Cu 1 : a/ c trng v nhc im ca Linux u im : Linh hot, uyn chuyn, an ton cao, Thch hp cho qun tr mng Chy thng nht trn cc h thng phn cng Free Nhc im : * i hi ngi dng phi thnh tho: Trc kia vic s dng v cu hnh Linux c xem l mt cng vic ch dnh cho nhng chuyn gia.Hu nh mi cng vic u thc hin trn cc dng lnh v phi cu hnh nh sa trc tip cc file. Mc d trong nhng phin bn gn y, cc HH Linux c nhng ci tin ng k, nhng so vi Windows tnh thn thin ca Linux vn cn l mt vn ln. y l mt trong nhng nguyn nhn ch yu khin Linux mc d c rt nhiu c tnh k thut tt nhng vn cha n c vi ngi dng cui. * Tnh tiu chun ha: Linux c pht hnh min ph nn bt c ai cng c th t mnh ng gi, phn phi theo nhng cch ring. Hin ti c kh nhiu bn Linux pht trin t mt nhn ban u cng tn ti nh: RedHat, SuSE, Knoppix.. Ngi dng phi t so snh xem bn no l ph hp vi mnh. iu ny c th gy kh khn cho ngi dng, nht l nhng ngi cn c kin thc v tin hc hn ch * S lng cc ng dng cht lng cao trn Linux cn hn ch:Mc d Windows c sn phm no th Linux cng gn nh c phn mm tng t.(VD: OpenOffice trn Linux tng t nh MSOffice, hay GIMP tng t nh Photoshopv..v..) Tuy nhin cht lng nhng sn phm ny l cha th so snh c vi cc sn phm vit cho Windows. * Mt s nh sn xut phn cng khng c driver h tr Linux: Do hin nay Linux cha ph bin bng Windows nn nhiu nh sn xut khng h tr cc driver chy trn Linux. Tuy nhin bn vn c th tm thy cc driver ny do ai trong cng ng m ngun m vit. b/ So snh Linux v window : 1. u im: - Linux: Tc nhanh, khng i hi cu hnh my cao - Windows: Giao din 3D p mt, chuyn i nhanh gia cc ca s, tnh nng search mnh 2. Nhc im: - Linux: Giao din n gin do lc bt ti u ha, khng c chc nng plug and play - Windows: Vic nhiu chng trnh hin vn cha tng thch vi Vista l mt nguyn nhn khin nhiu ngi dng khng mun s dng 3. Gi c: - Linux: Min ph (nu bn cn h tr k thut th c th mt ph) - Windows: 365 $ cho bn Premium Edition.gi ca bn Ultimate Edition l 648 $ 4. Audio: - Linux: C y cc tnh nng: chi nhc , rip nhc bng Sound Juicer, Rhythmbox thc hin chc nng t chc v nghe Internet radio, Serpentine burn CD v Sound Recorder ghi m) - Windows: Tt hn Linux. Phin bn Windows Media Player mi cho php bn ripCD, mua cc bn nhc mi v lin kt ti 1 Mp3 player 5. Video & image: - Linux: F-spot phc v vic sao nh t my nh v t chc thnh album. Tnh nng xem video ca Totem Movie Video c nh gi cao - Windows: Windows Media Center cho php bn duyt nh, xem slideshow, chi DVD,1

xem v ghi TV t web, download phim v xem video gia nh. 6. Lm vic: - Linux: Open Office hin c nh gi rt tt v hon ton min ph - Windows: Bn s mt 588 $ mua Windows Vista Business c phn mm fax. Microsoft Office c gi 608 $ 7. Li h iu hnh: - Linux: Khng c - Windows: Microsoft thng bo l Vista l bn Win hon chnh nht nhng ngi s dng vn phn nn rt nhiu 8. Kh nng chng virus: - Linux: t b nh hng ca Virus. Phn mm Aegis Virus Scanner tch hp sn c th chy ch nn - Windows: Bn cn phi mua mt vi phn mm chng virus, kiu nh Norton Internet Security 2007 vi gi khong 81,1 $

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2. Cu 2 : Kin trc linux H iu hnh Linux gm c: ht nhn (kernel), shell, cc tin ch v cc ng dng. u tin chng ta s tm hiu xem ht nhn (kernel) l g ? Kernel l trung tm iu khin ca h iu hnh Linux, cha cc m iu khin hot ng ton b h thng. Kernel c pht trin khng ngng, thng c hai phin bn, mt phin bn dng pht trin mi nht v mt bn n nh nht. Kernel c thit k theo dng modul, do vy kch thc tht ca Kernel rt nh. Chng ch ti nhng b phn cn thit ln b nh. Nh vy so vi h iu hnh khc Linux khng s dng lng ph b nh nh khng ti mi th ln trong khi cc h iu hnh khc ti tt c ln m khng quan tm xem n c c s dng hay khng. Kernel c v nh l tri tim ca h iu hnh Linux, ban u pht trin cho dng CPU Intel 386, im mnh ca b CPU ny l kh nng qun l b nh. Kernel ca Linux c th truy xut ti ton b tnh nng phn cng ca my. Yu cu ca cc chng trnh cn rt nhiu b nh, trong khi b nh h thng rt nh, h iu hnh s dng khng gian hon i (Swap space) lu tr cc d liu x l ca chng trnh. Swap space cho php ghi cc trang b nh xut cc v tr dnh sn trong a coi n nh l phn m rng ca vng nh chnh. Bn cnh s dng Swap Space, Linux cn h tr nhng c tnh sau: * Bo v vng nh gia cc tin trnh, iu ny khng cho php mt tin trnh lm tt ton b h thng. * Ch ti cc chng trnh khi cn thit. Shell cung cp tp lnh cho ngi dng thao tc vi Kernel thc hin cng vic. Shell c cc lnh t ngi dng v x l. Ngoi ra Shell cung cp mt s c tnh khc nh chuyn hng xut nhp ngn ng nhp to cc tp tin tng t nh tp tin BAT trong DOS C nhiu loi Shell c s dng trong Linux. im quan trng phn bit cc Shell vi nhau l b lnh Shell. V d : C Shell th s dng cc lnh tng t ngn ng C, Bourne Shell th s dng cc ngn ng lnh khc Shell s dng chnh trong Linux l GNU Bourne Again Shell. Shell ny l Shell pht trin t Bourne Shell, l Shell dng chnh trong UNIX vi nhiu tnh nng mi nh: iu khin cc tin trnh, cc lnh history, tn tp tin di Cc tin ch khc trong Linux c ngi dng thng xuyn tng tc. N c dng cho nhiu th nh thao tc tp tin, a nn, sao lu tp tin Tin ch trong Linux c th l cc lnh thao tc hay cc chng trnh giao din ha. Hu ht cc tin ch trong Linux l sn phm ca chng trnh GNU. Linux c sn rt nhiu tin ch nh chng trnh bin dch, trnh g li, son vn bn Tin ch c th c s dng bi ngi dng hoc h thng, mt s tin ch c xem l chun trong h thng Linux nh Passwd, ls, ps, vi Cc chng trnh ng dng khc vi cc tin ch, cc ng dng nh trong chng trnh Word, h thng qun tr c s d liu l cc chng trnh c phc tp ln v c cc nh sn xut vit ra

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Cu 3 : Thit b a/ Quy tc qun l thit b trong Linux : Linux xy dng c ch truy xut n tt c cc loi a v thit b u dng tp tin (tp tin thit b) v lu trong th mc /dev. Linux quy c t tn nh sau: - a mm: fd - a cng vt l th nht: hda - a cng vt l t hai: hdb - Nu a cng theo tiu chun SCSI th gi l: sda, sdb, Cc thit b USB, Linux xem nh l thit b SCSI (v d nu my c mt a cng SCSI th USB s l sdb1). Cc phn vng (partitions) c nh s sau tn a. V d: hda1, hda2, sda1, sdb1 ( A), fd1 ( B) Cc phn vng chnh (primary) hoc phn vng m rng (extended) c nh t 1 -> 4. Cc phn vng logic (nm trong phn vng m rng) nh s t 5 tr i. b/ Cc truy xut a : Cng tng t nh Window, trong Linux cng c khi nim ng dn (path). Tuy nhin, c 2 im cn lu : - Th nht, s dng k t s tri (/) lm k t phn cch th mc v tp tin. - Th hai, khng s dng k t a, m dng k t / u ng dn (th mc gc). V d: - /usr/local/dev - /dev/hda Khi khi ng h iu hnh, Linux ch kt gn cho phn vng chnh (ni cha nhn Linux) bng k t / (th mc gc). Cc thng tin ca phn vng khc c Linux t trong th mc /dev ca phn vng chnh. Nh vy mc d tt c cc file trong Linux u c t trong cng mt cy th mc, song chng c th c lu tr trn cc b nh ngoi khc nhau nh a cng hay CD-ROM. Mi thit b nh cng c th c h thng file (file system) khc nhau nh FAT, NTFS, ext2, gn mt h thng file trn thit b lu tr vo cy th mc chnh ta dng lnh mount.

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Cu 4 : a/ file /etc/passwd : Tp tin /etc/passwd ng mt vai tr quan trng vi h thng Unix/Linux. Mi ngi u c th c c tp tin ny nhng ch c root mi c quyn thay i n. Tp tin /etc/passwd c lu di dng text nh i a s cc tp tin cu hnh khc ca Linux. Mi dng trong file ny tng ng vi mt user. Dng u tin ca tp tin /etc/passwd m t thng tin cho user root (ch l tt c nhng ti khon c user_ID = 0 u l root), tip theo l cc ti khon khc ca h thng y l cc ti khon khng c tht v khng th login vo h thng), cui cng l cc ti khon ngi dng thng.

Name : password : UID : GID : comment : home directory : shell Mi dng trong file tng ng vi by trng thng tin ca mt ngi dng, v cc trng ny c ngn cch nhau bi du :. ngha ca cc trng thng tin ln lt nh sau: Ct 1: tn ngi s dng dng ng nhp (thng trn 8 k t). Ct 2: m lin quan n passwd. Linux lu m ny trong tp tin /etc/shadow ch c root mi c quyn c. Ct 3:4: user ID:group ID Ct 5: tn y ca ngi s dng. Ct 6: th mc c nhn, thng l /home/username (v d: /home/smith). Tt c nhng file c nhn, web pages,. s c lu tr y. Ct 7: chng trnh s chy u tin sau khi user login (thng l shell, thng c thit lp /bin/bash). b/ file etc/group : Thng tin v nhm ngi dng c lu trong file /etc/group, file ny c cch b tr tng t nh file /etc/passwd. Mi dng trong file c bn trng c phn cch bi du :. ngha ca cc trng theo th t xut hin nh sau: - Tn nhm ngi dng (groupname) - Mt khu nhm ngi dng (passwd c m ha), nu trng ny rng, tc l nhm khng yu cu mt khu. - Ch s nhm ngi dng (group id). - Danh sch cc ngi dng thuc nhm (users).

Cu 5 : Shell C ch dng lnh l cch c bn nht tng tc vi h thng my tnh. Shell cung cp mt giao din gia nhn v ngi s dng. Shell nhn lnh t ngi s dng, phn tch lnh v gi lnh ti nhn thc thi. Shell khng ch c chc nng nhn v thng dch lnh, n cn cung cp mt mi trng c th cu hnh h thng v lp trnh. Giao din ca shell thng c mt du nhc m ti bn s nhp lnh vo. Giao din ny c gi l giao din dng lnh (command line interface). C nhiu loi shell. Shell mc nh trn Linux l BASH. Shell thng kt thc bng: - $: l ngi s dng thng thng - #: ngi dng l Root (Administrator)

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Cu 6 : Tin trnh nh ngha Tin trnh Tin trnh (process) l mt chng trnh n chy trn khng gian a ch o ca n. Cn phn bit tin trnh vi lnh v mt dng lnh trn shell c th sinh ra nhiu tin trnh. u V d: dng lnh sau nnroff -man ps.1 grep kill | more us sinh ra 3 tin trnh khc nhau Cc loi tin trnh chnh trn Linux Tin trnh vi i thoi (Interactive processes) : l tin trnh khi ng v qun l bi shell, k c tin trnh foreground hoc background. Tin trnh batch (Batch processes) : Tin trnh khng gn lin n bn iu khin (terminal) v c nm trong hng i ln lt thc hin. Tin trnh n trn b nh - Daemon process Daemon processes L cc tin trnh chy di nn (background). a s cc chng trnh server cho cc dch v chy theo phng thc ny. y l cc chng trnh sau khi c gi ln b nh, i th ng cc yu cu chng trnh khch (client) tr li sau cc cng xc nh (cng l khi nim gn lin vi giao thc TCP/IP BSD socket). Hu ht cc dch v trn Internet nh mail, Web, DNS chy theo nguyn tc ny. Cc chng trnh c gi l cc chng trnh daemon v tn ca n thng kt thc bng k t d nh named, inetd K t d cui c pht m ri ra nh trong ting vit. V d named c pht m l nm . Kim tra tin trnh Cch n gin nht kim tra h thng tin trnh ang chy l s dng lnh ps (process status). Lnh ps c nhiu ty chn (option) v ph thuc mt cch mc nh vo ngi login vo h thng(xem chi tit lnh ps vo terminal g man ps). $ ps PID TTY STAT TIME COMMAND 41 v01 S 0:00 -bash 134 v01 R 0:00 ps Lnh ps hin th tt c cc process, ta c th s dng lnh ps a. Mt ngi s dng h thng bnh thng c th thy tt c cc tin trnh, nhng ch c th iu khin dc cc tin trnh ca mnh to ra. Ch c superuser mi c quyn iu khin tt c cc tin trnh ca h thng Linux v ca ngi khc. Lnh ps ax cho php hin th tt c cc tin trnh, ngay c nhng tin trnh khng gn lin n c bn iu khin (tty). Chng ta c th coi cc tin trnh ang chy cng vi dng lnh y khi ng tin trnh ny bng ps axl. Dng mt tin trnh- kill Trong nhiu trng hp, mt tin trnh c th b treo, mt chng trnh server cn nhn cu hnh mi, card mng cn thay i a ch IP , khi chng ta phi dng tin trnh ang c vn . uLinux c lnh kill thc hin cc cng tc ny. Trc tin bn cn phi bit PID ca tin trnh cn dng thng qua lnh ps. nCh c super-user mi c quyn dng tt c cc tin trnh, cn ngi s dng ch c dng cc tin trnh ca mnh. Lnh kill kill -9 PID_ca_ tin_trnh Tham s 9 l gi tn hiu dng khng iu kin chng trnh. Ch nu bn logged vo h thng nh root, nhp s PID chnh xc nu khng bn c th dng mt tin trnh khc. Khng nn dng cc tin trnh m mnh khng bit v c th lm treo my hoc dch v. Mt tin trnh c th sinh ra cc tin trnh con trong qu trnh hot ng ca mnh. Nu bn dng tin trnh cha, cc tin trnh con cng s dng theo, nhng khng tc th. V vy phi i mt khong thi gian v sau kim tra li xem tt c cc tin trnh con c dng ng hay khng.6

Trong mt s hn hu cc trng hp, tin trnh c li nng khng dng c, phng php cui cng l khi ng li my. Lnh Top Hin th s hot ng ca cc tin trnh, c bit l cc thng tin v ti nguyn h thng cng nh vic s dng ti nguyn ca tng tin trnh. Vi lnh n gin top, ta s c u11:09am up 46 days, 17:44, 2 users, load average: 0.08, 0.03, 0.01 u63 processes: 61 sleeping, 2 running, 0 zombie, 0 stopped uCPU states: 0.1% user, 0.0% system, 0.0% nice, 99.8% idle uMem: 126644K av, 121568K used, 5076K free, 0K shrd, 25404K buff uSwap: 136544K av, 9836K used, 126708K free 36040K cached u u PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME COMMAND u27568 tuanna 11 0 1052 1052 836 R 0.1 0.8 0:00 top u 1 root 0 0 124 72 68 S 0.0 0.0 0:25 init u 2 root 8 0 0 0 0 SW 0.0 0.0 0:00 kevent S % my rnh (idle) in m trn l rt quan trng. Mt my rnh di 50% l mt my qu ti v cn c xem xt. Lnh top cn cho php theo di xem c tin trnh no chim dng qu nhiu thi gian CPU cng nh truy cp a khng. uNgoi ra, mt s lnh khc nh vmstat. mpstat, sar, iostat ... cng cho php xem xt vi cc mc ch khc nhau hot ng ca my ch Cu 9 : I node

( Inide-type-Permission-Link-UID-GID-Time-Size-Data i-node khng cha tn tp tin. Tn tp tin trong cu trc th mc (directory structure). Ngi s dng khi truy xut cc tp tin trong Linux b kim sot bi quyn truy cp (trng permission trong i-node).

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Cu 10 : tn cc th mc : Th mc /home: th mc d liu ngi dng. - Trong th mc ny c cc th mc con dnh cho tng ngi dng. - Mi ngi dng c php to, cp nht, xo d liu trong th mc ca mnh. - Khi bn ng nhp vo h thng th bn s c t vo th mc ca bn, th mc ny c tn chnh l tn ngi dng m bn ng nhp. Th mc /bin: cc lnh c bn. - Cha cc lnh v cc chng trnh tin ch chun, chng hn nh ls, cat ... Th mc /usr: ng dng v th vin. Cha cc file v lnh chun s dng bi h thng. N c chia thnh nhiu th mc con: - /usr/bin: cha cc lnh v tin ch hng ngi dng. - /usr/sbin: cha cc lnh qun tr h thng. - /usr/lib: cha cc th vin dnh cho lp trnh. - /usr/doc: cha ti liu Linux. - /usr/man: cha cc file tra cu lnh. - /usr/spool: cha cc file c sinh ra bi lnh in hoc truyn tin qua mng. Th mc /sbin: cc lnh qun tr - Cha cc lnh qun tr dng khi khi ng h thng. Th mc /var: d liu bin ng - Cha nhiu file khc nhau, chng hn nh cc file th (mailbox). Th mc /dev: khai bo thit b - Cha cc giao din cho thit b nh terminal hay my in. Th mc /etc: cu hnh h thng v ng dng - Cha cc file cu hnh h thng v cc file h thng khc. Th mc /boot: kernel v cu hnh boot. Th mc /lib: th vin dng chung (shared lib). Th mc /mnt: th mc mount floppy, cdrom, ... Th mc /proc: thng tin process (pseudo-filesystem). Th mc /tmp: d liu tm.

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Cu 8 : Siu khi ( Super block ) Super Block (siu khi), trnh by trng thi ca h thng File (s lng I-node, s Disk Block, im bt u ca danh danh sch ca khi a trng (free disk blocks)). L mt dng bn ghi m t tnh trng ca h thng file. N gm cc thng tin sau: - Kch thc h thng file. - S khi cn trng trong h thng file. - Danh sch khi trng trong h thng file. - Ch s ca khi tip theo trong danh sch khi trng. - Kch thc ca danh sch inode. - S inode cn trng trong h thng file. - Danh sch inode cn trng trong h thng file. - Ch s inode tip theo trong danh sch inode trng trong h thng file. - Trng kho ca danh sch khi v inode trng. - C bo hiu super block b thay i. 1,sudo passwd root su rot useradd user1 passwd user1 useradd user2 passwd user2 2,mkdir /monhoc mkdir /monhoc/thietbi mkdir /monhoc/thietbi/hdd mkdir /monhoc/thietbi/cd mkdir /monhoc/linux/tieuluan mkdir /monhoc/linux/giaotrinh 3,touch /monhoc/thietbi/hdd/sofls link.txt ln -s /monhoc/thietbi/hdd/softlink.txt /hda0 4,touch /monhoc/thietbi/cd/hardlink.txt ln /monhoc/thietbi/cd/hardlink.txt /cda0 5,touch /monhoc/linux/giaotrinh/tieuluan.txt touch /monhoc/linux/giaotrinh/sach.txt 6,cp /monhoc/linux/giaotrinh/tieuluan.txt /monhoc/thietbi/hdd cp /monhoc/linux/giaotrinh/sach.txt /monhoc/thietbi/hdd 7, chmod 640 /home chmod 400 /monhoc/thietbi chmon 641 /monhoc/linux

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