n mn hc: Qun l h thng mng

GVHD: ThS. Nguyn V

MC LC

1MC LC

3DANH MC HNH NH

4LI NI U

5DANH MC VIT TT

6CHNG 1: TNG QUAN V QUN L H THNG MNG

61.1. Gii thiu chung v qun l h thng mng

61.2. Cc yu cu qun l h thng mng

71.3. Kin trc qun l mng

71.3.1.Kin trc qun l mng

81.3.2.C ch qun l mng

91.4. Tng quan v giao thc SNMP

91.4.1.Cc bi ton gim st cc thit b v ng dng trong h thng mng

101.4.2.Hai phng thc gim st Poll v Alert

111.4.2.1. Phng thc Poll

111.4.2.2. Phng thc Aler

121.4.2.3. So snh 2 phng thc Poll v Alert

131.4.3.Gii thiu giao thc SNMP

141.4.4.Cc thnh phn chnh ca giao thc SNMP

141.5. Khi nim giao thc SNMP

151.6. Cu trc v c im thng tin qun l SMI

161.7. Cc phng thc hot ng ca SNMP

171.8. Cc c ch bo mt ca SNMP

181.9. Cu trc bn tin SNMP

20CHNG 2: TRIN KHAI CI T V MT S TNH NNG

HYPERLINK \l "_Toc413153270" GIM ST V QUN TR MNG BNG PHN MM

HYPERLINK \l "_Toc413153271" QUEST FREE NETWORK TOOLS

202.1. Gii thiu v phn mm Quest free network tool.

202.2. Cc tnh nng chnh ca Quest Free Network Tools:

212.3. Yu cu h thng

212.4. Ci t

30KT LUN

31TI LIU THAM KHO

DANH MC HNH NH

9Hnh 1: Gim st ti nguyn my ch

10Hnh 2: Gim st lu lng thng qua cc port ca switch, router.

10Hnh 3: H thng t ng cnh bo s c tc thi

11Hnh 4: Hnh minh ha phng thc Poll

11Hnh 4: Hnh minh ha phng thc Alert

17Hnh 5 : Minh ha cc phng thc ca SNMPv1

19Hnh 6 : Cu trc bn tin SNMP

LI NI U

Th gii ngy nay c nhiu tin b mnh m v cng ngh thng tin, t mt tim nng thng tin tr thnh mt ti nguyn thc s, tr thnh sn phm hng ha trong x hi to ra mt s thay i to ln trong lc lng sn xut, c s h tng, cu trc kinh t, tnh cht lao ng v c cch thc qun l trong cc lnh vc ca x hi.

Trong nhng nm gn y, nn CNTT nc ta cng c pht trin trn mi lnh vc trong cuc sng cng nh trong lnh vc qun l x hi khc. Tuy nhin, vi s pht trin mt mng li my tnh nhanh nh vy gy ra nhng kh khn nht nh trong vic qun l cc h thng ny. Cng vic qun l h thng mng t ra l lm sao c th tn dng ti a cc ti nguyn c trong h thng v tng tin cy i vi h thng. Do , vn qun tr mng hin nay l khng th thiu c. Trong qun tr mng theo giao thc SNMP l phng php c s dng rng ri nht.

gii quyt cc vn trn, v hiu r hn s quan trng ca vic qun l h thng mng nhm em tin hnh tm hiu v giao thc SNMP v trin khai qun l th h thng mng vi phn mm Quest Free Network Tools.

Ni dung ca n bao gm 2 phn chnh :Chng 1: Tng quan v qun l h thng mng

Chng 2: Trin khai ci t v mt s tnh nng gim st v qun tr mng bng phn mm Quest Free Network Tools.DANH MC VIT TT SNMP (Simple Network Management Protocol): Giao thc qun l mng n gin MIB (Management Information Base): Thng tin qun l c bn NMS (Network Manager Stations): Trm qun l mng ACL (Access Control List) : Quyn truy cp v kim sot cc danh mc PDU (Protocol Data Unit) : n v tnh d liu giao thc SMI (Structure Management Information) : Thng tin qun l c cu t chc IOS (Internetwork Operation System) : Vn hnh h thng mng DNS (Domain Name System) : H thng tn min TFTP (Trivial File Transfer Protocol) : Giao thc truyn cc tp tin nh WMI (Windows Management Instrumentation) : Ca s qun l cc thit b.CHNG 1: TNG QUAN V QUN L H THNG MNG1.1. Gii thiu chung v qun l h thng mng

S pht trin v hi t mng trong nhng nm gn y tc ng mnh m ti tt c cc kha cnh ca mng li, thm ch c v nhng nhn thc nn tng v phng php tip cn Qun l mng cng l mt trong nhng lnh vc ang c nhng s thay i v hon thin mnh m trong c n lc tiu chun ha cc t chc tiu chun ln trn th gii v yu cu t pha ngi s dng dch v. Mt khc cc nh khai thc mng, nh cung cp thit b v ngi s dng thng p dng cc phng php chin lc khc nhau cho vic qun l mng v thit b ca mnh. Trong bi cnh hi t mng hin nay, s lng thit b v dch v rt a dng v phc tp to ra cc thch thc ln trong vn qun l mng.Nhim v ca qun l mng rt r rng v mt nguyn tc chung, nhng cc bi ton qun l c th li c phc tp rt ln. iu ny xut pht t tnh a dng ca cc h thng thit b v cc c tnh qun l cc thit b, v xa hn na l chin lc qun l phi ph hp vi kin trc mng v p ng yu cu ca ngi s dng. Mt lot cc thit b in hnh cn c qun l gm : My tnh c nhn, my trm, server, thit b u cui, thit b o kim, tng i in thoi ni ht, cc thit b truyn hnh, modem, b ghp knh, b chuyn i giao thc, thit b tng thch ISDN, cc b m ha v gii m tn hiu, thit b nn d liu, cc gateway, cc thit b chuyn mch, cc bridge, router v switch1.2. Cc yu cu qun l h thng mng

Cc c ch qun l mng c nhn nhn t hai gc , gc mng ch ra h thng mng nm cc v tr mc cao ca m hnh OSI v t pha ngi iu hnh qun l h thng mng. Mc d c rt nhiu quan im khc nhau v m hnh qun l h thng nhng u thng nht bi ba chc nng qun l c bn gm: gim st, iu khin v a ra bo co ti ngi iu hnh.

+ Chc nng gim st : c nhim v thu thp lin tc cc thng tin v trng thi ca cc ti nguyn c qun l sau chuyn cc thng tin ny di dng cc s kin v a ra cc cnh bo khi cc tham s ca ti nguyn mng c qun l vt qu ngng cho php.+ Chc nng qun l : c nhim v thc hin cc yu cu ca ngi qun l hoc cc ng dng qun l nhm thay i trng thi hay cu hnh ca mt ti nguyn c qun l no .

+ Chc nng a ra bo co : c nhim v chuyn i v hin th cc bo co di dng m ngi qun l c th c, nh gi hoc tm kim, tra cu thng tin c bo co.

Di gc ca ngi iu hnh qun l mng, mt s yu cu thng c t ra gm :

+ Kh nng gim st v iu khin mng cng nh cc thnh phn ca h thng thit b t u cui n u cui.

+ C th truy nhp v cu hnh li t xa cc ti nguyn c qun l.

+ D dng trong vic ci t, vn hnh v bo dng h thng qun l.

+ Bo mt hot ng qun l v truy nhp ca ngi s dng, bo mt truyn thng cc thng tin qun l.

+ C kh nng a ra cc bo co y v r ngha v cc thng tin qun l.

+ Qun l theo thi gian thc v hot ng qun l hng ngy c thc hin mt cch t ng.

+ Mm do trong vic nng cp h thng v c kh nng tng thch vi nhiu cng ngh khc nhau.+ C kh nng lu tr v khi phc cc thng tin qun l.

1.3. Kin trc qun l mng1.3.1. Kin trc qun l mng

Qun l mng gm mt tp cc chc nng iu khin, lp k hoch, lin kt, trin khai v gim st ti nguyn mng. Qun l mng c th c nhn nhn nh mt cu trc gm nhiu lp:

+ Qun l kinh doanh: Qun l kha cnh kinh doanh ca mng v d nh: ngn sch, k hoch v cc tha thun.

+ Qun l dch v: Qun l cc dch v cung cp cho ngi s dng, v d nh: cc dch v cung cp bao gm vic qun l bng thng truy nhp, lu tr d liu v cc ng dng cung cp.

+ Qun l mng: Qun l ton b thit b mng trong mng.

+ Qun l phn t: Qun l mt tp hp thit b mng, v d cc b nh tuyn truy nhp hoc cc h thng qun l thu bao.

+ Qun l phn t mng: Qun l tng thit b n trong mng v d b nh tuyn, chuyn mch, Hub.

Qun l mng c th chia thnh hai chc nng c s: truyn ti thng tin qun l qua h thng v qun l cc phn t thng tin qun l mng. Cc chc nng ny gm cc nhim v khc nhau nh: Gim st, cu hnh, sa li v lp k hoch c thc hin bi nh qun tr hoc nhn vin qun l mng.

1.3.2. C ch qun l mng

C ch qun l mng bao gm cc giao thc qun l mng, cc giao thc qun l mng cung cp cc c ch thu thp, thay i v truyn d liu qun l mng qua mng.

Cc c ch gim st nhm xc nh cc c tnh ca thit b mng, tin trnh gim st bao gm thu thp c v lu tr cc tp con ca d liu . D liu thng c thu thp thng tin qua polling hoc tin trnh gim st gm cc giao thc qun l mng.

X l d liu sau qu trnh thu thp thng tin qun l mng l bc loi b bt cc thng tin d liu khng cn thit i vi tng nhim v qun l. S th hin cc thng tin qun l cho ngi qun l cho php ngi qun l nm bt hiu qu nht cc tnh nng v c tnh mng cn qun l. Mt s k thut biu din d liu thng c s dng di dng k t, th hoc lu .

Ti thi im x l thng tin d liu, rt nhiu cc thng tin cha kp x l c lu tr ti cc vng nh khc nhau. Cc c ch d phng v cp nht lu tr lun c xc nh trc trong cc c ch qun l mng nhm trnh ti a tn tht d liu.

Cc phn tch thi gian thc lun yu cu thi gian hi p ti cc thit b qun l trong khong thi gian ngn. y l iu kin nh i gia s lng c tnh v thit b mng vi lng ti nguyn (kh nng tnh ton, s lng thit b tnh ton, b nh) cn thit h tr cc phn tch.

Thc hin nhim v cu hnh chnh l ci t cc tham s trong mt thit b mang iu hnh v iu khin cc phn t. Cc c ch cu hnh bao gm truy nhp trc tip ti cc thit b, truy nhp t xa v ly cc file cu hnh t cc thit b . D liu cu hnh c thng qua cc cch sau: Cc cu lnh SET ca SNMP, truy nhp qua telnet v giao din dng lnh, truy nhp qua HTTP, truy nhp qua kin trc CORBA, s dng FTP/TFTP ly file cu hnh.

1.4. Tng quan v giao thc SNMP

1.4.1. Cc bi ton gim st cc thit b v ng dng trong h thng mng

Bi ton th 1: Gim st ti nguyn my ch.+ Gi s chng ta c hng ngn my ch chy cc h iu hnh khc nhau. Lm th no c th gim st ti nguyn ca tt c my ch hng gi, kp thi pht hin cc my ch sp b qu ti. Gim st ti nguyn my ch ngha l theo di t l chim dng CPU, dung lng cn li ca cng, t l s dng b nh RAM

+ Chng ta khng th kt ni vo tng my xem v s lng my nhiu v v cc HH khc nhau c cch thc kim tra khc nhau.+ gii quyt vn ny ngi qun tr h thng c th dng mt ng dng SNMP gim st c my ch, n s ly c thng tin t nhiu HH khc nhau.

Hnh 1: Gim st ti nguyn my ch

Bi ton th 2: Gim st lu lng trn cc port ca switch, router.

+ H thng mng c hng ngn thit b mng ca nhiu hng khc nhau, mi thit b c nhiu port. Lm th no gim st lu lng ang truyn qua tt c cc port ca thit b sut 24/24, kp thi pht hin cc port sp qu ti?+ Chng ta cng khng th kt ni vo tng thit b g lnh ly thng tin v thit b ca cc hng khc nhau c lnh khc nhau.

+ gii quyt vn ny ngi qun tr c th dng mt ng dng SNMP gim st lu lng, n s ly c thng tin lu lng ang truyn qua cc thit b ca nhiu hng khc nhau.

Hnh 2: Gim st lu lng thng qua cc port ca switch, router.

Bi ton th 3: H thng t ng cnh bo s c tc thi.

+ H thng c hng ngn thit b mng v chng c th gp nhiu vn trong qu trnh hot ng nh: mt port no b mt tn hiu (port dow), c ai c kt ni (login) vo thit b nhng nhp sai username v password, thit b va mi b khi ng li (restart)Lm th no ngi qun tr bit c s kin n va mi xy ra.+ gii quyt bi ton ny ngi qun tr c th dng ng dng thu thp s kin (event) v cnh bo (warning) bng SNMP, c s nhn cnh bo t tt c cc thit b v hin n ln mn hnh hoc gi email cho ngi qun tr.

Hnh 3: H thng t ng cnh bo s c tc thi1.4.2. Hai phng thc gim st Poll v Alert

Hai giao thc gim st Poll v Alert l 2 phng thc c bn ca cc k thut gim st h thng, nhiu phn mm v giao thc c xy dng da trn 2 phng thc ny, trong c SNMP.

1.4.2.1. Phng thc Poll

Nguyn tt hot ng : Trung tm gim st (manager) s thng xuyn hi thng tin ca cc thit b cn gim st (device). Nu manager khng hi th device khng tr li, nu manager hi th device tr li bng cch hi thng xuyn, manager s lun cp nht c thng tin mi nht t device.

Hnh 4: Hnh minh ha phng thc Poll

1.4.2.2. Phng thc Aler

Nguyn tt hot ng : Mi khi trong Device xy ra mt s kin (event) no th Device s t ng gi thng bo cho Manager, gi l Alert. Manager khng hi thng tin nh k t Device.Device ch gi nhng thng bo mang tnh s kin ch khng gi nhng thng tin thng xuyn thay i, n cng s khng gi Alert nu chng c s kin g xy ra. Chng hn khi mt port down/up th Device s gi cnh bo, cn tng s byte truyn qua port s khng c Device gi i v l thng tin thng xuyn thay i. Mun ly nhng thng tin thng xuyn thay i th Manager phi ch ng i hi Device, tc l phi thc hin phng thc Poll.

Hnh 4: Hnh minh ha phng thc Alert

1.4.2.3. So snh 2 phng thc Poll v Alert

Hai phng thc Poll v Alert l hon ton khc nhau v c ch. Mt ng dng gim st c th s dng Poll hoc Alert, hoc c hai, ty vo yu cu c th trong thc t.

Bng sau so snh nhng im khc bit ca 2 phng thc :

POLLALERT

C th ch ng ly nhng thng tin cn thit t cc i tng mnh quan tm, khng cn ly nhng thng tin khng cn thit t nhng ngun khng quan tm.Tt c nhng event xy ra u c gi v Manager. Manager phi c c ch lc nhng event cn thit, hoc Device phi thit lp c c ch ch gi nhng event cn thit.

C th lp bng trng thi tt c cc thng tin ca Device sau khi poll qua mt lt cc thng tin .Nu khng c event g xy ra th Manager khng bit c trng thi ca Device.

Trong trng hp ng truyn gia Manager v Device xy ra gin on v Device c s thay i, th Manager s khng th cp nht. Tuy nhin khi ng truyn thng sut tr li th Manager s cp nht c thng tin mi nht do n lun lun poll nh k.Khi ng truyn gin on v Device c s thay i th n vn gi Alert cho Manager, nhng Alert ny s khng th n c Manager. Sau mc d ng truyn c thng sut tr li th Manager vn khng th bit c nhng g xy ra.

Ch cn ci t ti Manager tr n tt c cc Device. C th d dng thay i mt Manager khc.Phi ci t tng Device tr n Manager. Khi thay i Manager th phi ci t li trn tt c Device tr v Manager mi.

Nu tn sut poll thp, thi gian ch gia 2 chu k poll di s lm Manager chm cp nht cc thay i ca Device. Ngha l nu thng tin Device thay i nhng vn cha n lt poll k tip th Manager vn gi thng tin c.Ngay khi c s kin xy ra th Device s gi Alert n Manager, do Manager lun lun c thng tin mi nht tc thi.

C th b st cc s kin : khi Device c thay i, sau thay i tr li nh ban u trc khi n lt poll k tip th Manager s khng pht hin c.Manager s c thng bo mi khi c s kin xy ra Device, do Manager khng b st bt k s kin no.

1.4.3. Gii thiu giao thc SNMP

Giao thc l mt tp hp cc th tc m cc bn tham gia cn tun theo c th giao tip c vi nhau. Trong lnh vc thng tin, mt giao thc quy nh cu trc, nh dng ca dng d liu trao i vi nhau v quy nh trnh t, th tc trao i dng d liu . Nu mt bn tham gia gi d liu khng ng nh dng hoc khng theo trnh t th cc bn khc s khng hiu hoc t chi trao i thng tin. SNMP l mt giao thc, do n c nhng quy nh ring m cc thnh phn trong mng phi tun theo.Mt thit b hiu c v hot ng tun theo giao thc SNMP c gi l c h tr SNMP hoc tng thch SNMP. SNMP dng qun l, ngha l c th theo di, c th ly thng tin, c th c thng bo, c th tc ng h thng hot ng nh mun.SNMP dng qun l mng, ngha l n c thit k chy trn nn TCP/IP v qun l cc thit b c ni mng TCP/IP. Cc thit b mng khng nht thit phi l my tnh m c th l switch, router, firewall, ADSL v c mt s phn mm cho php qun tr bng SNMP.SNMP l giao thc n gin, do n c thit k n gin trong cu trc bn tin v th tc hot ng, v cn n gin trong bo mt (ngoi tr SNMP v3). S dng phn mm SNMP, ngi qun tr mng c th qun l, gim st tp trung t xa ton mng ca mnh.a. u im ca thit k SNMP

SNMP c thit k n gin ha qu trnh qun l cc thnh phn trong mng. Nh cc phn mm SNMP c th c pht trin nhanh v tn t chi ph. SNMP c thit k c th m rng cc chc nng qun l, gim st. Khng c gii hn rng SNMP c th qun l c ci g. Khi c mt thit b mi vi cc thuc tnh, tnh nng mi th ngi ta c th thit k custom SNMP phc v cho ring mnh.SNMP c thit k c th hot ng c lp vi cc kin trc v c ch ca cc thit b h tr SNMP. Cc thit b khc nhau c hot ng khc nhau nhng p ng SNMP l ging nhau.

b. Nhc im ca SNMP

Lm tng lu lng ng k.

Khng c s iu khin tng hp ca nhiu ni qun l.

c. Cc phin bn ca SNMPSNMP c 4 phin bn : SNMPvl, SNMPv2c, SNMPv2u v SNMPv3. Cc phin bn ny khc nhau mt cht nh dng bn tin v phng thc hot ng. Hin ti SNMPvl l ph bin nht do c nhiu thit b tng thch nht v c nhiu phn mm h tr nht. Trong khi ch c mt s thit b v phn mm h tr SNMPv3.

1.4.4. Cc thnh phn chnh ca giao thc SNMP

Trong SNMP c 3 vn cn quan tm: Manager, Agent v MIB (Management Information Base). MIB l c s d liu dng phc v cho Management v Agent.

Management l mt server c chy cc chng trnh c th thc hin mt s chc nng qun l mng. Management c th xem nh l NMS (Network Manager Stations). NMS c kh nng thm d v thu thp cc cnh bo t cc Agent trong mng. Cc cnh bo ca Agent l cch m Agent bo vi NMS khi c s c xy ra . Cnh bo ca Agent c gi mt cch khng ng b, khng nm trong vic tr li truy vn ca NMS. MNS da trn nn cc thng tin tr li ca Agent c cc phng n gip mng hot ng hiu qu hn .

Agent l mt phn trong cc chng trnh chy trn cc thit b mng cn qun l. N c th l mt chng trnh c lp, hoc c tch hp vo h iu hnh nh IOS ca Cisco trn Router. Ngy nay, a s cc thit b mng hot ng ti lp IP c ci t SNMP agent. Cc nh sn xut ngy cng mun pht trin cc agent trong cc sn phm ca h, cng vic ca ngi qun tr h thng mng on gin hon. Cc Agent cung cp thng tin cho NMS bng cch lun tr bng cch lu tr cc hot ng khc nhau ca thit b.

MIB l mt c s d liu ca cc i tng qun l c lu tr trn agent. Bt k thng tin no m NMS c th truy cp c u c nh ngha trong MIB. Mt agent c th c nhiu MIB nhng tt c cc agent u c mt loi MIB gi l MIB-II c nh ngha trong RFC 1213. Bt k thit b no h tr SNMP u phi h tr MIB-II. MIB-II nh ngha cc tham s nh tnh trng ca interface (tc ca interface, cc octet gi, cc octet nhn) hoc tham s gn lin vi h thng ( nh v h thng, thng tin lin lc vi h thng).Mc ch chnh ca MIB-II l cung cp cc thng tin qun l theo TCP/IP. Nhng nh sn xut cng nh ngi dng c th nh ngha cc bin MIB ring cho h trong tng tnh hung qun l ca h.1.5. Khi nim giao thc SNMPSNMP gm hai i tng chnh: ngi qun l v ngi phc v (Agent). Agent bao gm c mt phn ca phn mm trong my. SNMP Agent tn ti tt c cc phn ca thit b, tuy nhin thit lp Agent khng cho php lm bt c g cho n khi hi ngi qun l. y l mt chng trnh ring l, ngi qun tr chy chnh my ca mnh hi nhng cu hi n my Agent thu thp thng tin.

Thit lp thng tin c gi l MIB (Management Information Base) c s qun l thng tin. Hu ht mi Agent u c nhng MIB nh cho php ngi qun tr xem nhng gi tin nhp xut ca h thng. Ngoi MIB c bn ny, mi Agent h tr nhng MIB khc nhau cha ng thng tin v mc ch c bit ca n.

Mt giao tip (community) SNMP l mi quan h logic gia ngi phc v SNMP v mt hoc nhiu ngi qun l. Mt community gm c tn v tt tt c nhng thnh vin trong community c cng mt quyn truy cp nh nhau. Thao tc TRAP gi nhng thng tin n trm qun l ( Management Station) khi mt i tng c thay i (cho thy rng vic thay i quan trng n vic phi gi nhng thng bo)

Mc nh chui community cung cp kim tra hay c nhng kh nng th thng xuyn c bit n mc nh s iu khin hay vit nhng chui community th thng xuyn c giu kn. SNMP khai thc nhng thun li ca nhng chui community mc nh cho php ngi tn cng thu thp thng tin v nhng thit b s dng nhng chu community chung, hay ngi tn cng c th thay i cu hnh h thng s dng nhng chui community kn o.

1.6. Cu trc v c im thng tin qun l SMISMI (Structure Management Information) nh ngha mt c cu t chc chung cho thng tin qun l. SMI nhn dng cc kiu d liu trong MIB v ch r cch thc miu t v t tn cc ti nguyn trong MIB. SIM duy tr tnh n gin v kh nng m rng trong MIB, v th MIB ch lu tr nhng loi d liu n gin c th hin thnh 1file (MIB file), v c th biu din thnh 1 cy (MIB tree). SMI khng cung cp cch to hoc truy xut cc cu trc d liu phc tp. Cc MIB s cha cc loi d liu do nh cung cp to ra.

cung cp phng thc tiu chun biu din thng tin qun tr SMI cn nhng cng vic sau:

+ Cung cp k thut tiu chun nh ngha cu trc MIB c bit.+ Cung cp k thut tiu chun nh ngha cc i tng n l, bao gm c php v gi tr mi i tng .

+ Cung cp k thut tiu chun m ha cc gi tr i tng.

S m t cc i tng qun l c SMI thc hin thng qua ngn ng ASN. 1 Vic nh ngha i tng gm 5 trng:

+ Object: Tn i tng

+ Systax: C php cho loi i tng.

+ Definition : Cc nh ngha

+ Truy cp (Access): C th l ch c, c - ghi, khng th truy cp.

+ Trng thi (Status): C th cng ch, ty chn hay khng cn hiu lc1.7. Cc phng thc hot ng ca SNMP

Giao thc SNMP c 5 phng thc hot ng tng ng vi 5 loi bn tin nh sau:

Bn tin/Phng thcM t tc dng

GetRequestManager gi GetRequest cho Agent yu cu Agent cung cp thng tin no da vo ObjectID (trong GetRequest c cha OID).

GetNextRequestManager gi GetNextRequest c cha mt ObjectID cho Agent yu cu cung cp thng tin nm k tip ObjectID trong MIB.

SetRequestManager gi SetRequest cho Agent t gi tr cho i tng ca Agent da vo ObjectID.

GetResponseAgent gi GetResponse cho Manager tr li khi nhn c GetRequest/GetNextRequest.

TrapAgent t ng gi Trap cho Manager khi c mt s kin xy ra i vi mt Object no trong Agent.

Mi bn tin u c cha OID cho bit Object mang trong n l g. OID trong GetRequest cho bit n mun ly thng tin ca Object no. OID trong GetResponse cho bit n mang gi tr ca Object no.OID trong SetRequest ch ra n mun thit lp gi tr cho Object no. OID trong Trap ch ra n thng bo s kin xy ra i vi Object no.

Hnh 5 : Minh ha cc phng thc ca SNMPv1

1.8. Cc c ch bo mt ca SNMPMt SNMP manager station c th qun l/ gim st nhiu SNMP element, thng qua hot ng gi request v nhn trap. Tuy nhin mt SNMP element c th c cu hnh ch cho php cc SNMP management station no c php qun l/gim st mnh. C ch bo mt n gin ny gm c : community string, view v SNMP access control list. Community string l mt chui k t c ci t ging nhau trn c SNMP manager v SNMP agent, ng vai tr nh mt khu gia 2 bn khi trao i d liu. Community string c 3 loi: Read-community, Write-Community v Trap-Community.Khi manager gi GetRequest, GetNextRequest n agent th trong bn tin gi i c cha Read- Community. Khi agent nhn c bn tin request th n s so snh Read-community do manager gi v Read-community m n c cit. Nu 2 chui ny ging nhau, agent s tr li, nu 2 chui ny khc nhau, agent s khng tr li.

Write-Community c dng trong bn tin SetRequest. Agent ch chp nhn thay i d liu khi write- community 2 bn ging nhau.

Trap-community nm trong bn tin trap ca trap sender gi cho trap receiver. Trap receiver ch nhn v lu tr bn tin trap ch khi trap-community 2 bn ging nhau, tuy nhin cng c nhiu trap receiver c cu hnh nhn tt c bn tin trap m khng quan tm n trap-community.Community string c 3 loi nh trn nhng cng mt loi c th c nhiu string khc nhau. Ngha l mt agent c th khai bo nhiu read-community, nhiu write-community. Trn hu ht h thng, read-community mc nh l "public", write-community mc nh l "private" v trap-community mc nh l "public".Community string ch l chui k t dng cleartext, do hon ton c th b nghe ln khi truyn trn mng. Hn na, cc community mc nh thng l "public" v "private" nn nu ngi qun tr khng thay i th chng c th d dng b d ra. Khi community string trong mng b l, mt ngi dng bnh thng ti mt my tnh no trong mng c th qun l/gim st ton b cc device c cng community m khng c s cho php ca ngi qun tr.

View

Khi manager c read-community th n c th c ton b OID ca agent. Tuy nhin agent c th quy nh ch cho php c mt s OID c lin quan nhau, tc l ch c c mt phn ca MIB. Tp con ca MIB ny gi l view, trn agent c th nh ngha nhiu view. Mt view phi gn lin vi mt community string. Ty vo community string nhn c l g m agent x l trn view tng ng.

SNMP access control list.

Khi manager gi khng ng community hoc khi OID cn ly li khng nm trong view cho php th agent s khng tr li. Tuy nhin khi community b l th mt manager no vn request c thng tin. ngn chn hon ton cc SNMP manager khng c php, ngi qun tr c th dng n SNMP access control list (ACL).

SNMP ACL l mt danh sch cc a ch IP c php qun l/gim st agent, n ch p dng ring cho giao thc SNMP v c ci trn agent. Nu mt manager c IP khng c php trong ACL gi request th agent s khng x l, d request c community string l ng.a s cc thit b tng thch SNMP u cho php thit lp SNMP ACL.

1.9. Cu trc bn tin SNMPSNMP chy trn nn UDP. Cu trc ca mt bn tin SNMP bao gm : version, community v data.

Hnh 6 : Cu trc bn tin SNMP

Version: v1=0, v2c=1, v2u=2, v3=0

Phn Data trong bn tin SNMP gi l PDU (Protocol Data Unit). SNMPv1 c 5 phng thc hot ng tng ng 5 loi PDU. Tuy nhin ch c 2 loi nh dng bn tin l PDU v Trap-PDU, trong cc bn tin Get, GetNext, Set, GetResponse c cng nh dng l PDU, cn bn tin Trap c nh dng l Trap-PDU.CHNG 2: TRIN KHAI CI T V MT S TNH NNG

GIM ST V QUN TR MNG BNG PHN MM

QUEST FREE NETWORK TOOLS

2.1. Gii thiu v phn mm Quest free network tool.

- Quest Free Network Tools gim st cc hot ng ca h thng mng. Vi cng c ny c th p dng trn mi dng network a dng khc nhau v gip khc phc mi li kt ni ph bin ch vi vi c click chut n gin. C th ni Quest Free Network Tools l mt cng c c o cho php qun tr vin tin hnh cng vic gim st an ninh mng mt cch nhanh chng v n gin. Chng trnh gip khoanh vng v xc nh cc on li mng ch trong thi gian ngn.

-Quest Free Network Tools c th qun l trn nhiu ni dung kt ni khc nhau nh: cu hnh Cisco, Switch Port Mapper, NetFlow Listener ....Nh , bn c th nm bt ton din cc hot ng ca h thng v tin hnh khc phc mt cch m bo.

-c bit, Quest Free Network Tools h tr cc tnh nng kt ni my ch TFTP, DNS, SNMP, WMI, Syslog ...thng minh. Bn cnh , chng trnh cn gip bn chuyn i c s d liu mt cch an ton v m bo thng qua trnh iu khin SQL v Active Directory.

-Quest Free Network Tools h tr ti u ha v m rng thit b truy cp h thng mng mt cch an ton. Hn th na, y cn l mt chng trnh cc k n gin vi thit k giao din n nht gm nhiu tnh nng cng lc gip bn d dng thao tc v s dng.

2.2. Cc tnh nng chnh ca Quest Free Network Tools:- Cho php gim st an ninh mng mt cch nhanh chng v n gin.- Gip bn khoanh vng v xc nh cc on li mng ch trong thi gian ngn.- C th qun l trn nhiu ni dung kt ni khc nhau nh: cu hnh Cisco, Switch Port Mapper, NetFlow Listener ....- H tr kt ni my ch TFTP, DNS, SNMP, WMI, Syslog ...- Gip chuyn i c s d liu mt cch an ton v m bo thng qua trnh iu khin SQL v Active Directory.- Ti u ha v m rng thit b truy cp h thng mng mt cch an ton.- n gin, giao din ng nht.

2.3. Yu cu h thng

- Quest Free Network Tools l mt ng dng nh, c th chy trn hu nh bt k my tnh da trn Windows. Nh mt nguyn tc chung, bng di y cung cp cho bn vi cc phn cng v phn mm h thng cc yu cu ti thiu chy Quest Free Network Tools.

Yu cu h thngCu hnh ti thiu

H iu hnhH iu hnh 32-bit hoc 64-bit :

Windows 2003 SP1 hoc mi hn

Windows XP SP2 hoc mi hn

Windows Vista SP1 (mi phin bn)

Tc x l CPUPentium III hoc cao hn.

B nh256MB hoc nhiu hn.

Khng gian cng40MB hoc nhiu hn

2.4. Ci t Mt s lu : Trc khi ci t Quest Free Network Tools phi ci .Net Framework phin bn 2.0 hoc cao hn. Qu trnh ci t :

Bc 1: Click chut phi vo File ci t, chy bng quyn Administrator

Bc 2: Chn Next

Bc3: Tch vo I accept the term in the license agreement => Next

Bc 4: Tch vo Anyone who uses this computer (all users)=>Next

Bc 5 : Chn ng dn lu ci t phn mm

Bc 6: Chn Install ci t phn mm

Bc 7: Nhn Finish hon tt ci t phn mm

Mt s chc nng ca phn mm gim st h thng mng Quest Free Network Tools

Chc nng tm kim : y chng ta c th tm kim theo bn windows hoc cc phn c ci t trn my client

DNS Audit

Cng c DNS Audit hin th tt c cc my ang hot ng trong h thng mng

Enhanced Ping

Cng c Enhanced Ping lin tc ng thi gian chy p ng v xut d liu theo yu cu. Cc bo co cho Enhanced Ping ng k thi gian phn ng hin ti v thi gian p ng trung bnh chy trong mili giy cng nh tc hin ti ca gi tin b mt.

Graphical Ping

MAC Scan

Cng c MAC Scan hin th tt c cc a ch MAC ca cc my ang hot ng trong h thng mng

SNMP Scan

Port Scan

Hin th tt c cc port ang m v cc port ng ca tt c cc my trong h thng mng

SNMP Walk

Hin th tt c cc thng tin v my clientChng ta cng c th tm kim thng tin theo OID

Gim st ti nguyn h thng mng y chng ta c th tm kim theo bn windows hoc software c ci t trn client.

KT LUN1. Kt lun :

Sau mt thi gian thc hin, nhm hon thnh n v t c mt s kt qu nht nh. Trong n mn hc ny, nhm em nghin cu tm hiu v giao thc gim st mng SNMP, cc phng thc gim st mng, u im, nhc im trong thit k ca SNMP v tm hiu qun l h thng mng vi phn mm Quest Free Network Tools, trong qu trnh nghin cu c s ch bo tn tnh ca thy gio b mn v s nhit tnh ca thnh vin trong nhm nn nhm hon thnh n ny, song bn cnh th vn cn mt s tn ti.2. Kt qu t c

V l thuyt :

Nhm tm hiu c tng quan v giao thc SNMP, cc phng thc gim st mng, u im, nhc im trong thit k ca SNMP v tm hiu qun l h thng mng vi phn mm Quest Free Network Tools V thc hnh :

Trin khai h thng gim st v qun tr mng vi phn mm Quest Free Network Tools trn m hnh gi lp, thc hin mt s chc nng gim st c bn.

3. Hng pht trin

Da vo kt qu nghin cu trn c th xy dng phn mm qun tr h thng mng thng qua giao thc SNMP.

Kt hp vi vic nghin cu mt s gii php an ninh c v phn cng v phn mm khc c th xy dng mt h thng mng vi an ton v d liu v bo mt cao

4. Li cm n

Nhm em xin chn thnh cm n thy Nguyn V cng cc thy c trong khoa Khoa hc my tnh gip em hon thnh n ny.

TI LIU THAM KHO[1] SNMP ton tp, Dip Thanh Nguyn, 2010.[2] Slide Qun l h thng mng, Ths.Nguyn V.[3 Quest Free Network Tools Help, Index.[4] http://vi.wikipedia.org/[5] http://net-snmp.sourceforge.net/

SVTH: Xun Pha-Vn Ha

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