diff --git a/dns.c b/dns.c
index 8d40ee6..8c24391 100644
--- a/dns.c
+++ b/dns.c
@@ -17,6 +17,7 @@
  */
 
 #include "dns.h"
+#include "tlog.h"
 #include <stdio.h>
 #include <string.h>
 
@@ -515,6 +516,9 @@ int _dns_decode_domain(struct dns_context *context, char *output, int size)
 	int is_compressed = 0;
 
 	while (1) {
+		if (ptr > context->data + context->maxsize || ptr < context->data) {
+			return -1;
+		}
 		len = *ptr;
 		if (len == 0) {
 			*(output - 1) = 0;
@@ -528,21 +532,27 @@ int _dns_decode_domain(struct dns_context *context, char *output, int size)
 				context->ptr = ptr;
 			}
 			ptr = context->data + len;
-			if (context->maxsize - (ptr - context->data) < 1) {
+			if (context->maxsize - (ptr - context->data) < 0) {
+				tlog(TLOG_ERROR, "length is not enouth %d:%d, %p, %p", context->maxsize, ptr-context->data, 
+					context->ptr, context->data);
 				return -1;
 			}
 			is_compressed = 1;
 			continue;
 		}
 
-		if (context->maxsize - (ptr - context->data) < 1) {
+		if (context->maxsize - (ptr - context->data) < 0) {
+			tlog(TLOG_ERROR, "length is not enouth %d:%d, %p, %p", context->maxsize, ptr-context->data, 
+					context->ptr, context->data);
 			return -1;
 		}
 
 		ptr++;
 		if (output_len < size - 1) {
 			copy_len = (len < size - output_len) ? len : size - 1 - output_len;
-			if (context->maxsize - (ptr - context->data) < 1) {
+			if (context->maxsize - (ptr - context->data) < 0) {
+				tlog(TLOG_ERROR, "length is not enouth %d:%d, %p, %p", context->maxsize, ptr-context->data, 
+					context->ptr, context->data);
 				return -1;
 			}
 			memcpy(output, ptr, copy_len);
@@ -594,10 +604,12 @@ int _dns_decode_qr_head(struct dns_context *context, char *domain, int domain_si
 
 	ret = _dns_decode_domain(context, domain, domain_size);
 	if (ret < 0) {
+		tlog(TLOG_ERROR, "decode domain failed.");
 		return -1;
 	}
 
 	if (_dns_left_len(context) < 4) {
+		tlog(TLOG_ERROR, "left length is not enough, %s.", domain);
 		return -1;
 	}
 
@@ -631,10 +643,12 @@ int _dns_decode_rr_head(struct dns_context *context, char *domain, int domain_si
 
 	len = _dns_decode_qr_head(context, domain, domain_size, qtype, qclass);
 	if (len < 0) {
+		tlog(TLOG_ERROR, "decode qr head failed.");
 		return -1;
 	}
 
 	if (_dns_left_len(context) < 6) {
+		tlog(TLOG_ERROR, "left length is not enough.");
 		return -1;
 	}
 
@@ -873,6 +887,7 @@ int _dns_decode_an(struct dns_context *context, dns_rr_type type)
 
 	ret = _dns_decode_rr_head(context, domain, DNS_MAX_CNAME_LEN, &qtype, &qclass, &ttl, &rr_len);
 	if (ret < 0) {
+		tlog(TLOG_ERROR, "decode head failed.");
 		return -1;
 	}
 	start = context->ptr;
@@ -882,11 +897,13 @@ int _dns_decode_an(struct dns_context *context, dns_rr_type type)
 		unsigned char addr[DNS_RR_A_LEN];
 		ret = _dns_decode_A(context, addr);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode A failed, %s", domain);
 			return -1;
 		}
 
 		ret = dns_add_A(packet, type, domain, ttl, addr);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "add A failed, %s", domain);
 			return -1;
 		}
 	} break;
@@ -894,11 +911,13 @@ int _dns_decode_an(struct dns_context *context, dns_rr_type type)
 		char cname[DNS_MAX_CNAME_LEN];
 		ret = _dns_decode_CNAME(context, cname, DNS_MAX_CNAME_LEN);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode CNAME failed, %s", domain);
 			return -1;
 		}
 
 		ret = dns_add_CNAME(packet, type, domain, ttl, cname);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "add CNAME failed, %s", domain);
 			return -1;
 		}
 	} break;
@@ -906,11 +925,13 @@ int _dns_decode_an(struct dns_context *context, dns_rr_type type)
 		char ns[DNS_MAX_CNAME_LEN];
 		ret = _dns_decode_CNAME(context, ns, DNS_MAX_CNAME_LEN);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode NS failed, %s", domain);
 			return -1;
 		}
 
 		ret = dns_add_NS(packet, type, domain, ttl, ns);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "add NS failed, %s", domain);
 			return -1;
 		}
 	} break;
@@ -918,11 +939,13 @@ int _dns_decode_an(struct dns_context *context, dns_rr_type type)
 		char name[DNS_MAX_CNAME_LEN];
 		ret = _dns_decode_PTR(context, name, DNS_MAX_CNAME_LEN);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode PTR failed, %s", domain);
 			return -1;
 		}
 
 		ret = dns_add_PTR(packet, type, domain, ttl, name);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "add PTR failed, %s", domain);
 			return -1;
 		}
 	} break;
@@ -930,11 +953,13 @@ int _dns_decode_an(struct dns_context *context, dns_rr_type type)
 		unsigned char addr[DNS_RR_AAAA_LEN];
 		ret = _dns_decode_AAAA(context, addr);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode AAAA failed, %s", domain);
 			return -1;
 		}
 
 		ret = dns_add_AAAA(packet, type, domain, ttl, addr);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "add AAAA failed, %s", domain);
 			return -1;
 		}
 	} break;
@@ -944,6 +969,8 @@ int _dns_decode_an(struct dns_context *context, dns_rr_type type)
 	}
 
 	if (context->ptr - start != rr_len) {
+		tlog(TLOG_ERROR, "length mitchmatch , %s, %d:%d", domain, 
+			context->ptr - start, rr_len);
 		return -1;
 	}
 
@@ -1014,6 +1041,7 @@ int _dns_decode_body(struct dns_context *context)
 	for (i = 0; i < head->qdcount; i++) {
 		ret = _dns_decode_qd(context);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode qd failed.");
 			return -1;
 		}
 		head->qdcount--;
@@ -1022,6 +1050,7 @@ int _dns_decode_body(struct dns_context *context)
 	for (i = 0; i < head->ancount; i++) {
 		ret = _dns_decode_an(context, DNS_RRS_AN);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode an failed.");
 			return -1;
 		}
 		head->ancount--;
@@ -1030,6 +1059,7 @@ int _dns_decode_body(struct dns_context *context)
 	for (i = 0; i < head->nscount; i++) {
 		ret = _dns_decode_an(context, DNS_RRS_NS);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode ns failed.");
 			return -1;
 		}
 		head->nscount--;
@@ -1038,6 +1068,7 @@ int _dns_decode_body(struct dns_context *context)
 	for (i = 0; i < head->nrcount; i++) {
 		ret = _dns_decode_an(context, DNS_RRS_NR);
 		if (ret < 0) {
+			tlog(TLOG_ERROR, "decode nr failed.");
 			return -1;
 		}
 		head->nrcount--;
@@ -1119,6 +1150,7 @@ int dns_decode(struct dns_packet *packet, int maxsize, unsigned char *data, int
 
 	ret = _dns_decode_body(&context);
 	if (ret < 0) {
+		tlog(TLOG_ERROR, "decode body failed.\n");
 		return -1;
 	}
 
diff --git a/dns.h b/dns.h
index b5c62ab..23adf9a 100644
--- a/dns.h
+++ b/dns.h
@@ -9,7 +9,7 @@
 #define DNS_RR_A_LEN 4
 #define DNS_RR_AAAA_LEN 16
 #define DNS_MAX_CNAME_LEN 256
-#define DNS_IN_PACKSIZE 512
+#define DNS_IN_PACKSIZE (512 * 2)
 #define DNS_PACKSIZE (512 * 4)
 
 typedef enum dns_rr_type {
diff --git a/dns_client.c b/dns_client.c
index 2be9c8b..446f209 100644
--- a/dns_client.c
+++ b/dns_client.c
@@ -40,6 +40,11 @@
 #include <sys/socket.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <sys/types.h>
+       #include <sys/stat.h>
+       #include <fcntl.h>
+
+
 
 #define DNS_MAX_HOSTNAME 256
 
@@ -378,12 +383,13 @@ static int _dns_client_process_answer(char *domain, struct dns_packet *packet)
 	struct dns_query_struct *query;
 	int ttl;
 	char name[DNS_MAX_CNAME_LEN];
+	char alias[DNS_MAX_CNAME_LEN] = {0};
+	char ip[DNS_MAX_CNAME_LEN] = {0};
 	int rr_count;
 	int i = 0;
 	int j = 0;
 	struct dns_rrs *rrs = NULL;
 	int ret = -1;
-	int A_num = 0;
 
 	query = _dns_client_get_request(packet->head.id, domain);
 	if (query == NULL) {
@@ -398,12 +404,14 @@ static int _dns_client_process_answer(char *domain, struct dns_packet *packet)
 				unsigned char addr[4];
 				dns_get_A(rrs, name, DNS_MAX_CNAME_LEN, &ttl, addr);
 				printf("%s %d : %d.%d.%d.%d\n", name, ttl, addr[0], addr[1], addr[2], addr[3]);
-				sprintf(name, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
-				_dns_client_query_get(query);
-				if (fast_ping_start(name, 1, 700, dns_client_ping_result, query) == NULL) {
-					_dns_client_query_release(query);
+				sprintf(ip, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
+
+				if (strncmp(name, domain, DNS_MAX_CNAME_LEN) == 0 || strncmp(alias, name, DNS_MAX_CNAME_LEN) == 0) {
+					_dns_client_query_get(query);
+					if (fast_ping_start(ip, 1, 700, dns_client_ping_result, query) == NULL) {
+						_dns_client_query_release(query);
+					}
 				}
-				A_num++;
 			} break;
 			case DNS_T_AAAA: {
 				unsigned char addr[16];
@@ -424,6 +432,7 @@ static int _dns_client_process_answer(char *domain, struct dns_packet *packet)
 				char cname[128];
 				dns_get_CNAME(rrs, name, 128, &ttl, cname, 128);
 				printf("%s %d : %s\n", name, ttl, cname);
+				strncpy(alias, cname, DNS_MAX_CNAME_LEN);
 			} break;
 			default:
 				break;
@@ -431,10 +440,12 @@ static int _dns_client_process_answer(char *domain, struct dns_packet *packet)
 		}
 	}
 
+	pthread_mutex_lock(&client.server_list_lock);
 	query->dns_request_sent--;
-	if (query->dns_request_sent <= 0) {
+	if (query->dns_request_sent < 0) {
 		_dns_client_query_release(query);
 	}
+	pthread_mutex_unlock(&client.server_list_lock);
 
 	return ret;
 }
@@ -451,9 +462,14 @@ static int _dns_client_recv(unsigned char *inpacket, int inpacket_len, struct so
 	unsigned char packet_buff[DNS_PACKSIZE];
 	struct dns_packet *packet = (struct dns_packet *)packet_buff;
 
+	packet->head.tc = 0;
 	len = dns_decode(packet, DNS_PACKSIZE, inpacket, inpacket_len);
 	if (len != 0) {
-		printf("decode failed, packet len = %d\n", inpacket_len);
+		tlog(TLOG_ERROR, "decode failed, packet len = %d, tc=%d, %d\n", inpacket_len, 
+			packet->head.tc, packet->head.id);
+				int fd = open("dns.bin", O_CREAT | O_TRUNC | O_RDWR);
+		write(fd, inpacket, inpacket_len);
+		close(fd);
 		return -1;
 	}
 
@@ -462,8 +478,9 @@ static int _dns_client_recv(unsigned char *inpacket, int inpacket_len, struct so
 		return -1;
 	}
 
-	printf("qdcount = %d, ancount = %d, nscount = %d, nrcount = %d, len = %d, id = %d\n", packet->head.qdcount, packet->head.ancount, packet->head.nscount,
-		   packet->head.nrcount, inpacket_len, packet->head.id);
+	printf("qdcount = %d, ancount = %d, nscount = %d, nrcount = %d, len = %d, id = %d, rd = %d, ra = %d, rcode = %d\n", packet->head.qdcount, packet->head.ancount, packet->head.nscount,
+		   packet->head.nrcount, inpacket_len, packet->head.id, packet->head.rd, packet->head.ra,
+		   packet->head.rcode);
 
 	rrs = dns_get_rrs_start(packet, DNS_RRS_QD, &rr_count);
 	for (i = 0; i < rr_count && rrs; i++, rrs = dns_get_rrs_next(packet, rrs)) {
@@ -471,6 +488,12 @@ static int _dns_client_recv(unsigned char *inpacket, int inpacket_len, struct so
 		printf("domain: %s qtype: %d  qclass: %d\n", name, qtype, qclass);
 	}
 
+	if (packet->head.rcode != DNS_RC_NOERROR) {
+		tlog(TLOG_ERROR, "inquery failed, %s, rcode = %d\n", name, packet->head.rcode);
+		//TODO set response to dns_server.c
+		return -1;
+	}
+
 	return _dns_client_process_answer(name, packet);
 }
 
@@ -480,6 +503,7 @@ static int _dns_client_process(struct dns_query_struct *dns_query, unsigned long
 	unsigned char inpacket[DNS_IN_PACKSIZE];
 	struct sockaddr_storage from;
 	socklen_t from_len = sizeof(from);
+	char from_host[DNS_MAX_CNAME_LEN];
 
 	len = recvfrom(client.udp, inpacket, sizeof(inpacket), 0, (struct sockaddr *)&from, (socklen_t *)&from_len);
 	if (len < 0) {
@@ -487,6 +511,8 @@ static int _dns_client_process(struct dns_query_struct *dns_query, unsigned long
 		return -1;
 	}
 
+	tlog(TLOG_INFO, "recv from %s", gethost_by_addr(from_host, (struct sockaddr *)&from, from_len));
+
 	return _dns_client_recv(inpacket, len, &from, from_len);
 }
 
@@ -625,6 +651,8 @@ int dns_client_query(char *domain, dns_client_callback callback, void *user_ptr)
 		goto errout_del_list;
 	}
 
+	tlog(TLOG_ERROR, "send request %s, id %d\n", domain, query->sid);
+
 	key = hash_string(domain);
 	key = jhash(&query->sid, sizeof(query->sid), key);
 	pthread_mutex_lock(&client.domain_map_lock);
@@ -719,6 +747,28 @@ errout:
 	return -1;
 }
 
+void dns_debug(void)
+{
+	char data[1024];
+	int len;
+	char buff[4096];
+
+	int fd = open("dns.bin", O_RDWR);
+	if (fd < 0) {
+		return;
+	}
+	len = read(fd, data, 1024);
+	close(fd);
+	if (len < 0) {
+		return;
+	}
+
+	struct dns_packet *packet = buff;
+	if (dns_decode(packet, 4096, data, len) != 0) {
+		printf("decode failed.\n");
+	}
+}
+
 int dns_client_init()
 {
 	pthread_attr_t attr;
@@ -726,7 +776,10 @@ int dns_client_init()
 	int ret;
 	int fd = 1;
 
-	if (client.epoll_fd > 0) {
+	//dns_debug();
+
+	if (client.epoll_fd > 0)
+	{
 		return -1;
 	}
 
diff --git a/dns_server.c b/dns_server.c
index 422bd23..90c0383 100644
--- a/dns_server.c
+++ b/dns_server.c
@@ -58,6 +58,7 @@ struct dns_request {
 	atomic_t refcnt;
 	struct hlist_node map;
 	char domain[DNS_MAX_CNAME_LEN];
+	char alias[DNS_MAX_CNAME_LEN];
 	unsigned short qtype;
 	unsigned short id;
 	unsigned short ss_family;
@@ -169,6 +170,7 @@ static int _dns_add_rrs(struct dns_packet *packet, struct dns_request *request)
 	default:
 		break;
 	}
+
 	return ret;
 }
 
@@ -226,7 +228,8 @@ static int dns_server_resolve_callback(char *domain, struct dns_result *result,
 	}
 
 	memcpy(request->ipv4_addr, result->addr_ipv4, 4);
-	//memcpy(request->ipv6_addr, result->addr_ipv6, 16);
+	strncpy(request->alias, result->alias, DNS_MAX_CNAME_LEN);
+	// memcpy(request->ipv6_addr, result->addr_ipv6, 16);
 	request->qtype = DNS_T_A;
 
 	printf("----------------%s--%d.%d.%d.%d-\n", domain, 
diff --git a/fast_ping.c b/fast_ping.c
index e813bec..42d1ff4 100755
--- a/fast_ping.c
+++ b/fast_ping.c
@@ -559,15 +559,18 @@ static struct fast_ping_packet *_fast_ping_icmp6_packet(struct ping_host_struct
 	struct icmp6_hdr *icmp6 = &packet->icmp6;
 
 	if (icmp6->icmp6_type != ICMP6_ECHO_REPLY) {
+		tlog(TLOG_ERROR, "icmp6 type faild, %d:%d", icmp6->icmp6_type, ICMP6_ECHO_REPLY);
 		return NULL;
 	}
 
 	icmp_len = data_len;
 	if (icmp_len < 16) {
+		tlog(TLOG_ERROR, "length is invalid, %d", icmp_len);
 		return NULL;
 	}
 
 	if (icmp6->icmp6_id != ping.ident) {
+		tlog(TLOG_ERROR, "ident failed, %d:%d", icmp6->icmp6_id, ping.ident);
 		return NULL;
 	}
 
@@ -583,6 +586,7 @@ static struct fast_ping_packet *_fast_ping_icmp_packet(struct ping_host_struct *
 	int icmp_len;
 
 	if (ip->ip_p != IPPROTO_ICMP) {
+		tlog(TLOG_ERROR, "ip type faild, %d:%d", ip->ip_p, IPPROTO_ICMP);
 		return NULL;
 	}
 
@@ -592,14 +596,17 @@ static struct fast_ping_packet *_fast_ping_icmp_packet(struct ping_host_struct *
 	icmp_len = data_len - hlen;
 
 	if (icmp_len < 16) {
+		tlog(TLOG_ERROR, "length is invalid, %d", icmp_len);
 		return NULL;
 	}
 
 	if (icmp->icmp_type != ICMP_ECHOREPLY) {
+		tlog(TLOG_ERROR, "icmp type faild, %d:%d", icmp->icmp_type, ICMP_ECHOREPLY);
 		return NULL;
 	}
 
 	if (icmp->icmp_id != ping.ident) {
+		tlog(TLOG_ERROR, "ident failed, %d:%d", icmp->icmp_id, ping.ident);
 		return NULL;
 	}
 
@@ -621,6 +628,7 @@ struct fast_ping_packet *_fast_ping_recv_packet(struct ping_host_struct *ping_ho
 			goto errout;
 		}
 	} else {
+		tlog(TLOG_ERROR, "ping host type is invalid, %d", ping_host->type);
 		goto errout;
 	}
 
diff --git a/smartdns.c b/smartdns.c
index cb2c199..f2363e2 100755
--- a/smartdns.c
+++ b/smartdns.c
@@ -35,6 +35,8 @@ int smartdns_init()
 		goto errout;
 	}
 
+	tlog_setlogscreen(1);
+
 	ret = fast_ping_init();
     if (ret != 0) {
         fprintf(stderr, "start ping failed.\n");
@@ -53,10 +55,11 @@ int smartdns_init()
         goto errout;
     }
 
-	dns_add_server("192.168.1.1", 53, DNS_SERVER_UDP);
+	//dns_add_server("192.168.1.1", 53, DNS_SERVER_UDP);
     dns_add_server("114.114.114.114", 53, DNS_SERVER_UDP);
 	dns_add_server("123.207.137.88", 53, DNS_SERVER_UDP);
-	fast_ping_start("192.168.1.1", 10, 1000, 0, 0);
+	dns_add_server("193.112.15.186", 53, DNS_SERVER_UDP);
+	//dns_add_server("202.141.178.13", 5353, DNS_SERVER_UDP);
 	return 0;
 errout: