diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5d0e494e5e..1f4d00afe4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 ## 更新日志
-- v1.4.6(2023-06-23)
+- v1.4.7(2023-06-23)
+    - 优化 获取证书支持：IP证书、多域名证书、通配符证书
+    - 优化 移除未使用的域名信息缓存表`cache_domain_info`
+
+- v1.4.6(2023-06-22)
     - 新增 通知方式增加备注字段
     - 新增 通知方式新增钉钉、飞书渠道
 
diff --git a/domain_admin/api/domain_api.py b/domain_admin/api/domain_api.py
index 988df678f7..1bd37864b7 100644
--- a/domain_admin/api/domain_api.py
+++ b/domain_admin/api/domain_api.py
@@ -50,20 +50,22 @@ def add_domain():
     domain_service.update_domain_row(row)
 
     # 顺带添加到域名监测列表
-    first_domain_info_row = DomainInfoModel.select(
-        DomainInfoModel.id
-    ).where(
-        DomainInfoModel.domain == data['root_domain'],
-        DomainInfoModel.user_id == current_user_id
-    ).first()
-
-    if not first_domain_info_row:
-        domain_info_service.add_domain_info(
-            domain=domain_util.get_root_domain(domain),
-            comment=alias,
-            group_id=group_id,
-            user_id=current_user_id,
-        )
+    if not domain_util.is_ipv4(domain):
+
+        first_domain_info_row = DomainInfoModel.select(
+            DomainInfoModel.id
+        ).where(
+            DomainInfoModel.domain == data['root_domain'],
+            DomainInfoModel.user_id == current_user_id
+        ).first()
+
+        if not first_domain_info_row:
+            domain_info_service.add_domain_info(
+                domain=domain_util.get_root_domain(domain),
+                comment=alias,
+                group_id=group_id,
+                user_id=current_user_id,
+            )
 
     return {'id': row.id}
 
diff --git a/domain_admin/log.py b/domain_admin/log.py
index 7d7bb93328..c2dcc09d8d 100644
--- a/domain_admin/log.py
+++ b/domain_admin/log.py
@@ -7,7 +7,11 @@
 logger = logging.getLogger('domain-admin')
 
 # 单个日志文件最大为1M
-handler = RotatingFileHandler(resolve_log_file("domain-admin.log"), maxBytes=1024 * 1024 * 1, encoding='utf-8')
+handler = RotatingFileHandler(
+    filename=resolve_log_file("domain-admin.log"),
+    maxBytes=1024 * 1024 * 1,
+    encoding='utf-8'
+)
 
 # 设置日志格式
 formatter = logging.Formatter(
diff --git a/domain_admin/model/cache_domain_info_model.py b/domain_admin/model/cache_domain_info_model.py
deleted file mode 100644
index 44fb174916..0000000000
--- a/domain_admin/model/cache_domain_info_model.py
+++ /dev/null
@@ -1,53 +0,0 @@
-# -*- coding: utf-8 -*-
-from datetime import datetime
-
-from peewee import CharField, IntegerField, DateTimeField, AutoField
-
-from domain_admin.model.base_model import BaseModel
-from domain_admin.utils import time_util
-
-
-class CacheDomainInfoModel(BaseModel):
-    """
-    域名信息缓存表
-    @since 1.2.12
-    @Deprecated @since 1.4.0
-    """
-    id = AutoField(primary_key=True)
-
-    # 域名
-    domain = CharField(unique=True)
-
-    # 域名注册时间
-    domain_start_time = DateTimeField(default=None, null=True)
-
-    # 域名过期时间
-    domain_expire_time = DateTimeField(default=None, null=True)
-
-    # 缓存过期时间
-    expire_time = DateTimeField(default=None, null=True)
-
-    # 创建时间
-    create_time = DateTimeField(default=datetime.now)
-
-    # 更新时间
-    update_time = DateTimeField(default=datetime.now)
-
-    class Meta:
-        table_name = 'cache_domain_info'
-
-    @property
-    def is_expired(self) -> [bool, None]:
-        """
-        过期时间
-        :return:
-        """
-        if self.expire_time:
-            return (self.expire_time - datetime.now()).seconds <= 0
-        else:
-            return None
-
-    @property
-    def domain_expire_days(self) -> int:
-        """域名过期天数"""
-        return time_util.get_diff_days(datetime.now(), self.domain_expire_time)
diff --git a/domain_admin/model/database.py b/domain_admin/model/database.py
index a5a8204f66..a74d218730 100644
--- a/domain_admin/model/database.py
+++ b/domain_admin/model/database.py
@@ -26,7 +26,7 @@
     (group_model.GroupModel, None),
     (domain_model.DomainModel, None),
     (notify_model.NotifyModel, None),
-    (cache_domain_info_model.CacheDomainInfoModel, None),
+    # (cache_domain_info_model.CacheDomainInfoModel, None),
     (address_model.AddressModel, None),
     (domain_info_model.DomainInfoModel, None),
 ]
diff --git a/domain_admin/service/cache_domain_info_service.py b/domain_admin/service/cache_domain_info_service.py
deleted file mode 100644
index 59f00c7fdb..0000000000
--- a/domain_admin/service/cache_domain_info_service.py
+++ /dev/null
@@ -1,46 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
-@File    : cache_domain_info_service.py
-@Date    : 2023-04-22
-"""
-from datetime import datetime, timedelta
-
-from domain_admin.model.cache_domain_info_model import CacheDomainInfoModel
-from domain_admin.utils import domain_util
-from domain_admin.utils.whois_util import whois_util
-
-
-def get_domain_info(domain: str) -> CacheDomainInfoModel:
-    """
-    加一个缓存获取域名信息
-    :param domain:
-    :return:
-    """
-    root_domain = domain_util.get_root_domain(domain)
-
-    row = CacheDomainInfoModel.select().where(
-        CacheDomainInfoModel.domain == root_domain
-    ).get_or_none()
-
-    # 不存在或者已过期，重新获取
-    if not row or row.is_expired is True:
-        domain_whois = whois_util.get_domain_info(root_domain)
-
-        if domain_whois is None:
-            raise Exception("域名信息获取失败")
-
-        data = {
-            "domain": root_domain,
-            "domain_start_time": domain_whois['start_time'],
-            "domain_expire_time": domain_whois['expire_time'],
-            "expire_time": datetime.now() - timedelta(minutes=3)
-        }
-
-        if not row:
-            row = CacheDomainInfoModel.create(**data)
-        else:
-            CacheDomainInfoModel.update(data).where(
-                CacheDomainInfoModel.id == row.id
-            ).execute()
-
-    return row
diff --git a/domain_admin/service/domain_info_service.py b/domain_admin/service/domain_info_service.py
index 908ea5301c..a73f3d1bbc 100644
--- a/domain_admin/service/domain_info_service.py
+++ b/domain_admin/service/domain_info_service.py
@@ -2,6 +2,8 @@
 """
 domain_info_service.py
 """
+import random
+import time
 import traceback
 from datetime import datetime
 from typing import List
@@ -62,7 +64,12 @@ def update_domain_info_row(row: DomainInfoModel) -> [str, None]:
     try:
         domain_whois = whois_util.get_domain_info(row.domain)
     except Exception as e:
-        pass
+        # 增加容错
+        try:
+            time.sleep(3)
+            domain_whois = whois_util.get_domain_info(row.domain)
+        except Exception as e:
+            pass
 
     update_row = DomainInfoModel()
 
diff --git a/domain_admin/service/domain_service.py b/domain_admin/service/domain_service.py
index 96159422f5..71d88dedf7 100644
--- a/domain_admin/service/domain_service.py
+++ b/domain_admin/service/domain_service.py
@@ -2,7 +2,6 @@
 """
 domain_service.py
 """
-import time
 import traceback
 import warnings
 from datetime import datetime
@@ -15,84 +14,17 @@
 from domain_admin.model.address_model import AddressModel
 from domain_admin.model.domain_model import DomainModel
 from domain_admin.model.group_model import GroupModel
-from domain_admin.model.log_scheduler_model import LogSchedulerModel
 from domain_admin.model.user_model import UserModel
-from domain_admin.service import email_service, render_service, global_data_service, cache_domain_info_service
+from domain_admin.service import email_service, render_service
 from domain_admin.service import file_service
 from domain_admin.service import notify_service
 from domain_admin.service import system_service
-from domain_admin.utils import datetime_util, cert_util, whois_util, file_util, time_util
+from domain_admin.utils import datetime_util, cert_util, whois_util
 from domain_admin.utils import domain_util
-from domain_admin.utils.cert_util import cert_common, cert_socket_v2
+from domain_admin.utils.cert_util import cert_common, cert_socket_v2, cert_openssl_v2
 from domain_admin.utils.flask_ext.app_exception import AppException, ForbiddenAppException
 
 
-def update_domain_info(domain_row: DomainModel):
-    """
-    更新域名信息
-    :param row:
-    :return:
-    """
-    # logger.info("%s", model_to_dict(domain_row))
-
-    # 获取域名信息
-    domain_info = None
-
-    err = ''
-
-    try:
-        domain_info = cache_domain_info_service.get_domain_info(domain_row.domain)
-    except Exception as e:
-        err = e.__str__()
-        pass
-
-    update_data = {
-        'domain_start_time': None,
-        "domain_expire_time": None,
-        'domain_expire_days': 0,
-    }
-
-    if domain_info:
-        update_data = {
-            'domain_start_time': domain_info.domain_start_time,
-            "domain_expire_time": domain_info.domain_expire_time,
-            'domain_expire_days': domain_info.domain_expire_days,
-        }
-
-    DomainModel.update(
-        **update_data,
-        domain_check_time=datetime_util.get_datetime(),
-        update_time=datetime_util.get_datetime(),
-    ).where(
-        DomainModel.id == domain_row.id
-    ).execute()
-
-    return err
-
-
-def update_ip_info(row: DomainModel):
-    """
-    更新ip信息
-    :param row:
-    :return:
-    """
-    # 获取ip地址
-    domain_ip = ''
-
-    try:
-        domain_ip = cert_common.get_domain_ip(row.domain)
-    except Exception as e:
-        pass
-
-    DomainModel.update(
-        ip=domain_ip,
-        ip_check_time=datetime_util.get_datetime(),
-        update_time=datetime_util.get_datetime(),
-    ).where(
-        DomainModel.id == row.id
-    ).execute()
-
-
 def update_domain_host_list(domain_row: DomainModel):
     """
     更新ip信息
@@ -153,7 +85,7 @@ def update_address_row_info(address_row, domain_row):
 
     err = ''
     try:
-        cert_info = cert_socket_v2.get_ssl_cert_info(
+        cert_info = cert_openssl_v2.get_ssl_cert_by_openssl(
             domain=domain_row.domain,
             host=address_row.host,
             port=domain_row.port
@@ -543,6 +475,8 @@ def send_domain_list_email(user_id, rows: List[DomainModel]):
         to_addresses=email_list,
         content_type='html'
     )
+
+
 def check_permission_and_get_row(domain_id, user_id):
     """
     权限检查
diff --git a/domain_admin/utils/cert_util/cert_openssl_v2.py b/domain_admin/utils/cert_util/cert_openssl_v2.py
index 8660700728..d11a24c88c 100644
--- a/domain_admin/utils/cert_util/cert_openssl_v2.py
+++ b/domain_admin/utils/cert_util/cert_openssl_v2.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 """
-@File    : demo.py
+@File    : cert_openssl_v2.py
 @Date    : 2023-06-19
 """
 import socket
@@ -8,15 +8,81 @@
 
 import OpenSSL
 
-from domain_admin.utils.cert_util import cert_common
+from domain_admin.utils import domain_util, time_util
 
 
-def get_ssl_cert_by_openssl(domain: str, host: str = None, port: int = 443, timeout: int = 3):
+def get_certificate_san(x509cert):
+    """
+    获取SAN域名列表
+    ref: https://cloud.tencent.com/developer/ask/sof/141600
+    :param x509cert:
+    :return:
+    """
+    dns_names = []
+
+    ext_count = x509cert.get_extension_count()
+
+    for i in range(0, ext_count):
+        ext = x509cert.get_extension(i)
+        if 'subjectAltName' in str(ext.get_short_name()):
+            for item in str(ext).split(', '):
+
+                if item.startswith('DNS:'):
+                    key, value = item.split(':')
+                    dns_names.append(value.strip())
+
+    return dns_names
+
+
+def verify_cert(cert, domain):
+    """
+    验证证书和域名是否匹配
+    :param cert:
+    :param domain:
+    :return:
+    """
+    # 检查 颁发对象 域名（CN） 备用域名（SAN）
+    common_name = cert.get_subject().commonName
+
+    dns_names = get_certificate_san(cert)
+
+    if common_name not in dns_names:
+        dns_names.insert(0, common_name)
+
+    print(domain)
+    print(dns_names)
+
+    for dns_name in dns_names:
+        domain_checked = domain_util.verify_cert_common_name(dns_name, domain)
+        if domain_checked:
+            return True
+
+    return False
+
+
+def get_ssl_cert_by_openssl(
+        domain: str,
+        host: str = None,
+        port: int = 443,
+        timeout: int = 3):
+    """
+    不验证证书，仅验证域名
+    支持通配符
+    :param domain:
+    :param host:
+    :param port:
+    :param timeout:
+    :return:
+    """
+    # socket
     sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
     sock.settimeout(timeout)
     sock.connect((host, port))
 
+    # ssl
     ssl_context = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
+    ssl_context.verify_mode = ssl.CERT_NONE
+    ssl_context.check_hostname = False
 
     with ssl_context.wrap_socket(sock, server_hostname=domain) as wrap_socket:
         dercert = wrap_socket.getpeercert(True)
@@ -24,13 +90,13 @@ def get_ssl_cert_by_openssl(domain: str, host: str = None, port: int = 443, time
     server_cert = ssl.DER_cert_to_PEM_cert(dercert)
     cert = OpenSSL.crypto.load_certificate(OpenSSL.crypto.FILETYPE_PEM, server_cert.encode())
 
-    return {
-        'start_date': cert_common.parse_time(cert.get_notBefore().decode()),
-        'expire_date': cert_common.parse_time(cert.get_notAfter().decode()),
-    }
+    # verify
+    domain_checked = verify_cert(cert, domain)
 
+    if not domain_checked:
+        raise Exception("domain not verified")
 
-if __name__ == '__main__':
-    # get_ssl_cert_by_openssl('pgmanage.qnvip.com', '121.196.205.251')
-    # get_ssl_cert_by_openssl('cdn-image-01.kaishuleyuan.com', '101.96.145.100')
-    get_ssl_cert_by_openssl('dev.csdn.net', '120.46.209.149')
+    return {
+        'start_date': time_util.parse_time(cert.get_notBefore().decode()),
+        'expire_date': time_util.parse_time(cert.get_notAfter().decode()),
+    }
\ No newline at end of file
diff --git a/domain_admin/utils/cert_util/cert_socket_v2.py b/domain_admin/utils/cert_util/cert_socket_v2.py
index 6a50095854..3fbf83cec0 100644
--- a/domain_admin/utils/cert_util/cert_socket_v2.py
+++ b/domain_admin/utils/cert_util/cert_socket_v2.py
@@ -13,7 +13,6 @@
 
 from domain_admin.log import logger
 from domain_admin.utils import time_util
-from domain_admin.utils.cert_util import cert_common
 
 
 def get_domain_host_list(domain: str, port: int = 80) -> typing.List[str]:
@@ -71,7 +70,10 @@ def get_ssl_cert_info(domain: str, host: str = None, port: int = 443, timeout: i
     :param timeout:
     :return:
     """
-    return resolve_cert(get_ssl_cert(domain, host, port, timeout))
+    cert = get_ssl_cert(domain, host, port, timeout)
+    print(cert)
+
+    return resolve_cert(cert)
 
 
 def resolve_cert(cert: typing.Dict):
@@ -89,4 +91,7 @@ def resolve_cert(cert: typing.Dict):
 
 
 if __name__ == '__main__':
-    print(get_ssl_cert_info('dev.csdn.net', '120.46.209.149'))
+    # print(get_ssl_cert_info('www.taobao.com', '111.62.93.139'))
+    print(get_ssl_cert_info('38.60.47.102', '38.60.47.102'))
+    # print('www.baidu.com'.encode('idna')) # b'www.baidu.com'
+    # print('www.baidu.com'.encode('punycode')) # b'www.baidu.com-'
diff --git a/domain_admin/utils/domain_util.py b/domain_admin/utils/domain_util.py
index 8faaee2684..53137563d8 100644
--- a/domain_admin/utils/domain_util.py
+++ b/domain_admin/utils/domain_util.py
@@ -8,8 +8,10 @@
 from typing import NamedTuple
 
 import tldextract
+from tldextract.remote import looks_like_ip
 from tldextract.tldextract import ExtractResult
 
+from domain_admin.log import logger
 from domain_admin.utils import file_util
 from domain_admin.utils.cert_util import cert_consts
 
@@ -132,4 +134,51 @@ def get_root_domain(domain: str) -> str:
     :return:
     """
     extract_result = extract_domain(domain)
-    return '.'.join([extract_result.domain, extract_result.suffix])
+    return extract_result.registered_domain
+    # return '.'.join([extract_result.domain, extract_result.suffix])
+
+
+def is_ipv4(ip) -> bool:
+    """
+    检测一个字符串是否是ipv4地址
+    :param ip:
+    :return:
+    """
+    return looks_like_ip(ip)
+
+    # if re.match("(\d+\.){3}\d+", ip):
+    #     return True
+    # else:
+    #     return False
+
+
+def encode_hostname(hostname: str) -> str:
+    """
+    编码中文域名，英文域名原样返回
+    :param hostname: 中文域名
+    :return:
+    """
+    return hostname.encode('idna').decode('ascii')
+
+
+def verify_cert_common_name(common_name, domain):
+    """
+    验证证书
+    :param common_name:
+    :param domain:
+    :return:
+    """
+    logger.info("%s <=> %s", common_name, domain)
+
+    if '*' in common_name:
+        # 通配符 SSL 证书
+        common_name_root_domain = get_root_domain(common_name)
+        root_domain = get_root_domain(domain)
+        return common_name_root_domain == root_domain
+    else:
+        # 普通证书
+        return common_name == domain
+
+
+if __name__ == '__main__':
+    print(get_root_domain("*.juejin.cn"))
diff --git a/domain_admin/utils/whois_util/whois_util.py b/domain_admin/utils/whois_util/whois_util.py
index 32b92be6c0..c3b3d6dbcb 100644
--- a/domain_admin/utils/whois_util/whois_util.py
+++ b/domain_admin/utils/whois_util/whois_util.py
@@ -30,23 +30,29 @@ def resolve_domain(domain: str) -> str:
     :return:
     """
     # 解析出域名和顶级后缀
-    extract_result = domain_util.extract_domain(domain)
-
-    root_domain = extract_result.domain
-    suffix = extract_result.suffix
-
-    # 处理包含中文的域名
-    if text_util.has_chinese(suffix):
-        pass
-
-    elif text_util.has_chinese(root_domain):
-        chinese = text_util.extract_chinese(root_domain)
-        punycode = chinese.encode('punycode').decode()
-        root_domain = f"xn--{punycode}"
-
-    domain_and_suffix = '.'.join([root_domain, suffix])
-
-    return domain_and_suffix
+    if domain_util.is_ipv4(domain):
+        return domain
+    else:
+        root_domain = domain_util.get_root_domain(domain)
+        return domain_util.encode_hostname(root_domain)
+
+    # extract_result = domain_util.extract_domain(domain)
+    #
+    # root_domain = extract_result.domain
+    # suffix = extract_result.suffix
+    #
+    # # 处理包含中文的域名
+    # if text_util.has_chinese(suffix):
+    #     pass
+    #
+    # elif text_util.has_chinese(root_domain):
+    #     chinese = text_util.extract_chinese(root_domain)
+    #     punycode = chinese.encode('punycode').decode()
+    #     root_domain = f"xn--{punycode}"
+    #
+    # domain_and_suffix = '.'.join([root_domain, suffix])
+    #
+    # return domain_and_suffix
 
 
 def parse_time(time_str, time_format=None):
@@ -73,14 +79,18 @@ def load_whois_servers_config():
 
     config = {}
 
+    # 通用配置
     for root, server in whois_servers.items():
-        # 通用配置
         server_config = deepcopy(DEFAULT_WHOIS_CONFIG)
         server_config['whois_server'] = server
-        config[root] = server_config
+        config[domain_util.encode_hostname(root)] = server_config
+
+    # 自定义配置优先
+    for key, value in CUSTOM_WHOIS_CONFIGS.items():
+        config[domain_util.encode_hostname(key)] = value
 
-    # 合并配置自定义配置优先
-    return {**config, **CUSTOM_WHOIS_CONFIGS}
+    # 合并配置
+    return config
 
 
 def get_whois_config(domain: str) -> [str, None]:
diff --git a/tests/utils/test_cert_util.py b/tests/utils/test_cert_util.py
index 05bf009071..18109d42f5 100644
--- a/tests/utils/test_cert_util.py
+++ b/tests/utils/test_cert_util.py
@@ -7,7 +7,7 @@
 import socket
 
 from domain_admin.utils import cert_util
-from domain_admin.utils.cert_util import cert_socket_v2
+from domain_admin.utils.cert_util import cert_socket_v2, cert_openssl_v2
 
 
 def test_get_cert_info():
@@ -19,8 +19,9 @@ def test_cert_socket_v2():
     ret = cert_socket_v2.get_ssl_cert_info(
         # 'www.csdn.net',
         # '123.129.227.79',
-        'cdn-image-01.kaishuleyuan.com',
-        '101.96.145.100'
+        # '38.60.47.102',
+        # '38.60.47.102'
+        'juejin.cn', '223.111.193.232'
     )
     print(ret)
 
@@ -35,3 +36,22 @@ def test_getaddrinfo():
     ret = socket.getaddrinfo('www.baidu.com', 443, proto=socket.IPPROTO_TCP)
     for item in ret:
         print(item)
+
+
+def test_get_default_verify_paths():
+    import ssl
+    print(ssl.get_default_verify_paths())
+
+
+def test_get_ssl_cert_by_openssl():
+    lst = [
+        # ('cdn-image-01.kaishuleyuan.com', '101.96.145.100'),
+        # ('www.tmall.com', '111.13.104.112'),
+        # ('juejin.cn', '223.111.193.232'),
+        # ('dev.csdn.net', '120.46.209.149'),
+        # ('38.60.47.102', '38.60.47.102'),
+        ('pgmanage.qnvip.com', '121.196.205.251'),
+    ]
+
+    for domain, host in lst:
+        cert_openssl_v2.get_ssl_cert_by_openssl(domain, host)
diff --git a/tests/utils/test_domain_util.py b/tests/utils/test_domain_util.py
index 9fc17b5783..15101bf261 100644
--- a/tests/utils/test_domain_util.py
+++ b/tests/utils/test_domain_util.py
@@ -43,3 +43,23 @@ def test_parse_domain_from_txt_file():
         lst = domain_util.parse_domain_from_txt_file(domain_filename)
         for index, row in enumerate(lst):
             assert row['domain'] == expect_domains[index]
+
+
+def test_is_ipv4():
+    assert domain_util.is_ipv4('38.60.47.102') == True
+    assert domain_util.is_ipv4('www.baidu.com') == False
+
+
+def test_get_root_domain():
+    print(domain_util.get_root_domain('38.60.47.102'))
+    print(domain_util.get_root_domain('www.baidu.com'))
+    print(domain_util.get_root_domain('www.baidu.com.cn'))
+    # assert domain_util.get_root_domain('www.baidu.com') == True
+
+
+def test_encode_hostname():
+    assert domain_util.encode_hostname('www.baidu.com') == 'www.baidu.com'
+
+    assert domain_util.encode_hostname('baidu.中国') == 'baidu.xn--fiqs8s'
+
+    assert domain_util.encode_hostname('百度.中国') == 'xn--wxtr44c.xn--fiqs8s'
diff --git a/tests/utils/test_whois_util.py b/tests/utils/test_whois_util.py
index e9624a55d0..6a136ef060 100644
--- a/tests/utils/test_whois_util.py
+++ b/tests/utils/test_whois_util.py
@@ -43,3 +43,9 @@ def test_get_domain_info():
     for domain in domain_list:
         # print(parse_whois_raw(get_whois_raw(domain, ROOT_SERVER)))
         print(whois_util.get_domain_info(domain))
+
+
+def test_resolve_domain():
+    assert whois_util.resolve_domain('www.baidu.com') == 'baidu.com'
+    assert whois_util.resolve_domain('www.baidu.中国') == 'baidu.xn--fiqs8s'
+    assert whois_util.resolve_domain('192.168.0.1') == '192.168.0.1'