diff --git a/proxybroker/api.py b/proxybroker/api.py
index 9c94247..cb99f75 100644
--- a/proxybroker/api.py
+++ b/proxybroker/api.py
@@ -43,6 +43,8 @@ class Broker:
         (optional) Flag indicating whether to check the SSL certificates.
         Set to True to check ssl certifications
     :param loop: (optional) asyncio compatible event loop
+    :param stop_broker_on_sigint: (optional) whether set SIGINT signal on broker object. 
+        Useful for a thread other than main thread.
 
     .. deprecated:: 0.2.0
         Use :attr:`max_conn` and :attr:`max_tries` instead of
@@ -59,6 +61,7 @@ def __init__(
         providers=None,
         verify_ssl=False,
         loop=None,
+        stop_broker_on_sigint=True,
         **kwargs,
     ):
         self._loop = loop or asyncio.get_event_loop()
@@ -101,13 +104,13 @@ def __init__(
             p if isinstance(p, Provider) else Provider(p)
             for p in (providers or PROVIDERS)
         ]
-
-        try:
-            self._loop.add_signal_handler(signal.SIGINT, self.stop)
-            # add_signal_handler() is not implemented on Win
-            # https://docs.python.org/3.5/library/asyncio-eventloops.html#windows
-        except NotImplementedError:
-            pass
+        if stop_broker_on_sigint:
+            try:
+                self._loop.add_signal_handler(signal.SIGINT, self.stop)
+                # add_signal_handler() is not implemented on Win
+                # https://docs.python.org/3.5/library/asyncio-eventloops.html#windows
+            except NotImplementedError:
+                pass
 
     async def grab(self, *, countries=None, limit=0):
         """Gather proxies from the providers without checking.
diff --git a/proxybroker/resolver.py b/proxybroker/resolver.py
index 1a661d4..80c304c 100644
--- a/proxybroker/resolver.py
+++ b/proxybroker/resolver.py
@@ -36,6 +36,8 @@ class Resolver:
         'http://ipinfo.io/ip',
         'http://ifconfig.io/ip',
     ]
+    # the list of resolvers will point a copy of original one
+    _temp_host = []
 
     def __init__(self, timeout=5, loop=None):
         self._timeout = timeout
@@ -85,13 +87,16 @@ def get_ip_info(ip):
         return GeoData(code, name, region_code, region_name, city_name)
 
     def _pop_random_ip_host(self):
-        host = random.choice(self._ip_hosts)
-        self._ip_hosts.remove(host)
+        host = random.choice(self._temp_host)
+        self._temp_host.remove(host)
         return host
 
     async def get_real_ext_ip(self):
         """Return real external IP address."""
-        while self._ip_hosts:
+        # make a copy of original one to temp one
+        # so original one will stay no change
+        self._temp_host = self._ip_hosts.copy()
+        while self._temp_host:
             try:
                 timeout = aiohttp.ClientTimeout(total=self._timeout)
                 async with aiohttp.ClientSession(