diff --git a/images_build/client/dign_client/bin/client.py b/images_build/client/dign_client/bin/client.py
index bb380ab..d3a3d29 100644
--- a/images_build/client/dign_client/bin/client.py
+++ b/images_build/client/dign_client/bin/client.py
@@ -379,14 +379,18 @@ def get_logger(name,logPath,enableConsole=True):
     return logger
 
 class DNSCheckRequestBuild:
+    def __init__(self):
+        self.dns_resolver=dns.resolver.Resolver()
+        self.dns_resolver.nameservers = DNS_SERVER_IP
+        self.dns_resolver.search = []
+        self.dns_resolver.use_search_by_default = False
+
     def dns_action_deny_subaction_drop(self,test_suite_name): 
-        dns_resolver=dns.resolver.Resolver()
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
 
         try:
-            dns_answer = dns_resolver.query(HOST_DNS_DENY_DORY, 'A')
+            dns_answer = self.dns_resolver.query(HOST_DNS_DENY_DORY, 'A')
         except dns.exception.DNSException as errorinfo:
             if type(errorinfo) == dns.resolver.LifetimeTimeout:
                 raise Exception(DnsRequestFirewallDenyDrop)
@@ -396,13 +400,11 @@ class DNSCheckRequestBuild:
             raise Exception("Error: The dns_action_deny_subaction_drop test deny drop failure" )
 
     def dns_action_deny_subaction_redirect_a(self,test_suite_name):
-        dns_resolver=dns.resolver.Resolver()
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
 
         try:
-            dns_answer = dns_resolver.query(HOST_DNS_DENY_REDIRECT_A, 'A')
+            dns_answer = self.dns_resolver.query(HOST_DNS_DENY_REDIRECT_A, 'A')
         except dns.exception.DNSException as errorinfo:
             raise Exception("Error: The dns_action_deny_subaction_redirect_a check failure, code: %s" % errorinfo)
         else:   # drop-redirect and respond rdtype A ipv4
@@ -419,14 +421,12 @@ class DNSCheckRequestBuild:
                    else:
                        raise Exception("Error: The dns request rdtype A drop redirect check failure: respond rdtype error")
 
-    def dns_action_deny_subaction_redirect_aaaa(self,test_suite_name):                                                                                            
-        dns_resolver=dns.resolver.Resolver()                                                                                                 
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                      
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                     
+    def dns_action_deny_subaction_redirect_aaaa(self,test_suite_name):                                                                                                                                                                                          
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                      
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                     
                                                                                                                                              
         try:                                                                                                                                 
-            dns_answer = dns_resolver.query(HOST_DNS_DENY_REDIRECT_AAAA, 'AAAA')                                                                    
+            dns_answer = self.dns_resolver.query(HOST_DNS_DENY_REDIRECT_AAAA, 'AAAA')                                                                    
         except dns.exception.DNSException as errorinfo:                                                                                      
             raise Exception("Error: The dns_action_deny_subaction_redirect_aaaa check failure, code: %s" % errorinfo)                                 
         else:   # drop-redirect and respond rdtype A ipv6                                                                                    
@@ -445,13 +445,11 @@ class DNSCheckRequestBuild:
                        raise Exception("Error: The dns request rdtype AAAA drop redirect check failure: respond rdtype error") 
 
     def dns_action_deny_subaction_redirect_a_rang_ttl(self,test_suite_name):
-        dns_resolver=dns.resolver.Resolver()
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
 
         try:
-            dns_answer = dns_resolver.query(HOST_DNS_DENY_REDIRECT_A_RTTL, 'A')
+            dns_answer = self.dns_resolver.query(HOST_DNS_DENY_REDIRECT_A_RTTL, 'A')
         except dns.exception.DNSException as errorinfo:
             raise Exception("Error: The dns_action_deny_subaction_redirect_a_rang_ttl check failure, code: %s" % errorinfo)
         else:   # drop-redirect and respond rdtype A ipv4
@@ -469,14 +467,12 @@ class DNSCheckRequestBuild:
                     else:
                         raise Exception("Error: The dns request rdtype A drop redirect range ttl check failure: respond rdtype error")
 
-    def dns_action_deny_subaction_redirect_aaaa_rang_ttl(self,test_suite_name):                                                                                            
-        dns_resolver=dns.resolver.Resolver()                                                                                                 
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                      
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                     
+    def dns_action_deny_subaction_redirect_aaaa_rang_ttl(self,test_suite_name):                                                                                                                 
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                      
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])                                                                                                     
                                                                                                                                              
         try:                                                                                                                                 
-            dns_answer = dns_resolver.query(HOST_DNS_DENY_REDIRECT_AAAA_RTTL, 'AAAA')                                                                    
+            dns_answer = self.dns_resolver.query(HOST_DNS_DENY_REDIRECT_AAAA_RTTL, 'AAAA')                                                                    
         except dns.exception.DNSException as errorinfo:                                                                                      
             raise Exception("Error: The dns_action_deny_subaction_redirect_aaaa range ttl check failure, code: %s" % errorinfo)                                 
         else:   # drop-redirect and respond rdtype A ipv6                                                                                    
@@ -497,13 +493,11 @@ class DNSCheckRequestBuild:
 
 
     def dns_action_allow_rdtype_a(self,test_suite_name):
-        dns_resolver=dns.resolver.Resolver()
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
 
         try:
-            dns_answer = dns_resolver.query(HOST_DNS_ALLOW_A, 'A')
+            dns_answer = self.dns_resolver.query(HOST_DNS_ALLOW_A, 'A')
         except dns.exception.DNSException as errorinfo:
             raise Exception("Error: The dns request rdtype A allow check failure, code: %s" % errorinfo)
         else:
@@ -523,13 +517,11 @@ class DNSCheckRequestBuild:
                         raise Exception("Error: The dns request rdtype A allow check failure: respond rdtype error")
  
     def dns_action_allow_rdtype_aaaa(self,test_suite_name):
-        dns_resolver=dns.resolver.Resolver()
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
 
         try:
-            dns_answer = dns_resolver.query(HOST_DNS_ALLOW_AAAA, 'AAAA')
+            dns_answer = self.dns_resolver.query(HOST_DNS_ALLOW_AAAA, 'AAAA')
         except dns.exception.DNSException as errorinfo:
             raise Exception("Error: The dns request rdtype AAAA allow check failure, code: %s" % errorinfo)
         else:
@@ -548,13 +540,11 @@ class DNSCheckRequestBuild:
                         raise Exception("Error: The dns request rdtype AAAA allow check failure: response rdtype error")
  
     def dns_action_allow_rdtype_cname(self,test_suite_name):
-        dns_resolver=dns.resolver.Resolver()
-        dns_resolver.nameservers = DNS_SERVER_IP
-        dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
-        dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.timeout = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
+        self.dns_resolver.lifetime = float(suite_test_config_dict[test_suite_name]['conn_timeout'])
 
         try:
-            dns_answer = dns_resolver.query(HOST_DNS_CNAME_QUERY, 'CNAME')
+            dns_answer = self.dns_resolver.query(HOST_DNS_CNAME_QUERY, 'CNAME')
         except dns.exception.DNSException as errorinfo:
             raise Exception("Error: The dns request rdtype CNAME allow check failure, code: %s" % errorinfo)
         else: