̾??

resolver — ?꥾?????????ե?????

????

resolv.conf

????

resolver(3) ?ϥ??󥿡??ͥåȥɥᥤ???͡??ॷ???ƥ??ؤΥ??????????󶡤??? C ?饤?֥????Υ롼???󷲤Ǥ??? ?꥾?????????ե??????ϡ??Ϥ????ƥ꥾???Х롼???󤬥ץ??????ˤ??äƸƤӽ? ???줿?Ȥ????ɤ߹??ޤ??????????ޤ??Ǥ??ޤ??? ?ե??????Ͽʹ֤??ɤ????褦???߷פ????Ƥ??ꡢ?͡??ʼ????Υ꥾???о????? ?󶡤??롢?ͤĤ??Υ?????ɤΥꥹ?Ȥ??ޤ??Ǥ??ޤ???

???̤˹??????줿?????ƥ??Ǥϡ????Υե???????ɬ?פǤϤ????ޤ????? ?䤤???碌??????ͣ???Υ͡??ॵ???Фϥ????????ޥ??????ˤ??ꡢ?ۥ???̾ ?????ɥᥤ??̾?????ꤵ?졢?ɥᥤ???θ????ѥ??????Υɥᥤ??̾???????? ?????ޤ???

?͡??????ꥪ?ץ??????ϰʲ????̤??Ǥ???

nameserver

?꥾???Ф??䤤???碌?򤹤??͡??ॵ???ФΥ??󥿡??ͥåȥ??ɥ쥹 (?ɥå?ɽ??)?Ǥ??? ??????????? 1 ?ĤŤġ??? MAXNS (?????Ǥ? 3)???ޤǤΥ͡??ॵ???Ф????ҤǤ??ޤ??? ʣ???Υ????Ф????Ҥ????Ƥ??????硢?꥾???Х饤?֥????ϵ??Ҥ??줿???? ?䤤???碌???Ф??ޤ??? nameserver ?????ȥ꤬???Ҥ????Ƥ??ʤ????硢?ǥե????ȤǤϥ????????ޥ??????Υ͡??? ?????Ф????Ѥ??ޤ? (?????ǻȤ????륢?르?ꥺ???ϰʲ??Τ褦?ˤʤ??ޤ??? ?ޤ????????͡??ॵ???Ф??䤤???碌?????ߤޤ??? ?????䤤???碌???????ॢ???Ȥˤʤ??С? ???Υ͡??ॵ???Ф??䤤???碌?????ߡ????????͡??ॵ???Ф??ʤ??ʤ??ޤ?³???ޤ??? ???????ʤ????硢???ΰ?Ϣ???䤤???碌?λ??ߤ????ȥ饤?????? ????ã?????ޤǷ????֤??ޤ?)??

domain

?????????ɥᥤ??̾?? ???Υɥᥤ?????Ǥ?̾?????䤤???碌?ΤۤȤ??ɤ????????????ɥᥤ???ˤ????? û??̾???????Ѥ??뤳?Ȥ??Ǥ??ޤ??? domain ?????ȥ꤬???Ҥ????Ƥ??ʤ????硢 gethostname(3) ???????????????ۥ???̾?????ɥᥤ???????ꤷ?ޤ??? ?ɥᥤ?????Ϻǽ??? ‘.’ ?ʹߤ????ƤȤʤ??ޤ??? ?ۥ???̾???ɥᥤ???????ޤ??Ǥ??ʤ????硢?ǽ?Ū?ˤ? ?롼?ȥɥᥤ?󤬻??Ѥ????ޤ???

search

?ۥ???̾Ĵ???Τ????θ????ꥹ?ȡ? ?̾?????ꥹ?Ȥϥ????????ɥᥤ??̾???????ꤵ???ޤ??? ?ǥե????ȤǤϡ??????????ɥᥤ??̾?Τߤ??ޤߤޤ??? ?????ꥹ?Ȥϡ? search ??????ɤθ??˥??ڡ????ޤ??ϥ??֤Ƕ??ڤ??줿 ?ɥᥤ?󸡺??ѥ?̾?????󤹤뤳?Ȥ? ?ѹ??Ǥ??ޤ??? ?ۤȤ??ɤΥ꥾???Ф??䤤???碌?ϡ??????ѥ??γƹ??????Ǥ????פ??륨???ȥ꤬ ???Ĥ????ޤǽ??˻?ޤ??? ???Ҥ??줿?ɥᥤ???Υ????Ф??????????ǤϤʤ????硢???ν???????®??¿???? ?ͥåȥ???ȥ??ե??å???ȯ??????????ǽ???????뤳?Ȥȡ????????Τ????줫?? ?ɥᥤ???˴ؤ??ơ????Ѳ?ǽ?ʥ????Ф? 1 ?Ĥ?¸?ߤ??ʤ??????ˤ??䤤???碌?? ?????ॢ???Ȥ??뤳?Ȥ????դ???ɬ?פ??????ޤ???

???ߤΤȤ??????????ꥹ?Ȥ? 6 ?ɥᥤ?󡢷? 256 ʸ???????¤????ޤ???

sortlist

sortlist ???Ѥ??? gethostbyname ?ˤ????֤????륢?ɥ쥹?򥽡??ȤǤ??ޤ??? sortlist ?? IP ???ɥ쥹?ȥͥåȥޥ??????Ȥǻ??ꤵ???ޤ??? ?ͥåȥޥ????ϥ??ץ??????Ǥ??ꡢ ?ǥե????ȤΥͥåȥޥ????ϥͥåȤ??Ф??뼫???ʥͥåȥޥ??? (natural netmask) ?Ǥ??? IP ???ɥ쥹?ȥ??ץ??????Υͥåȥޥ??????Ȥϥ????å????Ƕ??ڤ??ޤ??? 10 ?Ȥޤǻ?????ǽ?Ǥ??? ???Ȥ??ơ?

sortlist 130.155.160.0/255.255.240.0 130.155.0.0

options

options ?ˤ????꥾???Ф??????ѿ????????Ǥ??ޤ??? ʸˡ??

options option ...

?Ǥ??ꡢ option ?ϰʲ??Τ????줫?Ǥ?:

debug

_res.options ?? RES_DEBUG ?????ꤷ?ޤ???

ndots:n

?ǽ????????䤤???碌 ???Ԥ????????ˡ? res_query() (resolver(3) ????) ??Ϳ????????̾???˴ޤޤ????٤??ɥåȿ??????ͤ????ꤷ?ޤ??? n ?Υǥե????Ȥ? “1” ?Ǥ??? ?????ϡ?̾?????˥ɥåȤ??????С? search list ???Ǥ??ɲä????????ˡ? ????̾?????ޤ?????̾?Ȥ??ƻ???뤳?Ȥ???̣???ޤ???

timeout:n

?꥾???Ф??㤦?͡??ॵ???Ф??䤤???碌?ˤ????ޤǤˡ? ???⡼?ȤΥ͡??ॵ???Ф????α??????ԤĽ??????֤????ꤷ?ޤ??? ?꥾???Фϡ????ߤ??䤤???碌???Υ??ȥ饤???ˤϤ??ν??????֤????? Ĺ?????ֱ??????ԤäƤ??褤?Ǥ??? ?ʤ??ʤ顢?ؿ??ؿ?Ū?ʥХå????դ? ?????ॢ?????ͤ?Ŭ?Ѥ????뤫???Ǥ??? ?ÿ??ǿ??????졢?ǥե????Ȥ? RES_TIMEOUT ?Ǥ??ꡢ???Ĥ??????????ͤ? RES_MAXRETRANS (<resolv.h> ????) ?Ǥ???

attempts:n

?꥾???Ф??????????ƸƤӽФ????Υ??ץꥱ?????????˥??顼???֤????ˡ? ?ƥ͡??ॵ???Ф˲????䤤???碌?????????뤫???ꤷ?ޤ??? ?ǥե????Ȥ? RES_DFLRETRY ?Ǥ??ꡢ???Ĥ??????????ͤ? RES_MAXRETRY (<resolv.h> ????) ?Ǥ???

no_tld_query

?꥾???Ф˥ȥåץ??٥??Υɥᥤ??̾?????ʤ????ɥåȤ??????ʤ?̾???? ???褷?ʤ??褦?ˤ????ޤ??? ???Υ??ץ??????????Ѥ??Ƥ⡢?꥾???Ф?Ϳ?????줿̾???????Ѥ???ɸ???? domain ?? search ?Υ롼???˽??????Ȥ??ɤ????ȤϤǤ??ޤ?????

options ?? RES_OPTIONS ?Ķ??ѿ??????Ѥ??ơ??????ޤ??ϥ??ֶ??ڤ??Υꥹ?ȤȤ??ƻ????Ǥ??ޤ???

domain ?? search ??????ɤ???¾Ū?Ǥ??? ???????Υ?????ɤ? 1 ?İʾ嵭?Ҥ????Ƥ??????硢 ?Ǹ??Υ?????ɤ?ͭ???ˤʤ??ޤ???

??????ɤ??ͤ?Ʊ???Ԥ?¸?ߤ???ɬ?פ????ꡢ??????? (?㤨?? nameserver) ?ϹԤ???Ƭ?ˤ???ɬ?פ??????ޤ??? ?ͤϥ?????ɤ?³???ƶ????Ƕ??ڤäƵ??Ҥ??ޤ???

??Ϣ?ե?????

/etc/resolv.conf

resolv.conf ?? /etc ??¸?ߤ??ޤ???

??Ϣ????

gethostbyname(3), resolver(3), hostname(7), named(8) Name Server Operations Guide for BIND.

????

resolv.conf ?ե??????ե????ޥåȤ? 4.3BSD ???о줷?ޤ?????