I-BGP ifunde i-prefix, kodwa ithrafikhi isagwema umgudu

Isango legatsha likhombisa i-prefix yefu kuthebula laso le-BGP, umhlangano nomhlinzeki usungulwe, kodwa isicelo somsebenzisi kuleyo prefix sisaphuma ngomhubhe ongafanele. Akukho okonakele ngendlela eya esiboniselwa ukuqapha, ngoba “i-BGP iyifundile” isitatimende esimayelana nebanga lokulawula. Phakathi kwalelo thebula nephakethe kunezinguquko ezine ezihlukene, futhi ukugeleza kuma kwelinye lazo ngqo. Hamba ngamasango ngokulandelana futhi ume kwelokuqala elihlulekayo.

Isango lokuqala: umakhelwane wathumela ini ngempela

Qala nge-prefix njengoba yamukelwa, hhayi njengoba ifingqiwe. Thola inethiwekhi nemaski eqondile kuthebula le-BGP bese ubhala ukugxuma okulandelayo, umzila we-AS nanoma imuphi umphakathi umgomo wokungenisa ongahambisana nawo. Umzila ofingqiwe kudeshibhodi ungafihla iqiniso lokuthi leyo prefix ethile ayikaze yamukelwe.

Umgomo wokungenisa yindawo ejwayelekile lapho umzila unyamalala ngaphandle kwephutha. Uhlu lwama-prefix, isihlungi somphakathi noma imephu yomzila ongenayo kungalahla isibuyekezo ngenkathi umhlangano uhlala phezulu futhi uphilile, yingakho ukukhanya komakhelwane okuluhlaza kufakazela okuncane kangaka. Ukungabikho komugqa welogi akusho ukungabikho kwesinqumo. Ngokuvamile kusho ukuthi isinqumo sathathwa buthule, ngqo njengoba kulungisiwe.

show ip bgp 10.60.20.0/24
show ip bgp neighbors 203.0.113.5 advertised-routes
show ip route 10.60.20.0
show ip cef 10.60.20.0

Funda umphumela ngalolo hambo. Imiyalo emibili yokuqala ithi ulwazi lufikile yini nokuthi i-peer ithi yathumela ini; emibili yokugcina ithi kukhona okufike emithebuleni yokuhlela nokudlulisa yini. I-prefix ekhona kumyalo wokuqala futhi engekho kowesithathu iyinkinga yokukhetha noma yokufaka, hhayi inkinga yokuxhumana.

Isango lesibili: ukukhetha, bese kuba ukufaka

I-BGP ikhetha umzila ongcono kakhulu, futhi umzila okhethiwe awufakwa ngokuzenzakalela. Ukugxuma okulandelayo kufanele kuxazululwe, futhi omunye umthombo wemizila kungenzeka usunayo leyo prefix ngebanga elingcono lokuphatha. Umzila oqinile osele kusukela ekufudukeni uzokwehlula kalula umzila we-BGP ovumelekile bese uthumela ithrafikhi kwenye indawo.

RFC 4271 igcina imibono emithathu ihlukene: i-peer yathumela ini, lesi sikhulumi sakhetha ini njengokungcono kakhulu, nokuthi sizomemezela ini phambili. Lawa ngamadima omqondo, hhayi izisekelo zedatha ezintathu ezibonakalayo okufanele umthengisi azidalule, kodwa ukwehlukana kukho kwenziwa “ikuku-BGP” kube impendulo engaphelele.

Futhi hlola ukuthi yikuphi umongo wokuhlela owufundayo. Umzila ofakwe ku-VRF okungeyona yayo i-interface yomsebenzisi awubonakali kumaphakethe walowo msebenzisi, futhi ithebula libonakala lilungile ngaso sonke isikhathi.

Isango lesithathu: ukusesha okusebenza kulokhu kugeleza

Manje yeka ukubuza ngomzila bese uqala ukubuza ngephakethe. Bhala ikheli lomthombo lomsebenzisi, indawo okuya kuyo, iphrotokol, imbobo kanye ne-interface engenayo, ngoba ngakunye kwazo kungakhetha umgomo ohlukile. Bese ubheka ukusesha okusebenza kuleyo nhlanganisela esikhundleni sethebula jikelele lokuhlela.

ip route get 10.60.20.25 from 10.60.10.40
ip rule show
sudo tcpdump -ni tun0 'host 10.60.20.25'

I-prefix ethile kakhulu iyisimangaliso esivame kakhulu lapha, futhi umzila womgomo ungowesibili. Kokubili kudlula i-aggregate obukuyo, futhi akukho ngakunye okubonakala kusifinyezo sethebula le-BGP.

I-ping ethunyelwe kusukela esangweni uqobo akuwona ubufakazi mayelana nomhlangano womsebenzisi. Ikheli lomthombo elihlukile, umzila womgomo ohlukile, futhi ngokuvamile umphumela ohlukile. Hlola ngomthombo ofanayo osethenziswa uhlelo, noma vuma ukuthi ukuhlolwa kuphendula omunye umbuzo.

Isango lesine: ingxenye ekude yomzila

Uma ukusesha kwasendaweni kukhetha umgudu ngempela, iphakethe kusafanele lamukelwe umgomo wokuvikela, livunyelwe umthetho wokudlulisa, futhi liphendulwe okuthile ohlangothini olude. I-ACL yokubethela engabandakanyi ipheya lamakheli izolahla ithrafikhi ngenkathi umgudu uzibika uphezulu, okukhiqiza isikhathi sokuphela esingahlukaniseki nokwehluleka kokuhlela.

Umzila wokubuya ubaluleke ngokulingana nowokuya. Uhlangothi lwefu kufanele lwazi ukuthi lufinyelela kanjani emthonjeni wegatsha, kungaba ngomzila noma ngokuhumusha okulungise ngamabomu. Imizila yokubuya engalingani ivamile emiklamweni ehlolwe ohlangothini olulodwa kuphela.

Xhumanisa uxhumano olusanda kugunyazwa nokubhekwa okuthathu: umgomo wasendaweni owafanayo, izibali zomgudu ezinyakazile, nokwamukelwa ohlangothini olude lapho kubonakala khona. Uma izibali zinganyakazi, iphakethe alizange lingene emgudwini, kusho ukuthini ithebula lemizila. Uma zinyakaza futhi kungafiki lutho, uhlangothi olude luyalahla noma luhlela kabi. Le miphumela emibili iholela emaqenjini ahluke ngokuphelele.

Qamba inguquko ehlulekile

Bhala umphumela njengesinye sezimo ezinhlanu: akwamukelwanga, akwamukelwanga umgomo, akukhethwanga, akufakwanga, noma akuhambisananga nalokhu kugeleza. Faka eyesithupha esimweni lapho umzila wasendaweni ulungile futhi umgxeke wokugcina awukwazi ukuphendula. Lowo mugqa uyilokho okumele kudluliswe, futhi uwusizo kakhulu kunomfanekiso wesikrini womakhelwane osunguliwe.

Futhi gcina ukuhlolwa okungalungile kuhlelo lokwamukela: indawo okungafanele idlule emgudwini, eqinisekisiwe ngemva koshintsho. Uhlu lokuhlola olufakazela umzila omuhle kuphela ngeke lubambe umthetho womgomo obanzi othile angawufaka kuwindi lokulungisa elilandelayo.