tailieunhanh - WINDOWS 2000 TROUBLE SHOOTING TCP/I P phần 6

Nhưng nó không giải quyết được vấn đề. Khi một người sử dụng nội bộ kết nối với , một truy vấn DNS được gửi đến máy chủ DNS nội bộ, và được giải quyết đến địa chỉ IP của máy chủ tin tức nội bộ. Một người dùng kết nối đến thông qua các địa chỉ liên lạc Internet các máy chủ DNS bên ngoài tường lửa, | 344 Chapter 7 Troubleshooting Windows 2000 DNS Problems But it does solve the problem. When an internal user connects to a DNS query is sent to the internal DNS server and is resolved to the IP address of the internal news server. A user connecting to via the Internet contacts the DNS server outside the firewall and receives the IP address of the Internet-located news server. At no time do your internal resources become threatened or touched by Internet users. Figure displays a simplified network layout of this configuration. Note the two DNS servers one internal and one external. Each of the DNS servers will have different zone databases and they most definitely will not participate in zone transfer with each other. This is the most common scenario you ll encounter because most organizations already have a domain name and are wary of change. However if you are blessed enough to be working with a new network installation or an unusually flexible company the second approach is a lot easier and more flexible. Figure Network layout with same internal and external domain name. Proxy DNS is located in DMZ internal to the firewall. Proxy DNS Internet Net News DNS Net Web Firewall Net Mail Internal News External Ol Internal Internal Intern Web Mail News Servers External to the Firewall are directly exposed. Troubleshooting Windows 2000 DNS Problems Chapter 7 345 Different Intranet and Internet Domain Names The best way to go is with different domain names representing your intranet and Internet resources. In this case we could have two domain names and . The former is used for internal resources and the latter for Internet resources. The internal servers would be and . The Internet servers would be and . The DNS server on the intranet is authoritative for the zone so that .