Windows Server 2003 DNS 新增功能 林寶森

2003 DNS 的新增功能 Stub Zone Conditional Forwarding Local Subnet Priority Round-robin Rotation Disabling Recursion Store DNS Data in Application Partition of Active Directory

Fully Qualified Domain Name FQDN = Host Name + Domain Name Example: – www is Host Name – abc.com.tw is Domain Name

What is a DNS Zone? abc.com.tw west south support sales training north

What Are DNS Zone Types? ZonesDescription Primary Read/write copy of a DNS database Secondary Read-only copy of a DNS database Stub Copy of a zone containing limited records Read/Write Read-Only Copy of limited records

Multiple Domain 的名稱解析 Windows 2000 Server – 公司自行成立 DNS Root Server ，所有的 DNS Server 皆修改 Root Hints 指向公司的 Root Server 。 –DNS Server 互相做對方的 Secondary –DNS Server 互相 Forwarding Windows Server 2003 –Stub Zone –Conditional Forwarding

Server Default Preferences PropertyDefault setting Disable recursionOff BIND secondariesOn Fail on load if bad zone dataOff Enable round robinOn Enable netmask orderingOn Secure cache against pollutionOn Name checkingMultibyte (UTF8) Load zone data on startupFrom Active Directory and registry Enable automatic scavengingOff

DNS Server Roles RoleSituation Caching-only servers A remote office has a limited amount of available bandwidth Non-recursive servers You have Internet-facing DNS that are authoritative for one or more zones Forward-only servers You want to manage the DNS traffic between your network and the Internet Conditional forwarders You want DNS clients in separate networks to resolve each others’ names without having to query the DNS server on the Internet

Using Caching-Only Servers Perform name resolution on behalf of client computers and cache the results Can be used to reduce DNS-related traffic across a WAN Caching-Only DNS Server Client Remote Office DNS Server Corporate Headquarters Slow WAN Link

NSLOOKUP 指令 set OPTION- set an option [no]recurse- ask for recursive answer to query domain=NAME- set default domain name to NAME type=X- set query type (ex. A, ANY, CNAME, MX, NS) querytype=X- same as type [no]msxfr- use MS fast zone transfer ixfrver=X- current version to use in IXFR transfer request server NAME- set default server to NAME ls [opt] DOMAIN- list addresses in DOMAIN -a- list canonical names and aliases -d- list all records -t TYPE- list records of the given type (e.g. A, CNAME, MX, etc.)

用 NSLOOKUP 解決下列問題 使用者抱怨有些網站無法連結 廠商或客戶連不上公司網站 廠商或客戶的電子郵件寄不過去 廠商或客戶的電子郵件收不到 強迫別人的 DNS 學習的方式

電子郵件無法傳遞時 自家的 DNS Server 是否能夠查到對方的記錄 ? 自家的 Mail Server 是否能連線對方的 Server? 兩邊的 Mail Server 頻寬是否足夠 ? 對方是否有對 Mail Server 做反向查詢驗證 ? 對方是否有設 Block List? 收件者是否存在 ? 是否超過收件者人數上限 ? 郵件是否超過可接受之大小 ? 是否中毒 ? 啟動 Mail Server 的 Log 功能以檢查詳細過程

改善收信的狀況 External DNS 委外 架設多台 Mail Server 及 Mail Relay MX10mail1.nwtraders.msft MX10mail2.nwtraders.msft MX20mail.seed.net.tw MX30mail.uu.net 租用 ETRN 服務 租用 Mailbox 服務