LFCA: Koyi Matakan Shirya Matsala na hanyar sadarwa - Sashe na 12
Lokacin da tsarin ya gamu da lamuran, kamar yadda wani lokaci zasu fuskanta, kana bukatar sanin hanyarka game da matsalar kuma dawo dasu yadda suke da aiki. A cikin wannan ɓangaren, muna mai da hankali kan ƙwarewar magance matsalar hanyar sadarwa wanda duk mai gudanar da tsarin Linux yakamata ya samu.
Asali na Fahimtar Matsalar hanyar sadarwa
A mafi yawan lokuta, akwai tazara mai yawa tsakanin admins na cibiyar sadarwa da sysadmins. Sysadmins da ke da karancin gani na cibiyar sadarwa galibi za su zargi masu kula da hanyoyin sadarwa saboda rashin aiki da kuma karancin lokaci yayin da admins din masu kula da hanyoyin sadarwa ba za su samu isassun ilimin saba ba sau da yawa za su juya laifin sysadmins na gazawar na'urar. Koyaya, wasan zargi ba ya taimakawa warware matsaloli kuma a cikin yanayin aiki, wannan na iya ɓata dangantaka tsakanin abokan aiki.
A matsayinka na sysadmin, samun cikakkiyar fahimta game da matsalar matsala ta hanyar sadarwa zai taimaka warware batutuwan da sauri kuma zai taimaka inganta yanayin aiki tare. Wannan dalilin ne yasa muka sanya wannan sashin don haskaka wasu daga cikin muhimman hanyoyin magance matsala na cibiyar sadarwa da zasu zo da sauki yayin bincikar matsalolin da suka shafi hanyar sadarwa.
A cikin maudu'inmu na baya na TCP/IP ƙirar ƙirar fahimta wacce ke nuna watsa bayanai a cikin kwamfuta da ladabi waɗanda ake samu a cikin kowane layi.
Wani samfurin mahimmanci mai mahimmanci shine samfurin OSI (Open Systems Interconnection) samfurin. Yana da tsarin 7 na TCP/IP wanda ke lalata tsarin sadarwar, da kuma ayyukan sarrafa kwamfuta kamar kowane layi.
A cikin samfurin OSI, waɗannan ayyukan an kasu kashi zuwa matakan da ke zuwa daga ƙasa. Mai shimfiɗa ta jiki, Mai haɗa bayanan data, Mai shimfida hanyar sadarwa, Mai shimfida hanya, Salon Zama. Gabatarwar Mai Gabatarwa, da ƙarshe Layer Aikace-aikace a saman sosai.
Ba shi yiwuwa a yi magana game da gyara matsala ta hanyar sadarwa ba tare da yin nuni ga ƙirar OSI ba. A saboda wannan dalili, za mu bi ku ta kowane layi mu gano hanyoyin ladabi da yawa da aka yi amfani da su da kuma yadda za a magance lamuran da ke tattare da kowane layi.
Wannan wataƙila ɗayan ɗayan matakan da ba a kula da su ba, duk da haka yana ɗaya daga cikin mahimman matakan da ake buƙata don kowane hanyar sadarwa ya gudana. Launin Jiki ya ƙunshi abubuwan sadarwar PC na PC na PC kamar katunan cibiyar sadarwa, igiyoyin Ethernet, zaren gani, da dai sauransu Yawancin matsaloli suna farawa a nan kuma galibi ana haifar da su ne:
- Cire hanyar sadarwa/ethernet kebul
- Cibiyoyin sadarwa/layin ethernet da aka lalata
- katin network da ya ɓace ko lalacewa
A cikin wannan shimfidar, tambayoyin da zasu zo tunani shine:
- "Shin an haɗa kebul na hanyar sadarwa?"
- "Shin hanyar sadarwar zahiri tana haɗuwa?"
- "Kuna da adireshin IP?"
- “Shin zaku iya ping na tsoffin ƙofa ta IP?”
- “Shin za ku iya ping na uwar garken ku na DNS?”
Don bincika matsayin hanyoyin sadarwar ku, gudanar da umarnin ip:
$ ip link show
Daga abubuwan da aka fitar a sama, Muna da musaya 2. Hanyar farko - lo - shine adireshin madauki kuma yawanci ba'ayi amfani dashi. Hanyar sadarwar aiki mai aiki wanda ke ba da haɗin kai ga cibiyar sadarwar da intanet shine enp0s3 kewayawa. Muna iya gani daga fitowar cewa yanayin ƙirar yana UP.
Idan hanyar sadarwar yanar gizo tayi kasa, zaka ga yadda ake fitar da jihar.
Idan haka ne, zaku iya kawo haɗin sama ta amfani da umarnin:
$ sudo ip link set enp0s3 up
A madadin, zaku iya gudanar da umarnin ifconfig wanda aka nuna a ƙasa.
$ sudo ifconfig enp0s3 up $ ip link show
Kawai don tabbatar da cewa kwamfutarka ta zaɓi adireshin IP daga na'ura mai ba da hanya tsakanin hanyoyin sadarwa ko sabar DHCP, gudanar da umarnin ifconfig.
$ ifconfig
Adireshin IPv4 an kayyade shi ta hanyar shigarwar shigarwar kamar yadda aka nuna. Misali, adireshin IP na wannan tsarin shine 192.168.2.104 tare da subnet ko netmask na 255.255.255.0.
$ ifconfig
A madadin, zaku iya gudanar da umarnin adireshin ip kamar haka don bincika adireshin IP ɗin ku na tsarin.
$ ip address
Don bincika adireshin IP na ƙofar tsoho, gudanar da umurnin:
$ ip route | grep default
Adireshin IP na ƙofar tsoho, wanda a mafi yawan lokuta shine sabar DHCP ko na'ura mai ba da hanya tsakanin hanyoyin sadarwa, ana nuna kamar yadda aka nuna a ƙasa. A cikin hanyar sadarwar IP, ya kamata ku sami damar yin ping ta tsoffin ƙofa.
Don bincika sabobin DNS da kuke amfani da su, gudanar da umarni mai zuwa akan tsarin tsarin.
$ systemd-resolve --status
Hanya mafi kyau don bincika sabobin DNS da ake amfani dasu shine don gudanar da nmcli umurnin da aka nuna
$ ( nmcli dev list || nmcli dev show ) 2>/dev/null | grep DNS
Kamar yadda kuka lura, babban ɓangaren matsalar gyara cibiyar sadarwa yana faruwa anan.
Ainihin, layin haɗin bayanan yana ƙayyade tsarin bayanai akan hanyar sadarwa. Anan ne ake sadar da jigon bayanan bayanai tsakanin runduna. Babban yarjejeniya a cikin wannan layin shine ARP (Yarjejeniyar Magance Adireshin).
ARP ce ke da alhakin gano adiresoshin-hanyar haɗin yanar gizo kuma suna yin taswira na adiresoshin IPv4 akan layin 3 zuwa adiresoshin MAC. Yawancin lokaci, lokacin da mai masauki ya tuntuɓi ƙofar tsoho, dama ita ce ta riga ta sami IP na mai watsa shiri, amma ba adiresoshin MAC ba.
Yarjejeniyar ARP ta haɗar da rata tsakanin Layer 3 da Layer 2 ta hanyar fassara adiresoshin IPv4 32-bit 32 a kan Layer 3 zuwa 48-bit MAC adireshin a kan Layer 2 da kuma akasin haka.
Lokacin da PC ta haɗu da cibiyar sadarwar LAN, na'ura mai ba da hanya tsakanin hanyoyin sadarwa (ƙofar da ta gabata) tana sanya masa adireshin IP don ganewa. Lokacin da wani mai masaukin baki ya aika fakiti na bayanai wanda aka kaddara zuwa PC din zuwa kofar da aka saba, sai na'ura mai ba da hanya tsakanin hanyoyin sadarwa ta nemi ARP da ta nemi adireshin MAC da ke tare da adireshin IP.
Kowane tsarin yana da nasa teburin ARP. Don bincika teburin ARP ɗinku, gudanar da umurnin:
$ ip neighbor show
Kamar yadda zaku iya lura, adireshin MAC na na'ura mai ba da hanya tsakanin hanyoyin sadarwa yana da yawa. Idan akwai matsala ta ƙuduri, umarnin baya dawowa babu fitarwa.
Wannan shine shimfidar da zaku keɓance tare da adiresoshin IPv4 waɗanda suka saba da masu gudanar da tsarin. Yana bayar da ladabi da yawa kamar ICMP da ARP waɗanda muka rufe su da sauransu kamar RIP (Hanyar Ba da Bayani).
Wasu daga cikin matsalolin gama gari sun haɗa da sake fasalin na'urar ko matsaloli tare da na'urorin cibiyar sadarwa kamar magudanar hanya da sauyawa. Kyakkyawan wuri don fara gyara matsala shine bincika idan tsarin ku ya zaɓi adireshin IP kamar haka:
$ ifconfig
Hakanan, zaku iya amfani da umarnin ping don bincika haɗin intanet ta hanyar aika fakitin amsa kuwwa na ICMP zuwa DNS na Google. Tutar -c tana nuna yawan fakitin da ake aikawa.
$ ping 8.8.8.8 -c 4
Sakamakon ya nuna amsa mai kyau daga DNS na Google tare da asarar fakiti mara nauyi. Idan kuna da haɗin haɗin kai tsaye, zaku iya bincika wane batu ana sauke fakiti ta amfani da umarnin traceroute kamar haka.
$ traceroute google.com
Alamomin taurari suna nuna ma'anar da ake jefa fakitoci ko ɓacewa.
Umurnin nslookup yana bincika DNS don samun adireshin IP ɗin da ke hade da yanki ko sunan mai masauki. Wannan ana kiransa azaman Binciken DNS na gaba.
Misali.
$ nslookup google.com
Umurnin ya bayyana adiresoshin IP da ke hade da yankin google.com.
Server: 127.0.0.53 Address: 127.0.0.53#53 Non-authoritative answer: Name: google.com Address: 142.250.192.14 Name: google.com Address: 2404:6800:4009:828::200e
Umurnin tona wani umarni ne da ake amfani dashi don bincika sabobin DNS hade da sunan yanki. Misali, don tambaya ga masu saka sunayen DNS gudu:
$ dig google.com
Launin safarar yana ɗaukar watsa bayanai ta amfani da ladabi na TCP da UDP . Kawai don sake bayani, TCP yarjejeniya ce mai daidaituwa yayin da UDP ba shi da alaƙa. Gudanar da aikace-aikacen saurara a kan kwantena wanda ya ƙunshi tashar jiragen ruwa da adiresoshin IP.
Matsalolin gama gari waɗanda zasu iya faruwa gami da katange tashoshin TCP waɗanda ƙila aikace-aikace ke buƙata. Idan kana da sabar yanar gizo kuma kana son tabbatar da yadda take gudana, yi amfani da umarnin ss don bincika idan sabis ɗin yanar gizon yana sauraron tashar jiragen ruwa 80
$ sudo netstat -pnltu | grep 80 OR $ ss -pnltu | grep 80
Wasu lokuta ana iya amfani da tashar jiragen ruwa ta hanyar sabis mai gudana a cikin tsarin. Idan kuna son wani sabis don amfani da wannan tashar, ƙila a tilasta ku ku saita shi don amfani da tashar jirgin ruwa daban.
Idan har yanzu kuna fuskantar matsaloli, bincika Tacewar zaɓi kuma tabbatar idan an toshe tashar tashar da kuke sha'awar.
Yawancin matsala za su faru a cikin waɗannan matakan 4. Ana yin ɗan matsala kaɗan a cikin zaman, gabatarwa, da matakan aikace-aikace. Wannan saboda suna taka muhimmiyar rawa a cikin aikin hanyar sadarwa. Koyaya, bari mu hanzarta samun bayyani game da abin da ke faruwa a waɗancan layuka.
Layer zaman yana buɗe tashoshin sadarwa da ake kira zaman kuma yana tabbatar da cewa suna buɗe yayin watsa bayanai. Shima yana rufe sannan da zarar an daina sadarwa.
Hakanan an san shi da layin haɗawa, shimfidar gabatarwa yana haɗa bayanan da za a yi amfani da su ta hanyar aikace-aikacen. Yana bayyana yadda na'urori zasu ɓoye, ɓoye da kuma matse bayanai tare da manufar tabbatar da an karɓa sosai a ɗaya ƙarshen.
Aƙarshe, muna da Layer aikace-aikacen wanda shine mafi kusa ga masu amfani da ƙarshen kuma yana basu damar ma'amala da software na aikace-aikacen. Launin aikace-aikacen yana da wadataccen ladabi kamar HTTP, HTTPS, POP3, IMAP, DNS, RDP, SSH, SNMP, da NTP don ambaton kaɗan.
Lokacin magance matsala na tsarin Linux, hanyar da aka shimfida ta amfani da samfurin OSI ya zo da shawarar sosai, farawa daga layin ƙasa. Wannan yana ba ku damar fahimtar abin da ke faruwa ba daidai ba kuma yana taimaka muku don rage matsalar.