Stellar was down for 2 hours "caused by being too decentralized too fast"

Stellar network went down at 4:15 p.m. ET for nearly two hours Wednesday as enough nodes "stopped for various reasons" and the network halted. The network couldn't reach consensus and no transactions were validated in that time period. 

Jed McCaleb, co-founder of Stellar, told The Block: "Over the last months we have worked to get people to not depend on the SDF nodes. As of maybe a month or so ago the SDF nodes could safely go down and the network would continue. But this also means that the network can halt even if the SDF nodes are still running. Unfortunately this is what happened."

The SDF nodes and the majority of validators in the network were running, according to Stellar, but they couldn't close ledgers safely because they weren't hearing from enough nodes in their quorums.

Nicolas Barry, CTO of Stellar, said more information about the issues will be forthcoming "in the next few days" including the steps that Stellar is going to take to address them. Barry said: "All I can say right now is that it was caused by being too decentralized too fast and the system behaved the right way by halting." The price of Stellar lumens (XLM) is up 20% since this incident.

Updated with a statement from Jed McCaleb. The previous version imprecisely described that the reason the network went down was because SDF nodes were down, which was not the case.