diff --git a/test/functional/test_framework/test_node.py b/test/functional/test_framework/test_node.py
index 37ef9c3b4..23b6ff2d5 100755
--- a/test/functional/test_framework/test_node.py
+++ b/test/functional/test_framework/test_node.py
@@ -1,325 +1,332 @@
 #!/usr/bin/env python3
 # Copyright (c) 2017 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Class for bitcoind node under test"""
 
 import decimal
 import errno
 import http.client
 import json
 import logging
 import os
 import re
 import subprocess
+import sys
 import time
 
 from .authproxy import JSONRPCException
 from .messages import COIN, CTransaction, FromHex
 from .util import (
     assert_equal,
     get_rpc_proxy,
     p2p_port,
     rpc_url,
     wait_until,
 )
 
 # For Python 3.4 compatibility
 JSONDecodeError = getattr(json, "JSONDecodeError", ValueError)
 
 BITCOIND_PROC_WAIT_TIMEOUT = 60
 
 
 class TestNode():
     """A class for representing a bitcoind node under test.
 
     This class contains:
 
     - state about the node (whether it's running, etc)
     - a Python subprocess.Popen object representing the running process
     - an RPC connection to the node
     - one or more P2P connections to the node
 
     To make things easier for the test writer, any unrecognised messages will
     be dispatched to the RPC connection."""
 
     def __init__(self, i, dirname, extra_args, host, rpc_port, p2p_port, timewait, binary, stderr, mocktime, coverage_dir, use_cli=False):
         self.index = i
         self.datadir = os.path.join(dirname, "node" + str(i))
         self.host = host
         self.rpc_port = rpc_port
         self.p2p_port = p2p_port
         self.name = "testnode-{}".format(i)
         if timewait:
             self.rpc_timeout = timewait
         else:
             # Wait for up to 60 seconds for the RPC server to respond
             self.rpc_timeout = 60
         if binary is None:
             self.binary = os.getenv("BITCOIND", "bitcoind")
         else:
             self.binary = binary
+        if not os.path.isfile(self.binary):
+            raise FileNotFoundError(
+                "Binary '{}' could not be found.\nTry setting it manually:\n\tBITCOIND=<path/to/bitcoind> {}".format(self.binary, sys.argv[0]))
         self.stderr = stderr
         self.coverage_dir = coverage_dir
         # Most callers will just need to add extra args to the default list
         # below.
         # For those callers that need more flexibity, they can access the
         # default args using the provided facilities
         self.extra_args = extra_args
         self.default_args = ["-datadir=" + self.datadir, "-server", "-keypool=1", "-discover=0", "-rest", "-logtimemicros",
                              "-debug", "-debugexclude=libevent", "-debugexclude=leveldb", "-mocktime=" + str(mocktime), "-uacomment=" + self.name]
 
-        self.cli = TestNodeCLI(
-            os.getenv("BITCOINCLI", "bitcoin-cli"), self.datadir)
+        cli_path = os.getenv("BITCOINCLI", "bitcoin-cli")
+        if not os.path.isfile(cli_path):
+            raise FileNotFoundError(
+                "Binary '{}' could not be found.\nTry setting it manually:\n\tBITCOINCLI=<path/to/bitcoin-cli> {}".format(cli_path, sys.argv[0]))
+        self.cli = TestNodeCLI(cli_path, self.datadir)
         self.use_cli = use_cli
 
         self.running = False
         self.process = None
         self.rpc_connected = False
         self.rpc = None
         self.url = None
         self.relay_fee_cache = None
         self.log = logging.getLogger('TestFramework.node{}'.format(i))
 
         self.p2ps = []
 
     def __getattr__(self, name):
         """Dispatches any unrecognised messages to the RPC connection or a CLI instance."""
         if self.use_cli:
             return getattr(self.cli, name)
         else:
             assert self.rpc is not None, "Error: RPC not initialized"
             assert self.rpc_connected, "Error: No RPC connection"
             return getattr(self.rpc, name)
 
     def clear_default_args(self):
         self.default_args.clear()
 
     def extend_default_args(self, args):
         self.default_args.extend(args)
 
     def remove_default_args(self, args):
         for rm_arg in args:
             # Remove all occurrences of rm_arg in self.default_args:
             #  - if the arg is a flag (-flag), then the names must match
             #  - if the arg is a value (-key=value) then the name must starts
             #    with "-key=" (the '"' char is to avoid removing "-key_suffix"
             #    arg is "-key" is the argument to remove).
             self.default_args = [def_arg for def_arg in self.default_args
                                  if rm_arg != def_arg and not def_arg.startswith(rm_arg + '=')]
 
     def start(self, extra_args=None, stderr=None, *args, **kwargs):
         """Start the node."""
         if extra_args is None:
             extra_args = self.extra_args
         if stderr is None:
             stderr = self.stderr
         self.process = subprocess.Popen(
             [self.binary] + self.default_args + extra_args,
             stderr=stderr, *args, **kwargs)
         self.running = True
         self.log.debug("bitcoind started, waiting for RPC to come up")
 
     def wait_for_rpc_connection(self):
         """Sets up an RPC connection to the bitcoind process. Returns False if unable to connect."""
         # Poll at a rate of four times per second
         poll_per_s = 4
         for _ in range(poll_per_s * self.rpc_timeout):
             assert self.process.poll(
             ) is None, "bitcoind exited with status {} during initialization".format(self.process.returncode)
             try:
                 self.rpc = get_rpc_proxy(rpc_url(self.datadir, self.host, self.rpc_port),
                                          self.index, timeout=self.rpc_timeout, coveragedir=self.coverage_dir)
                 self.rpc.getblockcount()
                 # If the call to getblockcount() succeeds then the RPC connection is up
                 self.rpc_connected = True
                 self.url = self.rpc.url
                 self.log.debug("RPC successfully started")
                 return
             except IOError as e:
                 if e.errno != errno.ECONNREFUSED:  # Port not yet open?
                     raise  # unknown IO error
             except JSONRPCException as e:  # Initialization phase
                 if e.error['code'] != -28:  # RPC in warmup?
                     raise  # unknown JSON RPC exception
             except ValueError as e:  # cookie file not found and no rpcuser or rpcassword. bitcoind still starting
                 if "No RPC credentials" not in str(e):
                     raise
             time.sleep(1.0 / poll_per_s)
         raise AssertionError("Unable to connect to bitcoind")
 
     def get_wallet_rpc(self, wallet_name):
         if self.use_cli:
             return self.cli("-rpcwallet={}".format(wallet_name))
         else:
             assert self.rpc_connected
             assert self.rpc
             wallet_path = "wallet/{}".format(wallet_name)
             return self.rpc / wallet_path
 
     def stop_node(self):
         """Stop the node."""
         if not self.running:
             return
         self.log.debug("Stopping node")
         try:
             self.stop()
         except http.client.CannotSendRequest:
             self.log.exception("Unable to stop node.")
         del self.p2ps[:]
 
     def is_node_stopped(self):
         """Checks whether the node has stopped.
 
         Returns True if the node has stopped. False otherwise.
         This method is responsible for freeing resources (self.process)."""
         if not self.running:
             return True
         return_code = self.process.poll()
         if return_code is None:
             return False
 
         # process has stopped. Assert that it didn't return an error code.
         assert_equal(return_code, 0)
         self.running = False
         self.process = None
         self.rpc_connected = False
         self.rpc = None
         self.log.debug("Node stopped")
         return True
 
     def wait_until_stopped(self, timeout=BITCOIND_PROC_WAIT_TIMEOUT):
         wait_until(self.is_node_stopped, timeout=timeout)
 
     def node_encrypt_wallet(self, passphrase):
         """"Encrypts the wallet.
 
         This causes bitcoind to shutdown, so this method takes
         care of cleaning up resources."""
         self.encryptwallet(passphrase)
         self.wait_until_stopped()
 
     def relay_fee(self, cached=True):
         if not self.relay_fee_cache or not cached:
             self.relay_fee_cache = self.getnetworkinfo()["relayfee"]
 
         return self.relay_fee_cache
 
     def calculate_fee(self, tx):
         # Relay fee is in satoshis per KB.  Thus the 1000, and the COIN added
         # to get back to an amount of satoshis.
         billable_size_estimate = tx.billable_size()
         # Add some padding for signatures
         # NOTE: Fees must be calculated before signatures are added,
         # so they will never be included in the billable_size above.
         billable_size_estimate += len(tx.vin) * 81
 
         return int(self.relay_fee() / 1000 * billable_size_estimate * COIN)
 
     def calculate_fee_from_txid(self, txid):
         ctx = FromHex(CTransaction(), self.getrawtransaction(txid))
         return self.calculate_fee(ctx)
 
     def add_p2p_connection(self, p2p_conn, *args, **kwargs):
         """Add a p2p connection to the node.
 
         This method adds the p2p connection to the self.p2ps list and also
         returns the connection to the caller."""
         if 'dstport' not in kwargs:
             kwargs['dstport'] = p2p_port(self.index)
         if 'dstaddr' not in kwargs:
             kwargs['dstaddr'] = '127.0.0.1'
 
         p2p_conn.peer_connect(*args, **kwargs)
         self.p2ps.append(p2p_conn)
 
         return p2p_conn
 
     @property
     def p2p(self):
         """Return the first p2p connection
 
         Convenience property - most tests only use a single p2p connection to each
         node, so this saves having to write node.p2ps[0] many times."""
         assert self.p2ps, "No p2p connection"
         return self.p2ps[0]
 
     def disconnect_p2ps(self):
         """Close all p2p connections to the node."""
         for p in self.p2ps:
             p.peer_disconnect()
         del self.p2ps[:]
 
 
 class TestNodeCLIAttr:
     def __init__(self, cli, command):
         self.cli = cli
         self.command = command
 
     def __call__(self, *args, **kwargs):
         return self.cli.send_cli(self.command, *args, **kwargs)
 
     def get_request(self, *args, **kwargs):
         return lambda: self(*args, **kwargs)
 
 
 class TestNodeCLI():
     """Interface to bitcoin-cli for an individual node"""
 
     def __init__(self, binary, datadir):
         self.args = []
         self.binary = binary
         self.datadir = datadir
         self.input = None
         self.log = logging.getLogger('TestFramework.bitcoincli')
 
     def __call__(self, *args, input=None):
         # TestNodeCLI is callable with bitcoin-cli command-line args
         cli = TestNodeCLI(self.binary, self.datadir)
         cli.args = [str(arg) for arg in args]
         cli.input = input
         return cli
 
     def __getattr__(self, command):
         return TestNodeCLIAttr(self, command)
 
     def batch(self, requests):
         results = []
         for request in requests:
             try:
                 results.append(dict(result=request()))
             except JSONRPCException as e:
                 results.append(dict(error=e))
         return results
 
     def send_cli(self, command, *args, **kwargs):
         """Run bitcoin-cli command. Deserializes returned string as python object."""
 
         pos_args = [str(arg) for arg in args]
         named_args = [str(key) + "=" + str(value)
                       for (key, value) in kwargs.items()]
         assert not (
             pos_args and named_args), "Cannot use positional arguments and named arguments in the same bitcoin-cli call"
 
         p_args = [self.binary, "-datadir=" + self.datadir] + self.args
         if named_args:
             p_args += ["-named"]
         p_args += [command] + pos_args + named_args
         self.log.debug("Running bitcoin-cli command: {}".format(command))
         process = subprocess.Popen(p_args, stdin=subprocess.PIPE,
                                    stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True)
         cli_stdout, cli_stderr = process.communicate(input=self.input)
         returncode = process.poll()
         if returncode:
             match = re.match(
                 r'error code: ([-0-9]+)\nerror message:\n(.*)', cli_stderr)
             if match:
                 code, message = match.groups()
                 raise JSONRPCException(dict(code=int(code), message=message))
             # Ignore cli_stdout, raise with cli_stderr
             raise subprocess.CalledProcessError(
                 returncode, self.binary, output=cli_stderr)
         try:
             return json.loads(cli_stdout, parse_float=decimal.Decimal)
         except JSONDecodeError:
             return cli_stdout.rstrip("\n")