bitcoind + testnet on same machine fails when zmq is active #12481

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Trying to run bitcoind node and a testnet node on the same machine, but starting testnet fails when zmq is active

$ bitcoind  -testnet
bitcoind: zmq/zmqpublishnotifier.cpp:104: virtual void CZMQAbstractPublishNotifier::Shutdown(): Assertion `psocket' failed.
Aborted (core dumped)

When zmqnotifications is configured only on mainnet, the testnet fails to start (even when zmq is disabled or configured with different port on testnet).

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<!-- What version of Bitcoin Core are you using, where did you get it (website, self-compiled, etc)? -->

0.16rc4

<!-- What type of machine are you observing the error on (OS/CPU and disk type)? -->

ubuntu 16.04

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<!--- This is normally the contents of a `debug.log` or `config.log` file. Raw text or a link to a pastebin type site are preferred. -->

Can you post the configuration and debug.log?

testnet3/debug.log

2018-02-21 08:27:33 Bitcoin Core version v0.16.0rc4 (release build)
2018-02-21 08:27:33 InitParameterInteraction: parameter interaction: -whitelistforcerelay=1 -> setting -whitelistrelay=1
2018-02-21 08:27:33 Assuming ancestors of block 0000000002e9e7b00e1f6dc5123a04aad68dd0f0968d8c7aa45f6640795c37b1 have valid signatures.
2018-02-21 08:27:33 Setting nMinimumChainWork=00000000000000000000000000000000000000000000002830dab7f76dbb7d63
2018-02-21 08:27:33 Using the 'standard' SHA256 implementation
2018-02-21 08:27:33 Default data directory /home/user/.bitcoin
2018-02-21 08:27:33 Using data directory /home/user/.bitcoin/testnet3
2018-02-21 08:27:33 Using config file /home/user/.bitcoin/bitcoin.conf
2018-02-21 08:27:33 Using at most 125 automatic connections (1024 file descriptors available)
2018-02-21 08:27:33 Using 16 MiB out of 32/2 requested for signature cache, able to store 524288 elements
2018-02-21 08:27:33 Using 16 MiB out of 32/2 requested for script execution cache, able to store 524288 elements
2018-02-21 08:27:33 Using 2 threads for script verification
2018-02-21 08:27:33 scheduler thread start
2018-02-21 08:27:33 Binding RPC on address 0.0.0.0 port 18332 failed.
2018-02-21 08:27:33 HTTP: creating work queue of depth 16
2018-02-21 08:27:33 Config options rpcuser and rpcpassword will soon be deprecated. Locally-run instances may remove rpcuser to use cookie-based auth, or may be replaced with rpcauth. Please see share/rpcuser for rpcauth auth generation.
2018-02-21 08:27:33 HTTP: starting 4 worker threads
2018-02-21 08:27:33 Using wallet directory /home/user/.bitcoin/testnet3
2018-02-21 08:27:33 init message: Verifying wallet(s)...
2018-02-21 08:27:33 Using BerkeleyDB version Berkeley DB 4.8.30: (April  9, 2010)
2018-02-21 08:27:33 Using wallet wallet.dat
2018-02-21 08:27:33 CDBEnv::Open: LogDir=/home/user/.bitcoin/testnet3/database ErrorFile=/home/user/.bitcoin/testnet3/db.log

testnet3/bitcoin.conf

listen=1
rpcport=8444
testnet=1
checkblocks=50
#zmqpubrawtx=tcp://127.0.0.1:28441
#zmqpubhashtx=tcp://127.0.0.1:28442
#zmqpubhashblock=tcp://127.0.0.1:28443
#zmqpubrawblock=tcp://127.0.0.1:28444
#zmqpubrawtx=tcp://127.0.0.1:28445

[update].. ok, I noticed it does not automatically look for a bitcoin.conf file in the testnet3/ folder, so it reads the regular conf. I guess it works as expected, and I have to add the location of the testnet conf using the -conf= option