Default Mainnet RPC Issues - Experiencing Downtime or Heavy Rate Limiting

[highnet]

Hi viem developers and viem users,

I've been encountering issues with the default Mainnet RPC in viem. It seems to be either down or heavily rate-limited. My dAPP, which had been running smoothly before, started failing with errors related to RPC availability. Switching to another public RPC provider resolved the issue.

Here’s what I was doing with the default setup:

import { createPublicClient, http } from 'viem';
import { mainnet } from 'viem/chains';

const client = createPublicClient({
  chain: mainnet,
  transport: http(),
});

// Example query
async function getBlockNumber() {
  const blockNumber = await client.getBlockNumber();
  console.log('Current block number:', blockNumber);
}

getBlockNumber();

With the default Mainnet RPC, I noticed frequent failures, and I suspect it's due to rate-limiting or downtime on the public endpoint. After switching to another public RPC (e.g.,Ankr), everything worked fine:

const client = createPublicClient({
  chain: mainnet,
  transport: http('https://rpc.ankr.com/eth'),
});

This immediately resolved the issue.

Questions for the Community

• Is anyone else experiencing similar issues with the default Mainnet RPC in viem?
  What’s the actual default RPC endpoint being used for Mainnet? I couldn’t find this clearly documented.
• Do you recommend sticking with the default RPC for production applications, or should we always use a custom RPC (e.g., Ankr)?
• Any advice or recommendations on handling RPC reliability for viem-based applications would be greatly appreciated.

Thanks in advance for your help!

[tmm]

When you don't provide your own RPC URL (e.g. http()), Viem uses the default public RPC URL. These are shared resources so they can be okay for prototyping, but should not be used for production applications.

[highnet]

Thanks for the quick response.