Why can't I see block 1 on my local validator?

Question

I have solana-test-validator running locally.

And from https://explorer.solana.com, I can pick 'Custom RPC URL' and see the stats for my local validator. Clicking on the link for the current slot, I get https://explorer.solana.com/block/235965?cluster=custom&customUrl=http%3A%2F%2Flocalhost%3A8899

So far everything is fine.

If I manually change the URL to be https://explorer.solana.com/block/1?cluster=custom&customUrl=http%3A%2F%2Flocalhost%3A8899

I get:

Failed to fetch block

Why can't I see block I on my local validator?

Answer 1

The TestValidator doesn't keep ledger around forever. It is likely slot 1 was already pruned from yours. If you want to see what slots and roots you have locally, you can run solana-ledger-tool bounds -l <PATH_TO_YOUR_TEST_VALIDATOR>/test-ledger.