Here’s why Solana (SOL) network crashed

September 21, 2021

Solana (SOL) suffered an outage of 17 hours last week with the servers overwhelmed and the network crashing. According to the network, this is a result of a denial-of-service attack aimed at Grape’s initial decentralised exchange (DEX) offering on the blockchain.

According to the Solana Foundation, the outage was caused by bots spamming the network as Grape launched its IDO on a Solana-based DEX (Raydium) last week. As per the blog overview of the occurrence, the bots flooded the network, slowing it down to an eventual stall:

At 12:00 UTC, Grape Protocol launched their IDO on Raydium, and bots generated transactions which flooded the network. These transactions created a memory overflow, which caused many validators to crash forcing the network to slow down and eventually stall.”

While the network and community took steps to address the issue, the attempts to recover the network were unsuccessful and the blockchain was faced with a number of forks automatically proposed to the network, causing the memory to run out and the network going offline for approximately 17 hours.

Solana crash, consensus resolution

Following the crash, engineers collaborated with validators to coordinate an upgrade-and-restart of the network, with a hard fork supported by 80% of the network.

[Engineers] from across the globe worked together to write code to mitigate the issue, and coordinate an upgrade-and-restart of the network among 1000+ validators… This was a coordinated effort by the community, not only in creating a patch, but in getting 80% of the network to come to consensus.”

The Solana Foundation also noted that during the attack, the network might have crashed but no funds were lost in the process. After 18 hours, the network returned to full functionality. The overview also indicated that the credit for restoring functionality goes to the Solana community. As a decentralized network, the effort is coordinated, rather than falling to a central entity to fix the problem.