I think this is something within my ability to add.
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The ability to change minrelaytxfee without restarting.
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I would like the ability to set the relayfee by a bitcoin-cli rpc call.
setminrelayfee amount
Set the transaction fee rate in BTC/kvB for this wallet. Overrides the global -setminrelayfee config parameter.
Can be deactivated by passing 0 as the fee. In that case automatic default min fee will be used.
Arguments:
1. amount (numeric or string, required) The transaction fee rate in BTC/kvB
Result:
true|false (boolean) Returns true if successful
Examples:
> bitcoin-cli setminrelayfee 0.00001
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id": "curltest", "method": "setminrelayfee", "params": [0.00001]}' -H 'content-type: text/plain;' http://127.0.0.1:8332/
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Additional context
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I encountered this while hooking up a lightning network node. My relay fee was too high from bad conf settings and was blocking funding transactions. I wasn't able to change this value and had to restart bitcoind instead of just making an rpc call.
