Hauv kev lag luam network thiab kev saib xyuas, nws yog ib qho teeb meem tab sis teeb meem uas cov khoom siv tsis tuaj yeem Ping tom qab txuas ncaj qha. Rau ob qho tib si pib thiab paub txog engineers, feem ntau yuav tsum tau pib ntawm ntau theem thiab tshuaj xyuas qhov ua tau. Kab lus no rhuav tshem cov kauj ruam daws teeb meem los pab koj sai nrhiav lub hauv paus ntawm qhov teeb meem thiab kho nws. Cov txheej txheem no yog siv tau thiab siv tau hauv ob qho tib si hauv tsev network thiab chaw lag luam ib puag ncig. Peb yuav taug kev koj los ntawm qhov kev sib tw no ib kauj ruam dhau los, los ntawm cov tshev yooj yim mus rau kev kuaj xyuas qib siab.
1. Txheeb xyuas qhov kev sib txuas ntawm lub cev kom paub tseeb tias lub teeb liab ua haujlwm
Lub hauv paus ntawm kev sib txuas lus network yog kev sib txuas ntawm lub cev. Yog tias lub cuab yeej ua tsis tiav Ping tom qab kev sib txuas ncaj qha, thawj kauj ruam yog los xyuas tias cov txheej txheem lub cev ua haujlwm. Nov yog cov kauj ruam:
Paub meej tias Network Cable Txuas:Xyuas seb lub network cable yog ntsaws rau hauv nruj thiab seb lub network cable interface puas xoob. Yog tias siv cov kab ncaj nraim, xyuas kom cov cable ua raws li TIA / EIA-568-B tus qauv (Common Direct Cable Standard). Yog tias koj muaj cov cuab yeej qub, koj yuav tsum tau hla cov kab (TIA / EIA-568-A) vim tias qee cov khoom siv qub tsis txhawb kev hloov pauv tsis siv neeg MDI / MDIX.
Txheeb xyuas qhov zoo ntawm Network Cable:tsis zoo los yog ntev network cable yuav ua rau cov teeb liab attenuation. Standard network cable ntev yuav tsum tau tswj nyob rau hauv 100 meters. Yog hais tias lub cable ntev dhau lawm los yog muaj kev puas tsuaj (piv txwv li, tawg los yog flattened), nws raug nquahu kom hloov nws nrog lub siab zoo cable thiab rov kuaj dua.
Saib Cov Ntsuas Ntaus Ntaus:Feem ntau cov khoom siv hauv network (xws li cov keyboards, routers, network cards) muaj cov cim qhia txog kev sib txuas. Nquag, lub teeb yuav teeb (ntsuab lossis txiv kab ntxwv) tom qab kev sib txuas, thiab tej zaum yuav muaj flicker los qhia cov ntaub ntawv xa mus. Yog hais tias qhov taw qhia tsis teeb, nws yuav muaj teeb meem nrog lub network cable, lub interface tawg, lossis lub cuab yeej tsis siv.
Xeem Chaw nres nkoj:Txuas lub network cable mus rau lwm qhov chaw nres nkoj ntawm lub cuab yeej kom tshem tawm qhov ua tau ntawm qhov chaw nres nkoj puas. Yog tias muaj, koj tuaj yeem siv lub network cable tester los xyuas qhov kev sib txuas ntawm lub network cable kom paub meej tias txhua khub ntawm cov xov hlau raug txiav kom raug.
Kev sib txuas ntawm lub cev yog thawj kauj ruam hauv kev sib txuas lus hauv network, thiab peb yuav tsum xyuas kom meej tias tsis muaj teeb meem ntawm txheej txheej no ua ntej peb tuaj yeem tshawb xyuas qhov ua rau qib siab dua.
2. Tshawb xyuas STP Status ntawm lub cuab yeej kom paub tseeb tias qhov chaw nres nkoj tsis muaj neeg xiam
Yog tias koj tsis tuaj yeem Ping txawm tias muaj kev sib txuas ntawm lub cev ib txwm muaj, tej zaum yuav muaj teeb meem nrog lub cuab yeej txuas-txheej txheej raws tu qauv. Ib qho laj thawj yog Spanning Tree Protocol (STP).
Nkag siab lub luag haujlwm ntawm STP:STP (Spanning Tree Protocol) yog siv los tiv thaiv qhov tshwm sim ntawm lub voj voog hauv lub network. Yog tias ib lub cuab yeej pom lub voj, STP tso qee qhov chaw nres nkoj hauv Lub Xeev Thaiv, tiv thaiv lawv ntawm kev xa cov ntaub ntawv.
Kos qhov chaw nres nkoj:Nkag mus rau hauv koj lub cuab yeej CLI (Command Line interface) lossis Web admin interface kom pom tias qhov chaw nres nkoj nyob hauv lub xeev "Forwarding". Nyob rau hauv rooj plaub ntawm Cisco hloov, STP raws li txoj cai tuaj yeem pom siv cov lus txib qhia spat-ntoo. Yog tias qhov chaw nres nkoj pom tias yog "Blocking", STP tab tom thaiv kev sib txuas lus ntawm qhov chaw nres nkoj.
Kev daws:
Disable STP ib ntus:Hauv ib puag ncig kev sim, nws muaj peev xwm tua STP ib ntus (piv txwv li, tsis muaj spath-ntoo vlan 1), tab sis qhov no tsis pom zoo hauv kev tsim khoom vim nws yuav ua rau muaj cua daj cua dub.
Qhib PortFast:Yog tias lub cuab yeej txhawb nqa nws, PortFast muaj nuj nqi tuaj yeem qhib rau ntawm qhov chaw nres nkoj (cov lus txib xws li spath-ntoo portfast), tso cai rau lub chaw nres nkoj hla STP mloog thiab kawm theem thiab ncaj qha nkag mus rau lub xeev xa mus.
Tshawb xyuas Loops:Yog tias STP thaiv yog tshwm sim los ntawm qhov muaj nyob ntawm lub voj voog hauv lub network, ntxiv mus xyuas lub network topology kom pom thiab tawg lub voj.
Cov teeb meem STP muaj nyob rau hauv kev lag luam tes hauj lwm, tshwj xeeb tshaj yog nyob rau hauv ntau qhov chaw hloov. Yog tias koj muaj lub network me me, koj tuaj yeem hla cov kauj ruam no rau tam sim no, tab sis nkag siab tias STP ua haujlwm li cas tuaj yeem mus ntev hauv kev daws teeb meem yav tom ntej.
3. Xyuas seb ARP puas ua haujlwm kom paub tseeb tias qhov chaw nyob MAC raug kho kom raug
Thaum cov txheej txheem txuas yog qhov qub, mus rau txheej txheej network los xyuas. Cov lus txib Ping cia siab rau ICMP raws tu qauv, uas ua ntej daws cov phiaj xwm IP chaw nyob rau MAC chaw nyob ntawm Chaw Nyob Kev daws teeb meem (ARP). Yog tias ARP daws teeb meem ua tsis tiav, Ping yuav ua tsis tiav.
Tshawb xyuas ARP lub rooj: Txheeb xyuas ARP lub rooj ntawm lub cuab yeej kom paub meej tias MAC chaw nyob ntawm lub hom phiaj tau daws tiav. Hauv Windows, piv txwv li, koj tuaj yeem saib ARP cache los ntawm qhib kab hais kom ua thiab ntaus arp-a. Yog tias tsis muaj qhov chaw nyob MAC rau tus IP chaw nyob, ARP daws teeb meem ua tsis tiav.
Manually Testing ARP:Sim xa ARP thov manually. Piv txwv li, ntawm Windows koj tuaj yeem siv ping hais kom ua rau qhov kev thov ARP, lossis siv cov cuab yeej ncaj qha xws li arping (ntawm Linux systems). Yog tias tsis muaj lus teb rau ARP qhov kev thov, cov laj thawj tshwm sim muaj xws li:
Firewall Blocking:Kev thov ARP raug thaiv los ntawm firewall ntawm qee cov khoom siv. Txheeb xyuas qhov chaw firewall ntawm lub hom phiaj ntaus ntawv thiab sim dua tom qab ib ntus tua lub firewall.
IP Sib tsoo:ARP daws teeb meem yuav ua tsis tau yog tias muaj kev sib tsoo IP chaw nyob hauv lub network. Siv lub cuab yeej xws li Wireshark txhawm rau ntes cov pob ntawv thiab saib seb puas muaj ntau qhov chaw nyob MAC teb rau tib tus IP.
Kev daws:
Rho tawm Arpcache (Windows: netsh interface ip rho tawm arpcache; Linux: ip-ss neigh flush tag nrho) thiab tom qab ntawd Ping dua.
Xyuas kom tseeb tias tus IP chaw nyob ntawm ob lub cuab yeej nyob hauv tib lub subnet thiab tias lub npog ntsej muag subnet yog tib yam (saib cov kauj ruam tom ntej kom paub meej).
Cov teeb meem ARP feem ntau cuam tshuam nrog kev teeb tsa ntawm lub network txheej, thiab nws yuav siv sijhawm ntev rau kev daws teeb meem kom paub tseeb tias txhua yam ua haujlwm.
4. Txheeb xyuas IP Chaw Nyob thiab Subnet Configuration kom paub meej txog kev sib txuas lus
Cov teeb meem ntawm txheej txheej network feem ntau yog qhov ua txhaum loj rau Ping ua tsis tiav. Kev teeb tsa IP tsis raug thiab subnets ua rau cov khoom siv tsis sib txuas lus. Nov yog cov kauj ruam:
Paub meej IP chaw nyob:Xyuas seb tus IP chaw nyob ntawm ob lub cuab yeej puas nyob hauv tib lub subnet. Piv txwv li, ntaus ntawv A muaj IP ntawm 192.168.1.10 thiab subnet npog ntawm 255.255.255.0. Ntaus B muaj tus IP ntawm 192.168.1.20 thiab tib lub ntsej muag subnet. Ob lub ips nyob rau tib lub subnet (192.168.1.0/24) thiab tuaj yeem sib txuas lus theoretical. Yog tias ntaus ntawv B muaj tus IP ntawm 192.168.2.20, nws tsis nyob ntawm tib lub subnet thiab Ping yuav ua tsis tiav.
Tshawb xyuas Subnet Masks:Cov qhov ncauj qhov ntswg subnet tsis sib haum kuj tuaj yeem ua rau kev sib txuas lus tsis tiav. Piv txwv li, ntaus ntawv A muaj daim npog qhov ncauj ntawm 255.255.255.0 thiab ntaus B muaj daim npog qhov ncauj ntawm 255.255.0.0, uas yuav ua rau muaj kev cuam tshuam kev sib txuas lus vim lawv qhov sib txawv ntawm kev nkag siab ntawm subnet Scope. Xyuas kom tseeb tias lub qhov ncauj qhov ntswg subnet yog tib yam rau ob qho tib si.
Xyuas Gateway Settings:Cov khoom siv txuas ncaj qha feem ntau tsis xav tau lub rooj vag, tab sis lub rooj vag tsis raug cai tuaj yeem ua rau cov pob ntawv xa mus tsis raug. Xyuas kom tseeb tias lub rooj vag rau ob lub cuab yeej tau teeb tsa tsis tau teeb tsa lossis taw qhia rau qhov chaw nyob kom raug.
Kev daws:
Hloov kho qhov chaw nyob IP lossis lub npog ntsej muag subnet kom ntseeg tau tias ob lub cuab yeej nyob hauv tib lub subnet. Lov tes taw qhov rooj tsis tsim nyog los yog teeb tsa lawv mus rau tus nqi qub (0.0.0.0).
IP configuration yog qhov tseem ceeb ntawm kev sib txuas lus hauv network, yog li nws yog ib qho tseem ceeb uas yuav tsum tau kuaj xyuas ob zaug kom ntseeg tau tias tsis muaj dab tsi ploj lawm.
5. Txheeb xyuas cov ICMP pob ntawv xa thiab tau txais los xyuas kom meej tias Txoj Cai Tsis Muaj Kev Ua Phem
Ping hais kom ua nyob rau hauv Internet Control Messaging Protocol (ICMP). Yog tias cov pob ntawv ICMP raug cuam tshuam lossis xiam oob qhab, Ping yuav tsis ua tiav.
Tshawb xyuas koj cov cai Firewall:Ntau lub cuab yeej muaj firewalls enabled los ntawm lub neej ntawd, uas yuav thaiv ICMP thov. Hauv Windows, piv txwv li, txheeb xyuas "Windows Defender Firewall" kom paub tseeb tias ICMPv4-In txoj cai raug tso cai. Linux systems tshawb xyuas iptables txoj cai (iptables -L) kom paub tseeb tias ICMP tsis raug thaiv.
Tshawb xyuas Cov Cai Tswj Khoom Siv:Qee lub routers lossis keyboards lov tes taw ICMP cov lus teb los tiv thaiv kev luam. Nkag mus rau hauv lub cuab yeej tswj kev tshuaj ntsuam kom paub tseeb tias ICMP yog neeg xiam.
Packet Capture Analysis:Siv lub cuab yeej xws li Wireshark lossisMylinking Network KaisthiabMylinking Network Packet Brokerstxhawm rau ntes cov pob ntawv kom pom seb puas tau thov ICMP thiab yog tias muaj lus teb. Yog tias qhov kev thov tau ua tab sis tsis muaj lus teb, qhov teeb meem yuav nyob ntawm lub hom phiaj ntaus ntawv. Yog tias tsis muaj kev thov, qhov teeb meem yuav nyob ntawm lub tshuab hauv zos.
Kev daws:
(Windows: netsh advfirewall teeb tsa tag nrho cov ntaub ntawv hauv xeev; Linux: iptables -F) txhawm rau kuaj seb Ping puas rov qab los li qub.Ua kom ICMP cov lus teb ntawm lub cuab yeej (piv txwv li, Cisco ntaus ntawv: ip icmp ncha- teb).
ICMP cov teeb meem feem ntau cuam tshuam nrog kev ruaj ntseg cov cai, uas yuav tsum muaj kev sib pauv ntawm kev ruaj ntseg thiab kev sib txuas.
6. Txheeb xyuas seb daim ntawv ntim khoom puas raug los xyuas kom meej tias tsis muaj qhov txawv txav hauv Cov Txheej Txheem Txheej Txheem
Yog tias txhua yam ua tau zoo thiab koj tseem tsis tuaj yeem Ping, koj yuav tsum tau nkag mus rau hauv cov txheej txheem txheej txheem txhawm rau txheeb xyuas tias pob ntawv yog nyob rau hauv qhov tseeb.
Capture thiab Analyze Packets:
Siv Wireshark los ntes ICMP pob ntawv thiab xyuas cov hauv qab no:
- Hom thiab Code ntawm ICMP Thov yog qhov tseeb (Echo Thov yuav tsum yog Hom 8, Code 0).
- Seb qhov chaw thiab qhov chaw ips yog qhov tseeb.
- Seb puas muaj qhov txawv txav TTL (Lub Sijhawm Ua Neej Nyob) qhov tseem ceeb uas tuaj yeem ua rau cov pob ntawv poob rau ib nrab.
Xyuas MTU Settings:Yog hais tias qhov siab tshaj plaws kis tau tus mob Unit (MTU) Settings tsis zoo ib yam, pob ntawv fragmentation yuav ua tsis tau. Lub neej ntawd MTU yog 1500 bytes, tab sis qee cov khoom siv yuav raug teeb tsa nrog cov nqi me me. Kuaj fragmentation nrog cov lus txib ping-fl 1472 lub hom phiaj IP (Windows). Yog hais tias sharding yog prompted tab sis lub Do not sharding (DF) chij yog teem, lub MTU tsis phim.
Kev daws:
Kho tus nqi MTU (Windows: netsh interface ipv4 teeb subinterface "Ethernet" mtu = 1400 khw = pheej).
Xyuas kom meej tias MTU ntawm ob lub cuab yeej yog tib yam.
Cov txheej txheem pawg teeb meem yog qhov nyuaj dua, nws tau pom tias qhov kev soj ntsuam tob tob yog nqa tawm tom qab qhov kev tshawb nrhiav yooj yim tsis muaj txiaj ntsig.
7. Sau cov ntaub ntawv thiab nrhiav kev txhawb nqa
Yog tias cov kauj ruam saum toj no tsis daws qhov teeb meem, tej zaum koj yuav xav tau ntxiv cov ntaub ntawv thiab nrhiav kev txhawb nqa.
Log:Sau cov ntaub ntawv teev tseg ntawm lub cuab yeej (syslog ntawm router / hloov, syslog ntawm PC) thiab saib seb puas muaj qhov yuam kev.
Hu rau tus neeg tsim khoom:Yog tias cov cuab yeej yog cov khoom lag luam xws liMylinking(Network Taps, Network Packet BrokersthiabInline Bypass), Cisco(Router/Switch), Huawei(Router/Switch), koj tuaj yeem tiv tauj rau kev txhawb nqa ntawm cov chaw tsim khoom los muab cov ncauj lus kom ntxaws soj ntsuam cov kauj ruam thiab cov cav.
Leveraging the Community:Tshaj tawm ntawm cov rooj sab laj kev lag luam (piv txwv li, Stack Overflow, Cisco Community) rau kev pab, muab cov ncauj lus kom ntxaws network topology thiab cov ntaub ntawv teeb tsa.
Kev sib txuas ncaj qha rau lub network ntaus ntawv uas tsis ua rau Ping yuav zoo li yooj yim, tab sis qhov tseeb nws yuav cuam tshuam ntau yam teeb meem ntawm lub cev txheej, txuas txheej, txheej txheej network, thiab txawm tias cov txheej txheem txheej txheem. Feem ntau cov teeb meem tuaj yeem daws tau los ntawm kev ua raws li xya kauj ruam no, txij li theem pib mus rau qib siab. Txawm hais tias nws tab tom kuaj xyuas lub network cable, kho STP, txheeb xyuas ARP, lossis ua kom zoo dua IP kev teeb tsa thiab ICMP txoj cai, txhua kauj ruam yuav tsum tau saib xyuas thiab ua siab ntev. Kuv vam tias phau ntawv qhia no yuav ua rau koj paub meej txog yuav ua li cas rau koj qhov teeb meem hauv Is Taws Nem, yog li koj yuav tsis tsis meej pem yog tias koj ntsib teeb meem zoo sib xws.
Post lub sij hawm: May-09-2025
