Yesterday The Pirate Bay was raided for the second time in its history and millions of people are still anxiously waiting to see whether the "most resilient" site can make a comeback. At the same time, other torrent sites are noticing a big spike in traffic.

In recent years The Pirate Bay took several steps to make the site as resilient as possible, moving from a full-fledged BitTorrent tracker to a trimmed-down and highly portable torrent index.

The infamous torrent site canceled nearly all central servers and moved most of its operation to the cloud, where it ran on 21 virtual machines scattered over several commercial cloud hosting providers.

Yesterday, however, the site was pulled offline with a single raid at the Nacka station, a nuclear-proof data center built into a mountain complex. Despite various rumors of TPB reincarnations there is still no sign that the site will return anytime soon.

So how can it be that The Pirate Bay was taken down despite all the time and effort that went into making its setup raid proof?

TF has been speaking with various people familiar with the matter and one of the most likely scenarios emerging is that the site’s loadbalancer was hit by the raid. This has been one of the remaining bottlenecks for TPB in recent years and the cause of previous downtime.

If this theory holds true it should be possible for the site to recover quickly if a new loadbalancer with the right setup is put in place. After all, the virtual machines are not centrally hosted and should be up and running.

How long it will take to connect these to the Internet remains guesswork for now, if it happens at all.

At the moment it’s still unknown what Pirate Bay-related hardware was seized during the raid. The Pirate Bay team previously stressed, however, that everything is encrypted in case it falls into the wrong hands.

On the human front, the police arrested one member of the Pirate Bay crew yesterday. The identity of this person hasn’t been confirmed, but if it’s one of the people with access to the site’s crucial infrastructure it will further complicate any possible comeback.

Another concern is that the people running TPB and other sites affected by the raid are also remaining quiet. The popular TV-torrent site EZTV remains offline too and thus far the operator is not commenting on the situation.

Meanwhile, most other torrent sites are seeing a spike in traffic from Pirate Bay users looking for a new home. TorrentReactor and other large torrent sites inform TF that there’s an increase in traffic of between 5 and 10 percent at the moment.

After the first raid in 2006 it took The Pirate Bay three days to recover, making a blazing comeback as “The Police Bay.” There’s not long left to beat that record.

Update: Just to be clear, thepiratebay.ee, thepiratebay.cr, thepiratebay.mobi and others are mirrors not affiliated with the original site. They serve old content (no new uploads) and are not TPB resurrections. If the site reappears it will be on the original .se domain.