OpenWrt之DNS设置

OpenWrt之DNS设置

0.前言

本文不涉及smartdns、adguardhome、dns防污染等内容,只介绍DNS的设置


1.WAN口

wan.png
wan2.png

保存&应用后 客户机发出dns解析请求后路由器用上面的dns回应


2.Lan口

进入openwrt的luci页面。在 网络>网卡>LAN 选择编辑

LANLAN

NUEXINI.LAN2

保存&应用后,路由器自身的dns解析请求 会使用 上面设置的DNS 来回应


3.LAN口DHCP选项

进入openwrt的luci页面。在 网络>网卡>LAN 选择编辑

NueXini

在 DHCP选项下 填入

6,223.5.5.5,119.29.29.29

效果如下:

DNS

该设置会修改连接到路由器LAN的DNS(类似于自定义电脑的DNS)

DNS


4.DHCP/DNS

dhcpdns.png


5.总结

电脑DNS(LAN) > DHCP的DNS > WAN口DNS

1.最常用的DNS设置方式。可以由DHCP请求获得,或自行设置。在静态IP的情况下,必须设置,否则无法查询外面的主机

2.如果路由器用于桥接方式,并且使用静态IP时,无法用DHCP请求的方式得到DNS,这是该选项的主要用途。其他场合下,则会忽略由DHCP服务器的DNS设置,改用这个设置。

3.如果该机器是子网的DHCP服务器,用于设置DHCP客户端的DNS。如果留空,默认则用自身的IP。通常客户端看到的DNS是这个(手机,电脑等)

4.如果自己是子网的DNS服务器,用于设置转发服务器。如果不设置,则用上游DNS(由1或2)服务器

当第2、3、4项不设置时,默认使用1的DNS解析


参考(Thanks)

https://www.iana.org/assignments/bootp-dhcp-parameters/bootp-dhcp-parameters.xhtml#options

https://blog.csdn.net/weixin_41632560/article/details/89448612

https://www.right.com.cn/forum/thread-4059633-1-1.html


附录.DHCP OPTION

以下是部分DHCP OPTION参照表

DHCP OPTION Meaing
0 None
1 设置子网掩码
2 "Time Offset in Seconds from UTC
3 设置网关
4 N/4 Timeserver addresses
5 N/4 IEN-116 Server addresses
6 设置DNS服务器
7 N/4 Logging Server addresses
8 N/4 Quotes Server addresses
9 N/4 Printer Server addresses
10 N/4 Impress Server addresses
11 N/4 RLP Server addresses
12 设置域名选项。
13 Size of boot file in 512 byte chunks
14 Client to dump and name the file to dump it to
15 设置域名后缀选项。
16 Swap Server address
17 Path name for root disk
18 Path name for more BOOTP info
19 Enable/Disable IP Forwarding
20 Enable/Disable Source Routing
21 Routing Policy Filters
22 Max Datagram Reassembly Size
23 Default IP Time to Live
24 Path MTU Aging Timeout
25 Path MTU Plateau Table
26 Interface MTU Size
27 All Subnets are Local
28 Broadcast Address
29 Perform Mask Discovery
30 Provide Mask to Others
31 Perform Router Discovery
32 Router Solicitation Address
33 设置静态路由选项。该选项中包含一组有分类静态路由(即目的地址的掩码固定为自然掩码,不能划分子网),客户端收到该选项后,将在路由表中添加这些静态路由。如果存在Option121,则忽略该选项。
34 Trailer Encapsulation
35 ARP Cache Timeout
36 Ethernet Encapsulation
37 Default TCP Time to Live
38 TCP Keepalive Interval
39 TCP Keepalive Garbage
40 NIS Domain Name
41 NIS Server Addresses
42 NTP Server Addresses
43 Vendor Specific Information
44 设置NetBios服务器选项。
45 NETBIOS Datagram Distribution
46 设置NetBios节点类型选项。
47 NETBIOS Scope
48 X Window Font Server
49 X Window Display Manager
50 设置请求IP选项。
51 设置IP地址租约时间选项。
52 设置Option附加选项。
53 设置DHCP消息类型。
54 设置服务器标识。
55 设置请求参数列表选项。客户端利用该选项指明需要从服务器获取哪些网络配置参数。该选项内容为客户端请求的参数对应的选项值。
56 DHCP Error Message
57 DHCP Maximum Message Size
58 设置续约T1时间,一般是租期时间的50%。
59 设置续约T2时间。一般是租期时间的87.5%。
60 设置厂商分类信息选项,用于标识DHCP客户端的类型和配置。
61 设置客户端标识选项。
62 NetWare/IP Domain Name
63 NetWare/IP sub Options
64 NIS+ v3 Client Domain Name
65 NIS+ v3 Server Addresses
66 设置TFTP服务器名选项,用来指定为客户端分配的TFTP服务器的域名。
67 设置启动文件名选项,用来指定为客户端分配的启动文件名。
68 Home Agent Addresses
69 Simple Mail Server Addresses
70 Post Office Server Addresses
71 Network News Server Addresses
72 WWW Server Addresses
73 Finger Server Addresses
74 Chat Server Addresses
75 StreetTalk Server Addresses
76 ST Directory Assist. Addresses
77 设置用户类型标识。
78 directory agent information
79 service location agent scope
80 Rapid Commit
81 Fully Qualified Domain Name
82 Relay Agent Information
83 Internet Storage Name Service
85 Novell Directory Services
86 Novell Directory Services
87 Novell Directory Services
90 Authentication
93 Client System Architecture
94 Client Network Device Interface
95 Lightweight Directory Access Protocol
97 UUID/GUID-based Client Identifier
98 Open Group's User Authentication
100 IEEE 1003.1 TZ String
101 Reference to the TZ Database
108 Number of seconds that DHCPv4 should be disabled
109 DHCPv4 over DHCPv6 Softwire Source Address Option
112 NetInfo Parent Server Address
113 NetInfo Parent Server Tag
114 DHCP Captive-Portal
116 DHCP Auto-Configuration
117 Name Service Search
118 Subnet Selection Option
119 DNS domain search list
120 SIP Servers DHCP Option
121 设置无分类路由选项。该选项中包含一组无分类静态路由(即目的地址的掩码为任意值,可以通过掩码来划分子网),客户端收到该选项后,将在路由表中添加这些静态路由。
122 CableLabs Client Configuration
123 GeoConf Option
124 Vendor-Identifying Vendor Class
125 Vendor-Identifying Vendor-Specific Information
138 CAPWAP Access Controller addresses
139 a series of suboptions
140 a series of suboptions
141 List of domain names to search for SIP User Agent Configuration
142 ANDSF IPv4 Address Option for DHCPv4
143 This option provides a list of URIs for SZTP bootstrap servers
144 Geospatial Location with Uncertainty
145 Forcerenew Nonce Capable
146 Information for selecting RDNSS
147 The name of the peer DOTS agent.
148 N/4 IPv4 addresses of peer DOTS agent(s).
150 设置TFTP服务器地址选项,指定为客户端分配的TFTP服务器的地址。
151 Status code and optional N byte text message describing status.
152 "Absolute time (seconds since Jan 1, 1970) message was sent."
153 Number of seconds in the past when client entered current state.
154 "Absolute time (seconds since Jan 1, 1970) for beginning of query."
155 "Absolute time (seconds since Jan 1, 1970) for end of query."
156 State of IP address.
157 Indicates information came from local or remote server.
158 Includes one or multiple lists of PCP server IP addresses; each list is treated as a separate PCP server.
159 This option is used to configure a set of ports bound to a shared IPv4 address.
160 Previously assigned by [RFC7710]; known to also be used by Polycom.
161 Manufacturer Usage Descriptions
posted @ 2021-12-17 17:39  虐心i  阅读(29529)  评论(0编辑  收藏  举报