But the board, which has a history of use by violent extremists, also quickly found a new online host. That company also provides such support for Gab.com, another social media site frequented by white supremacists that doesn't ban hate speech.
8chan was up and down after the security company Cloudflare said it would no longer provide services that protect web sites from denial-of-service attacks that can make them unreachable.
The operators of 8chan said there might be downtime in the next one or two days as the site sought a solution, and online records indicated the site had been moved to a new domain host: Sammamish, Washington-based web services provider Epik.com.
The company bills itself on its site as "the Swiss bank of domains." Epik.com did not immediately respond to requests sent by email and via LinkedIn.
Police are investigating commentary posted on 8chan and believed to have been written by the suspect in a shooting Saturday that killed 20 people in El Paso, Texas.
If there is a connection, it would be the third known instance of a shooter posting to the site before going on a rampage following mass shootings at two New Zealand mosques in the spring, and another at a California synagogue.
The suspect in El Paso "appears to have been inspired" by discussions on 8chan, said Cloudflare CEO Matthew Prince in a blog post on his company's site. He said a suspect in an earlier shooting at a synagogue in Poway, California, also posted a "hate-filled `open letter"' on 8chan, as did the mosque attacker in Christchurch, New Zealand.
"8chan has repeatedly proven itself to be a cesspool of hate," wrote Prince. "They have proven themselves to be lawless and that lawlessness has caused multiple tragic deaths."
Prince acknowledged that little can be done under current rules to silence sites like 8chan.
With the big social networks doing a better job of moderating hate speech, incitement to violence and harassment, it's inevitable that extreme speech is gravitating to smaller websites that are often little more than message boards -- sites teenagers routinely make in their bedrooms, said Joan Donovan, the director of the technology and social change project at Harvard University's Kennedy School of Government.
Services like Cloudflare or BitMitigate that host and protect websites are necessary to keep contentious, extremist-tolerant message boards like 8chan online because they typically attract hostile traffic from hacktivists aimed at overwhelming the sites and making them unreachable.
"That's precisely the paradox that Cloudfare finds itself in," Donovan said. "It sees itself as a necessary part of the internet infrastructure while at the same time understanding that in providing protection to these hate sites they are in some cases one of the reasons this content continues to exist or continues to stay online."
Two years ago, Cloudflare terminated service to the Daily Stormer, a neo-Nazi and white supremacist site.
"Today, the Daily Stormer is still available and still disgusting," Prince wrote. "They have bragged that they have more readers than ever. They are no longer Cloudflare's problem, but they remain the Internet's problem."
In fact, the Daily Stormer's new security provider, BitMitigate, was purchased in February by Epik.com , whose CEO is Robert Monster of Bellevue, Washington.
In November, Monster defended in a blog post his company's decision to host Gab.com after its previous domain host, GoDaddy, dropped it.
WHAT IS 8CHAN?
The online message board dates back to 2013. Under the banner of free speech, it allows users to post graphic and extremist content and doesn't censor posts.
The site has been linked to violent extremists. Police are investigating commentary posted on 8chan believed to have been written by the suspect in a shooting Saturday that killed 22 people in El Paso, Texas.
If there is a connection, it would be the third known instance of a shooter posting to the site before going on a rampage. In March, the gunman in mass shootings at two New Zealand mosques posted a rambling manifesto to the site, as did another who injured several people and killed one at a California synagogue in April.
8chan's founder, Fredrick Brennan, is no longer running the site. In an interview with The New York Times on Monday, he said the site wasn't doing any good and called for it to be shut down .
WHY DID 8CHAN GO DOWN?
The site went down briefly after security provider Cloudflare said it would stop supporting the site. Without Cloudflare, the site was vulnerable to outside hackers who shut down the site.
"8chan has repeatedly proven itself to be a cesspool of hate," Cloudflare CEO Matthew Prince wrote. "They have proven themselves to be lawless and that lawlessness has caused multiple tragic deaths."
CAN 8CHAN BE SHUT DOWN?
8chan's popularity rose after the similarly named but unaffiliated site 4chan cracked down on more extreme posts. Because the U.S. doesn't specifically outlaw domestic terrorism the way it does foreign-sponsored extremism, such sites enjoy broad protection from government oversight under the U.S. Constitution's First Amendment.
Even if that weren't the case, content on sites like 8chan are also difficult to stamp out because users can simply move on if moderators grow stricter or if a site shuts down.
"Dealing with incitement to violence and hatred online goes well beyond any one platform," the Anti-Defamation League's Oren Segal said.
"These hate and racist posts will find another way to get their message out and another site with less scruples will pop up to host them," added Tim Bajarin, a technology columnist and president of Creative Strategies. "The internet has always been a Wild, Wild West medium with very little controls to keep this type of harmful commentary from seeing the light of day."
WHAT ABOUT REGULATION?
Mutale Nkonde, a fellow at the Berkman Klein Center at Harvard, said it's time to think about creating a legal definition for harmful speech that could be regulated.
"We need to seriously balance do we want to be secure as a nation and have the ability to go to Walmart or we want to protect the speech of those who want to destroy our country from within?" she said.
But there has been resistance to passing legislation, said David Kaye, the U.N. special rapporteur on freedom of expression and a University of California-Irvine law professor.
"It's very difficult to get any kind of law adopted in the United States," Kaye said. "Even after these terrible crimes and the connection the 8chan forum has to them, I don't see much of a likelihood of a pretty serious debate about how the companies should be regulated."
Kaye said that in the absence of U.S. government action on online speech, the most Americans can hope for is that companies like Cloudflare are transparent about their policies regarding hate speech -- and what should be regarded as incitement to violence and not tolerated.
"There is probably horrible content that's being hosted by its clients in other parts of the world," he said, "but is it applying the same measures there?"