̾??

nsswitch.conf — ?͡??ॵ???ӥ??????å????????ե?????

????

nsswitch.conf ?ե??????? C ?饤?֥????Ǥ? nsdispatch(3) (?͡??ॵ???ӥ? ?????å??ǥ????ѥå???) ?롼???????ɤΤ褦?˺?ư?????뤫?? ???ꤷ?ޤ???

?????????ե??????ϡ?host, user (password), group ?ʤɤ˴ؤ??? ???????????͡??ʥǡ????١?????Ĵ?٤뤿???? ?ץ??????򥳥??ȥ????뤷?ޤ??? ?ƥǡ????١????? (?????????ե????롢DNS?? NIS ?Τ褦??) ?????????????????졢 ???Υ??????????ꤹ?????? nsswitch.conf ?????ꤷ?ޤ???

nsswitch.conf ?γƥ????ȥ??ϥǡ????١???̾?ȡ????ڡ????Ƕ??ڤ??줿 ???????Υꥹ?Ȥǹ????????Ƥ??ޤ??? ?ƥ??????ˤϡ??ꥹ?Ȥμ??Υ????????Ȥ????????ߤΥ??????ǽ??????ˤ??뤫 ?????????????????˽񤱤ޤ??? ?ƴ????ϡ?1 ?Ĥ⤷???ϡ??????ʾ??Υ??ơ??????????ɤȡ? ???Υ??ơ??????????ɤ?ȯ???????ݤ˹Ԥ?ư???????Ω?äƤޤ???

??????

?ʲ??Υ????????????????Ƥ??ޤ?:

??????: ????
files: /etc/hosts ?? /etc/passwd ?ʤɤΥ????????ե????롣
dns: ???󥿡??ͥåȥɥᥤ???͡??ॷ???ƥࡣ “hosts” ?? ‘networks’ ?ϡ? IN ???饹?????Ѥ???????¾???Ƥ? HS ???饹 (Hesiod) ?????Ѥ??ޤ???
nis: NIS (?????? YP)
compat: “passwd” ?? “group” ?Υǡ????١????? ‘+/-’ ?򥵥ݡ??Ȥ??ޤ??? ???줬???????硢?????ȥ??Υ??????ϡ??????ΤߤǤ???

?ǡ????١???

?ʲ??Υǡ????١????ϡ??ʲ??? C ?饤?֥????ؿ??ˤ??äƻ??Ѥ????ޤ?:

?ǡ????١???: ??????
group: getgrent(3)
hosts: gethostbyname(3)
networks: getnetbyname(3)
passwd: getpwent(3)
shells: getusershell(3)

???ơ???????????

?ʲ??Υ??ơ??????????ɤ????Ѳ?ǽ?Ǥ?:

???ơ???????????: ????
success: ?׵ᤷ???????ȥ꤬???Ĥ????ޤ?????
notfound: ???Υ??????ˤϡ??????ȥ꤬?????ޤ????Ǥ?????
tryagain: ?????????ӥ??????֤Ǥ????ƻ??Բ?ǽ?Ǥ???
unavail: ???????α??????ʤ??????????ȥ꤬?????Ƥ??ޤ???

??????????

???줾???Υ??ơ??????????ɤˤ????ơ??ʲ??Υ????????󤬲?ǽ?Ǥ?:

??????????: ????
continue: ???Υ??????????ԡ?
return: ???ߤη??̤????롣

?ե??????ե????ޥå?

nsswitch.conf ?? BNF ??ʸ?ϰʲ????̤??Ǥ?:

<entry>: ::= <database> ":" [<source> [<criteria>]]*
<criteria>: ::= "[" <criterion>+ "]"
<criterion>: ::= <status> "=" <action>
<status>: ::= "success" | "notfound" | "unavail" | "tryagain"
<action>: ::= "return" | "continue"

?ƥ????ȥ??ϥե????????ο??????Ԥ??饹?????Ȥ??ޤ??? ?????? ‘#’ ?ϡ??????ޤǥ??????ȤȤ????ޤ??? ???Ԥ?̵?뤵???ޤ??? ?????? ‘\’ ???????????ϲ??Ԥ?̵?뤷?? ???ιԤ򸽺ߤιԤ?³???Ȥ??ޤ??? ???ƤΥ????ȥ??ϡ???ʸ???Ⱦ?ʸ???????̤??ޤ?????

?ǥե????ȴ????? “success” ?ξ????? return ?ˤʤꡢ?????ʳ??ξ????? continue ?ˤʤ??ޤ??? (?Ĥޤꡢ [success=return notfound=continue unavail=continue tryagain=continue])

compat ?⡼??: +/- ???󥿥å???

????Ū?ʥޥ??????????????ˤ????ơ? ‘+’ ?? ‘-’ ʸ???ϡ??桼???ѥ???ɤ? ???롼?׾????? NIS ?????????????褦?????ꤹ?뤿???˻Ȥ????ޤ??? NIS ?ʤɤ????ۤ????Ƥ??륽?????˥????????????̤???ˡ?? nsswitch.conf ???󶡤??ޤ?????????????ñ???? “compat” ?????ꤹ????????Ū??ư????ˡ???󶡤??ޤ???

“passwd_compat: source” ?????ꤹ???? ‘+/-’ ??ͳ?ǥ??????????줿?????????ؤ? ???????˻??Ѥ??뤳?Ȥ??Ǥ??ޤ??? ???ξ????? “source” ?ˤϡ? ‘dns’, ‘nis’ ?? ‘files’, ‘compat’ ?ʳ??Τ???¾?Υ??????????ƤϤޤ??ޤ???

????

????Ū?ʡ?¿???Υǡ????١????ˤϡ? getXXXent() ???????????ؿ????????ޤ??? (?ƥ?????????????) ?ǡ????١??????????????ե??????ΤȤ??ϡ????ˤ??ʤäƤ??ޤ????? ¿???Υ??????ξ????ϡ? ?ۤȤ??ɰ?̣???ʤ??????????ǤϤ????ޤ????? ???Υ??󥿥ե??????Ϥޤ??ߴ????Τ??????Ѱդ????Ƥ??ޤ????? ?????????????ʥ????ȥ????󶡤Ǥ??ʤ????⤷???ޤ????? ?ޤ??ϡ????̤ä????????ݻ????Ƥ???ʣ???Υ??????????ꤷ?????硢 ??ʣ?????????ȥ꤬?֤????뤫?⤷???ޤ?????

?????μ????ȡ????ߤμ????Ȥθߴ??????μ¤ˤ??뤿???? “compat” ???????ϻ??ꤹ???ǡ????١????ˡ?ñ?Ȥ?¸?ߤ??ʤ????Фʤ??ޤ?????

?ǥե????ȥ??????Υꥹ??

???????????????ˤ????? ???餫????ͳ?? nsswitch.conf ??¸?ߤ??Ƥ??ʤ??????ޤ??? ?礱?Ƥ????????줿?????ȥ꤬???ä????? nsdispatch(3) ???׵ᤵ?줿?ǡ????١????ˤ? “files” ?Υ????ȥ????ǥե????ȤȤ??ޤ??? ?㳰?ϰʲ????̤??Ǥ?:

?ǡ????١???: ?ǥե????ȥ??????Υꥹ??
group: compat
group_compat: nis
hosts: files dns
passwd: compat
passwd_compat: nis

??Ϣ?ե?????

/etc/nsswitch.conf: nsswitch.conf ?ե??????? /etc ?ˤ????ޤ???

??

?ۥ??Ⱦ????? /etc/hosts ???θ? DNS ?Ǹ????????桼???????? NIS ???θ? files ?Ǹ????????ˤϰʲ??????Ѥ??Ƥ???????:

hosts:: files dns
passwd:: nis [notfound=return] files
group:: nis [notfound=return] files

“[notfound=return]” ?δ????ϡ?"NIS ?? notfound ???֤??????硢files ?ϸ??????ʤ?" ?Ȥ????????ˤʤ??ޤ??? NIS ?????Ф??????󤷤Ƥ????????????ơ?NIS ?Τߤ? ?????ʾ????Ȥ??Ƽ??갷???ޤ???

??

?????ƥब NO_NIS ?ǥ????ѥ??뤵???Ƥ??????? ‘nis’ ?Υ????ȥ??ϳ????Ƥ?????????

??Ϣ????

nsdispatch(3), resolv.conf(5), named(8), ypbind(8)

????

nsswitch.conf ?ե??????ե????ޥåȤ? FreeBSD 5.0 ?ǤϤ??????о줷?ޤ????? ?????? NetBSD 1.4 ?ǤϤ??????о줷?? NetBSD ?ץ????????Ȥ??饤???ݡ??Ȥ????ޤ?????

????

Luke Mewburn ⟨lukem@netbsd.org⟩ ?? ULTRIX svc.conf(5) ?? Solaris nsswitch.conf(4) ?ޥ˥奢???ڡ????????Υ????ǥ????򸵤ˡ? ???μ?ͳ?˺????۲?ǽ?ʥ͡??ॵ???ӥ? ?????å??μ????򵭽Ҥ??ޤ?????