diff --git a/ucloud/host/main.py b/ucloud/host/main.py
index ca68351..0ca345b 100755
--- a/ucloud/host/main.py
+++ b/ucloud/host/main.py
@@ -8,7 +8,7 @@ from ucloud.common.request import RequestEntry, RequestType
 from ucloud.config import (vm_pool, request_pool,
                     etcd_client, running_vms,
                     etcd_wrapper_args, etcd_wrapper_kwargs,
-                    HostPool, env_vars)
+                    HostPool, config)
 
 from .helper import find_free_port
 from . import virtualmachine
@@ -18,7 +18,7 @@ from ucloud.host import logger
 def update_heartbeat(hostname):
     """Update Last HeartBeat Time for :param hostname: in etcd"""
     client = Etcd3Wrapper(*etcd_wrapper_args, **etcd_wrapper_kwargs)
-    host_pool = HostPool(client, env_vars.get('HOST_PREFIX'))
+    host_pool = HostPool(client, config['etcd']['HOST_PREFIX'])
     this_host = next(filter(lambda h: h.hostname == hostname, host_pool.hosts), None)
 
     while True:
@@ -72,7 +72,7 @@ def maintenance(host):
                 running_vms.remove(_vm)
 
 def check():
-    if env_vars.get('STORAGE_BACKEND') == 'filesystem' and not isdir(env_vars.get('VM_DIR')):
+    if config['etcd']['STORAGE_BACKEND'] == 'filesystem' and not isdir(config['etcd']['VM_DIR']):
         print("You have set STORAGE_BACKEND to filesystem. So, the vm directory mentioned"
               " in .env file must exists. But, it don't.")
         sys.exit(1)
@@ -84,7 +84,7 @@ def main(hostname):
 
     heartbeat_updating_process = mp.Process(target=update_heartbeat, args=(hostname,))
 
-    host_pool = HostPool(etcd_client, env_vars.get('HOST_PREFIX'))
+    host_pool = HostPool(etcd_client, config['etcd']['HOST_PREFIX'])
     host = next(filter(lambda h: h.hostname == hostname, host_pool.hosts), None)
     assert host is not None, "No such host with name = {}".format(hostname)
 
@@ -106,8 +106,8 @@ def main(hostname):
     # beat updating mechanism in separated thread
 
     for events_iterator in [
-        etcd_client.get_prefix(env_vars.get('REQUEST_PREFIX'), value_in_json=True),
-        etcd_client.watch_prefix(env_vars.get('REQUEST_PREFIX'), timeout=10, value_in_json=True),
+        etcd_client.get_prefix(config['etcd']['REQUEST_PREFIX'], value_in_json=True),
+        etcd_client.watch_prefix(config['etcd']['REQUEST_PREFIX'], timeout=10, value_in_json=True),
     ]:
         for request_event in events_iterator:
             request_event = RequestEntry(request_event)