management consoles.

Other grids, such as Kitely, have begun experimenting with filtered exports. For example, since August 2011, Kitely has been allowing users to save content that they have created, or have copy and transfer permissions for, or that were specifically labeled as exportable by their creators. Kitely has donated this filtering code to the OpenSim community.

“We’ll be improving on the content protection system we already have in place once we add an ‘Export’ flag to content that will be sold via the upcoming Kitely Market,” Kitely CEO Ilan Tochner told Hypergrid Business.

Tochner also added that Kitely has plenty of internal backups and redundant systems, as well. “All Kitely data is stored in Amazon’s S3 cloud-based storage, meaning it is saved in multiple data centers around the world so even if multiple data centers are completely destroyed in some cataclysmic event the data should remain accessible. In addition, we save system  snapshots daily — retaining them for up to two weeks — so that we can revert the system, or a particular world [region or megaregion], to a previous state in case something bad happens to it.”

Eventually, standard OpenSim distributions and OpenSim-focused viewers may all support a fourth permission flag to the current set of “Copy,” “Transfer” and “Modify.” This fourth permission, “Export,” would allow users to save copies of content to their local hard drives, or to take it with them when traveling to other grids via hypergrid teleport.

However, even if other commercial grids adopt filtered exports, there will still be a need for a system like what InWorldz is offering, which allows residents to back up even protected, no-copy items.

Maria Korolov