153 lines
2.8 KiB
HTML
153 lines
2.8 KiB
HTML
<HTML
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>Handling Name Server Lookups</TITLE
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HREF="index.html"><LINK
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TITLE="IP Masquerade and Network Address Translation"
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HREF="x-087-2-ipmasq.html"><LINK
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TITLE="Configuring IP Masquerade"
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>Chapter 11. IP Masquerade and Network Address Translation</TD
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NAME="X-087-2-MASQ.NAMELOOKUPS"
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>11.4. Handling Name Server Lookups</A
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></H1
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><P
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>
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Handling domain name server lookups from the hosts on the LAN with IP
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masquerading has always presented a problem. There are two ways of
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accomodating DNS in a masquerade environment. You can tell each of the
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hosts that they use the same DNS that the Linux router machine does,
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and let IP masquerade do its magic on their DNS
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requests. Alternatively, you can run a caching name server on the
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Linux machine and have each of the hosts on the LAN use the Linux
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machine as their DNS. Although a more aggressive action, this is
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probably the better option because it reduces the volume of DNS
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traffic travelling on the Internet link and will be marginally faster
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for most requests, since they'll be served from the cache. The downside
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to this configuration is that it is more complex. <A
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HREF="x-087-2-resolv.named.html#X-087-2-RESOLV.NAMED-CACHINGONLY"
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>Section 6.3.4</A
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>,” in Chapter 6, describes how to configure
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a caching name server.</P
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>Configuring IP Masquerade</TD
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