Sepolia post-merge upgrade announced | Ethereum Foundation Blog

adminDecember 14, 2023

The Sepolia testnet undergoes execution layer (EL) upgrade after merging from blocks. 1735371Scheduled for August 17, 2022
The upgrade will cause EL clients on the network to lose connectivity to peers that have not converted to proof-of-stake. Other than this it doesn’t add any additional features.
Sepolia node operators must upgrade their execution layer clients prior to blocking. 1735371.
Similar upgrades are expected for Goerli and Ethereum mainnets once these networks transition to proof-of-stake.

background

To maintain a healthy peer list, nodes in the Ethereum execution layer automatically disconnect peers that do not have the same upgrade order. On the Ethereum mainnet, this means checking if a peer has been upgraded to: frontier thaw At block 200,000 house It continues from block 1,150,000 until the latest upgrade. gray glacierThis occurred at block 15,050,000. EIP-2124 Specifies how this is handled. In a typical network upgrade triggered by block height, this happens automatically, as nodes use the block height of future upgrades to filter peers.

For The Merge, this was not possible because the upgrade was triggered using: total difficulty This is a value, not a block number. The rationale for this choice is explained next. EIP-3675:

Using predefined block numbers for hard forks is unsafe in this context because the PoS fork selection takes precedence during the transition.

An attacker can use a small number of hash powers to build a malicious chain fork that meets the block height requirements. The first PoS block could then be maliciously proposed on top of the PoW block of this hostile fork, becoming the leader and destroying the security of the transition.

To protect the network from this attack scenario, we use the accumulated difficulty in the chain (total difficulty) to trigger an upgrade.

To minimize protocol changes during the most complex upgrade since launch, The Merge’s design excluded EIP-2124 compatibility. This means that you will now need to perform a further upgrade to add it. The only change introduced as part of this upgrade is specifying a block number that nodes can use to identify peers that have undergone a merge. As part of this upgrade, other features are introduced or deprecated.

Upgrade information

timing

This upgrade takes place in the Sepolia block. 1735371It is expected to be held on August 17, 2022.

Similar upgrades will be announced for Goerli and mainnet after these networks transition to proof-of-stake.

Ropsten ~ no It is now considered obsolete along with Rinkeby and Kiln and needs to be upgraded. see this post Learn more about the deprecation schedule.

client release

This upgrade only requires updating the execution layer client. Node operators will be able to continue running their current consensus layer client releases on Sepalia through the transition.

Client releases are used to: Görli/Prater Merge all of these upgrades in Sepalia. This means that if you have already downloaded the release for the Goerli/Prater merge, you can use the same version from Sepolia for this upgrade.

execution layer

Upgrade specifications

The specification for this change is tracked as part of: fly Specifications, below Fork Next Upgrade part time job.

frequently asked questions

What do I do as a node operator?

You must upgrade your execution tier client to one of the versions listed above before August 16, 2022. Consensus layer clients do not need to upgrade.

What should I do as a staker?

Validators set up on Sepolia are licensed. If you are currently part of the Sepalia validator, you must update your execution layer client to one of the versions listed above no later than August 16, 2022.

If you are not currently part of the Sepalia validator set, you do not need to do anything now.

Goerli/Prater and mainnet validators must follow the same steps when this upgrade is announced on their respective networks.