On Rinkeby, after I deploy my gas limit is low for function, even though it was high when I deployed

Question

I deployed my smart contracts to Rinkeby. I made my gas limit 3000000 in truffle.js like so:

rinkeby: {
  host: "localhost",
  port: 8545,
  network_id: 4,
  gas: 3000000
}

On Etherscan, it shows my gas limit is indeed 3000000. But when I try to use some functions, I exceed the gas limit. On etherscan it shows my gas limit is only 9000 and I exceeded it

Gas Limit: 90000

Gas Used By Transaction:90000 (100%)

As a result, the transaciton fails. Why is this the case?

Answer 1

The gas limit is a property of each transaction. So you set a high gas limit for the transaction where you deployed the contract, but you're setting a lower gas limit on the transactions where you're using the contract.

Most tools/code for sending transactions should be able to automatically estimate the gas limit you need. Without specifics of how you're sending these transactions, it's hard to make further suggestions.