Polygon’s Network was down from 5:50 PM UTC on March 10th until about 4 AM UTC on March March 11th. All users’ funds are safe, and the team explained the particular issues for which the network was not operational during these 11 hours.
The cause of the polygon problem
Yesterday, Polygon developers notified users of a potential upcoming downtime for the network due to a planned network upgrade – the Heimdall node.
The Heimdall implementation is used by one of the two layers of the network’s proof-of-stake chain. The team confirmed the downtime at 5:50 PM UTC on March 10th, providing further clarifications. It’s worth noting that no user funds were compromised during the outage.
While we are working to identify the definitive cause, it appears to be from an earlier update consisting of a minot setting fix of the Ethereum to Polygon PoS state sync/bridging module.
The team also revealed that there “may have been a bug” in the upgrade, which had an effect on the consensus and led to different Heimdall validators being on different versions of the blockchain. This prevented them from reaching the 2/3 consensus.
When using bidding consensus, this situation will cause the Heimdall chain to stop.
The developers also reaffirmed that Heimdall doesn’t handle user transactions but is used for validator-related bridging and transactions.
Additionally, the team explained that the Bor chain, which is Polygon’s PoS chain for users, was also discontinued because it relies on Heimdall for “block proposal committee selection.”
Polygon’s Temporary Hotfix
At around 4 AM UTC on March 11th, the team successfully released a hotfix which restored operations on Polygon’s network, although the Bridge itself “will not be active until we fully resolve the issue,”
The most recent update reads:
We appreciate your support during this time and have an update: we have deployed a temporary hotfix to unblock the Bor chain and resume producing blocks on the Polygon chain. While this solution is temporary, the team is working on implementing a longer-term upgrade to fix the Heimdall issue.
The network bridge, however, will not be active until the final solution is released.
