---
# System prepended metadata

title: '**BELOW IS OUTDATED**'

---

Question:
**What is a parent to block production? Possible pending parent, or confirmed one?**

ANSWER:
**Neither**
We must pass block parent block hash to Pandora eth_getWork






**BELOW IS OUTDATED**
==========================================================
Block production

Actors:
A,B,C, D

SLOT
1 A PANDORA BLOCK NUMBER 1 -> 0xa......... -> signed
2 B Received the block number 1 -> 0xa -> signed (PENDING) -> He must produce a new block. What is a block number at eth_getWork => 1 invalid => 0xb
3 C Received block number 1 => 0xa , number 1 => 0xb both are pending, I must produce a block, so i produce block number 1 again 0xc
4 B ->... received number(s) 1 0xa, 0xb, 0xc => produces block number 1 0xd
5 A ->... received number(s) 1 0xa, 0xb, 0xc, 0xd => produces block number 1 0xf
6 C ->... received number(s) 1 0xa, 0xb, 0xc, 0xd, 0xf => produces block number 1 0xaa
7 D 0xa block number 1 cannonical, slots from 2-6 are not cannocical, they are discarded and slashed [0xb, 0xc, 0xd, 0xf, 0xaa]

```go=
type header struct {
    number: int
    parentHash: common.Hash
    extraData: [
        ...
        ...
        signature [96]byte
    ]
}
```

