How to change RPC port for bitcoind? (rpcport=xxx in bitcoin.conf doesn't work)
Found the solution: rpcport needs to be in the [test] section

Please update your original config file to read:


testnet=1
server=1
daemon=1
txindex=1
rpcuser=XXXXXXXXXXXXXXXXXXXXXXX
rpcpassword=XXXXXXXXXXXXXXXXXXX
rpcallowip=127.0.0.1
onlynet=ipv4
zmqpubrawblock=tcp://127.0.0.1:28332
zmqpubrawtx=tcp://127.0.0.1:28333
[test]
rpcport=19832


And restart the daemon. Also take a look at Can&#39;t specify rpcport for testnet for related changes to other options. We were being warned what to do in the log file. ~/.bitcoin/testnet3/debug.log includes the line Warning: Config setting for -rpcport only applied on test network when in [test] section.

We could have picked this up faster had (we read the log file! And if) the example bitcoin.conf made a mention of now requiring sections. 

Would be great if you could make this the ticked solution instead!