BSC-FAQ

[brilliant-lx]

Rationale

As the name suggested, this is to track the frequently asked question of BSC network.

FAQs

• Q1: About GasPrice order within a block
• Q2: How To Get tBNB
• Q3: Suggestion for running BSC nodes
• Q4: Node can not sync
• Q5: BSC no longer support light mode

Q1: About GasPrice order within a block & zero gas price

We saw complains from the community from time to time that some of the validators do not follow the GasPrice order, i.e. low GasPrice transactions are executed ahead of high GasPrice transactions within a block, which would lead to interest lose for some users.
But the problem is that GasPrice order is not part of the Parlia consensus, validators can sort the transaction with any order they want. Currently, it is the default behavior for validators to put high GasPrice transaction first. But if the validator thought it could got more rewards by arranging the transactions in different order, they could modify the code and no longer follow the default behavior. Most likely MEV related.
There is not much that chain dev team can help right now, except:

• raise a new proposal to put the GasPrice order as part of the consensus and to discuss with the community.
• notify the validators, hope the MEV solution could be updated to follow the GasPrice rule.

There were already many discussion on this topic before, track all related issues here:
#1170
#1171
#1706
#1746
#1945
#2349
#2397

And for Zero Gas Price issues, right now it is allowed from the consensus perspective. What the core team can do is quite limited, unless the community agree to change the consensus protocol to exclude zero gas price transactions.
#2371

Q2: How To Get tBNB

Sometimes there are complains that it is not easy to get enough tBNB, already we increased the claim amount from 0.1BNB to 0.3BNB, it could still not enough.
There are some good suggestions from the community, mark first, could improve the UX in the future.
Suggestion 1: #1673

Q3: Suggestion for running BSC nodes

refer: #875

Q4: Node can not sync?

• Case 1: sync from scratch(genesis)
  Generally, it could be caused by bad configure file or wrong startup arguments. You may just create an issue with your config.toml and your cmdline, we will help.
• Case 2: sync based on bsc-snapshot
  It could be caused by duplicated "<datadir>/geth/nodekey", which is used as the unique id of the peer in the whole network. The bsc-snapshot file should not contain the "nodekey" file, but sometime the maintainer could forget to delete it. You may just remove it "rm "<datadir>/geth/nodekey", the new nodekey will be generated automatically, so no worry. You may backup the nodekey file, if your nodeid is useful. Similar issue, see: v1.3.7 (pebbledb + PBSS): Peering issues - unable to connect or maintain peers #2145
• ** Case 3: sync for while, then failed to sync
  refer: bug: failed to discover more P2P nodes #1943, it is unknown yet, if you have similar issue, you may create a bug we will check.

Q5: BSC no longer support light mode

LES protocol has been broken after v1.3.0, the light mode can not be support, refer #2162
We have no plan to support it right now, if you do need it, you may let us know, we can consider how to meet your requirement.
Some discussion about LES from Geth team: https://gist.github.com/karalabe/184125637d587a16fe038f99a6daefea

[sniperbnb]

all those examples are from validators apart of bloxroute mev service (https://bsc.mev-explorer.blxrbdn.com/), it is basically a fork of eth flashbots so yes gas price order is not followed at the top of the block only. after it is as you would expect in a typical bsc block

[daron4ever]

we surely need a new proposal to put the GasPrice order for validators.

[zhk101]

Validator: Tranchess does it too

Gas price ordering is all over the place. Transaction postion 0 has a price of 0.1 gwei. Transaction on position 3 with 3 gwei was preceded by two failed tx with 42 and 47 gwei. That tx moves a lot of liquidity around which triggered mev bots following it with transactions with high gas price in between others with low gas price

https://bscscan.com/txs?block=34551530&p=3