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forwarders.help
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1996-05-12
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2KB
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47 lines
Forwarders
Introduction
Your DNS may have difficulties to do name resolution outside of the
domain it manages. It may defer this work to another DNS which will do
the work and return the result to it.
11.. WWhhyy ddooiinngg tthhiiss
If your DNS is behind a firewall, it can't reach the _I_n_t_e_r_n_e_t. It
can't fulfill one of its main task, which is to provide name
resolution (its a DNS where S stand for server :-) ). By pointing to a
forwarder (often a caching only DNS running on the firewall itself),
the problem is solved.
Another reason appear when a DNS is located at the end of a slow link.
Instead of trying to solve itself all the query it will send the
request to a forwarder at the other end of the link. Often the second
DNS has a higher usage than the first, thus already has a greater
knowledge. It is in position to answer the query right away using its
large cache.
22.. TTaasskk
Just enter the IP address of the DNS you want to use. The order is
important. Put the best first. Put more than one as backup.
33.. WWhhaatt hhaass ttoo bbee ddoonnee ttoo aa DDNNSS ssoo iitt aacccceepptt ttoo pprroocceessss ffoorrwwaarrddeedd
rreeqquueessttss
NNootthhiinngg..
44.. //vvaarr//nnaammeedd//rroooott..ccaacchhee
If your DNS is deferring request to another DNS, the file
//vvaarr//nnaammeedd//rroooott..ccaacchhee is not needed!
WWrroonngg!!
This file provide the bootstrap knowledge required to resolve name in
other domain. Without this file, your DNS will simply think that
nothing else exist except the domains it serves. It won't look
further.
This is why _L_i_n_u_x_c_o_n_f always try to add it to your DNS configuration!