Setevaya fajlovaya sistema NFS
- Network File System.
Standartnoj setevoj fajlovoj sistemoj dlya UNIX'a yavlyaetsya NFS.
Lyubaya Unix-mashina umeet montirovat' po protokolu NFS udalennye
fajlovye sistemy i ispol'zovat' ih kak svoi sobstvennye, a tak
zhe mozhet vydelyat' svoi katalogi dlya drugih mashin. Vyglyadit eto
primerno tak:
mount -F nfs udalennaq.mashina:/katalog_tam /katalog
ili, esli u vas BSD ili Linux
mount -o rsize=8192,wsize=8192 mashina:/katalog_tam /katalog
ls -al /katalog
Hotya NFS byl kogda-to razrabotan dlya Unix'a, imeetsya realizaciya
NFS dlya MSDOS-ovskih PC. |ti pakety prinyato nazyvat' svodnym
imenem PC/NFS (Ne putat' s nazvaniem "PC-NFS" - eto realizaciya
PC/NFS ot firmy "Sun Select"). T.e. PC'yuk, na kotorom zapushchen
NFS dlya PC, mozhet montirovat' v kachestve setevyh diskov
katalogi Unix'ovskoj mashiny, kotorye ona vydelyaet v NFS. -
Fakticheski, PC/NFS daet dlya PC te zhe samye vozmozhnosti, chto i
Netware - udalennyj setevoj disk i udalennyj setevoj printer.
Raznica lish' v tom, chto Unix-host, pomimo pozvoleniya NFS-eniya
sebya, v sostoyanii zanimat'sya i svoimi sobstvennymi zadachami, a
server Netware nichem krome obsluzhivaniya svoih klientov,
izobrazhaya dlya nih disk s ethernet'om, zanimat'sya ne
prisposoblen, no rabotaet bystree raza v 1.5-2. Nu i zanimayut
NFS-nye rezidenty poryadka 100 Kb operativnoj pamyati, v to vremya
kak Netwar'nye - poryadka 50.
2. Ocenochnye skorosti paketov PC/NFS razlichnyh proizvo-
ditelej: 486dx2/66, adapter wd8013 16 bit:
Paket: chtenie Kb/sek zapis'
NFS for PC
PC-NFS 4.0 220 120
PC-NFS 5.0(**) 220 120
Pathway 350 170
PCTCP 3.0 350 200
TSOFT (*) 200 100
XFS (*) 500 50
Chameleon NFS(**) 2-e mesto po rezul'tatam testov
Unix for PC
Linux/NFS(*) 400 350
FreeBSD/NFS(*) 900 300
Unixware/NFS 400 300
Prochie
Netware 3.11 500 600
NW Lite 400 500
WFW (Samba) 150 150
Lantastic ? ?
(*) - uslovno-besplatnye ili besplatnye pakety
(**) - zashchishchen ot nelicenzirovannogo kopirovaniya
Dlya sravneniya: skorost' chteniya/zapisi NFS mezhdu dvumya
SUN SPARCstation i/ili IBM/RS6000 900/400 Kb/sek
3. Dlya togo, chtoby Unix-mashina sluzhila NFS serverom
Na nej dolzhny byt' zapushcheny sleduyushchie demony:
rpc.portmap - demon portov RPC (Remote Procedure Call)
(poskol'ku NFS ispol'zuet RPC)
(Na Motorole ne trebuetsya.)
mountd - obsluzhivanie komand montirovaniya (on reshaet -
razreshit'/ ne razreshit')
nfsd - neposredstvennoe obsluzhivanie protokola NFS
biod - keshirovanie NFS-chtenij na kliente
(tol'ko v SunOS)
pcnfsd - provodit dopolnitel'nuyu "avtorizaciyu" pol'zo-
vatelej na PC/NFS klientah. Poskol'ku MSDOS
ne zanimaetsya uchetom i registraciej pol'zova-
telya, pcnfsd sam sprashivaet u PC-ishnogo
user'a ego imya i parol'.
(ne obyazatelen, no zhelatelen)
Obychno vse eti demony zapuskayutsya na urovne vypolneniya 3. Pos-
motrite, s bol'shoj veroyatnost'yu vy obnaruzhite na svoej mashine
fajl s nazvaniem napodobie:
/etc/rc3.d/S22nfs - prednaznachen dlya zapuska NFS-servera
Dolzhno byt' ukazano, kakie imenno katalogi, razreshaetsya "vi-
det'" po NFS, i kakim imenno mashinam eto razreshaetsya.
|ti katalogi ukazyvayutsya v fajle
/etc/dfs/dfstab i eksportiruyutsya yavnoj komandoj
shareall ili share (esli u vas SVR4)
ili v fajle
/etc/exports i eksportiruyutsya yavno komandoj
exportfs -a (esli u vas kakoj libo drugoj UNIX)
Obychno, na mashine so svezheustanovlennym Unix'om NFS server ne
aktivizirovan. CHtoby on zapustilsya, sistemnyj administrator
dolzhen obespechit' vypolnenie uslovij perechislennyh v predydushchem
punkte. Dlya etogo dostatochno:
Posle zagruzki perehodit' na uroven' vypolneniya 3.
V fajle /etc/inittab ispravit' stroku
is:2:initdefault:
na stroku
is:3:initdefault:
Zapuskat' pcnfsd - demona "avtorizacii" PCNFS'nyh pol'zovatelej
V fajl /etc/rc3.d/S22nfs vstavit' komandu zapuska demona:
/usr/lib/nfs/pcnfsd
Iz menyu sysadm v network_services / remote_files /
local_recources / share / nfs zadat' katalogi, kotorye vy raz-
reshaete "razdavat'" po NFS. Naprimer, proeksportirujte katalog
/home
CHtoby ispravleniya v /etc/inittab podejstvovali, perezagruzite
unix komandoj
shutdown -y -g0 -i6
V fajle /etc/rc.d/rc.inet2 raskommentirujte stroki, zapuskayushchie
demonov
rpc.portmap
rpc.nfsd
rpc.mountd
rpc.ugidd
V fajl /etc/exports vstav'te stroku
/ (rw)
Perezagruzites'
V fajl /etc/exports vstav'te stroki...
/home
/usr
Perezagruzites'
V fajle /etc/dfs/dfstab vstav'te stroki dlya eksportiruemyh faj-
lovyh sistem. (Format ukazan v kommentariyah v etom fajle)
Perezagruzites'
5. ESHCHE ODNA SETEVAYA FAJLOVAYA SISTEMA. RFS. DFS.
RFS - Remote File Sharing. Tozhe setevaya fajlovaya sistema. NFS -
porozhdenie BSD Unix'a, RFS - System V Unix'a. Naznachenie takoe
zhe, kak i u NFS. Kakih libo preimushchestv po sravneniyu s NFS ne
imeet. YArko vyrazhennyh nedostatkov, pozhaluj, tozhe. Znachitel'no
menee rasprostranena, chem NFS. Ne imeet automounter'a. Klientov
RFS for MSDOS PC net. Zato RFS podderzhivaet zahvat i blokirovku
fajlov, i special'nye fajly. Aktivizirovat' RFS vryad li imeet
smysl. Dejstvitel'no, zachem nam vtoroj General'nyj sekretar'?
DFS - Distributed File System. Tozhe setevaya fajlovaya sistema.
Vot i vse, chto ya mogu pro nee skazat'.
Last-modified: Thu, 06 Aug 1998 14:04:49 GMT