I-/24 efanayo kumakhasimende amabili? I-VPNv4 idinga i-RD nelebula
Abaqashi ababili bangamemezela i-/24 efanayo kuphela ngoba i-RD inika umzila ngamunye ubunikazi bawo. Ilebulu liphendula umbuzo ohlukile: kudluliswa kanjani.
Abaqashi ababili babhala igatsha labo ngenombolo efanayo 10.50.0.0/24, futhi ngemva koshintsho umzila womunye unyamalala emaphethelweni omshini wokuhlinzeka kuyilapho omunye uqhubeka usebenza. Ukwenza lula okungemva kwalelo thikithi ngokuvamile ukushiya umhlukanisi womzila (RD) ngoba „ilebula selivele likhomba ikhasimende“. Akwenzi kanjalo. I-RD nelebula ziphendula imibuzo emibili ehlukene, futhi igebe libonakala kuphela lapho amakheli anqwabelanayo ephoqa lokho.
Umzila owodwa lapho bekufanele kube khona emibili
I-IPv4 unicast evamile iqhathanisa imizila emibili eya kuqoqo elifanayo lokuqala futhi ifake engcono. 10.50.0.0/24 evela kuqashi A kanye ne-10.50.0.0/24 evela kuqashi B kuwukhiye owodwa, ngakho eyodwa iyanqoba futhi enye isinda kuphela njengomzila wesipele. Iphrothokholi yenza okwatshelwa yona; indawo yokulawula yacelwa ukuba igcine imizila emibili ehlukene ngaphansi kwesihlonzi esisodwa.
Umphumela ubonakala njengomzila olahlekile hhayi njengephutha: i-PE elahlekelwe umncintiswano isadlulisa umqashi wayo ngokwasendaweni, ngakho ukuhlolwa ngaphakathi kwesayithi kuyaphumelela kanti ukuhlolwa phakathi kwamasayithi kuyahluleka. Ngaphambi kokuthinta noma iyiphi inqubomgomo, bala okufakiwe kwalelo qoqo lokuqala kuthebula le-VPNv4.
I-RD iguqula ukhiye owodwa ube ngamabili
Umhlukanisi womzila wamabhayithi ayisishiyagalombili ufakwa phambi koqoqo lokuqala lwe-IPv4, futhi into ethwalwa yi-BGP iba ikheli le-VPN-IPv4 esikhundleni soqoqo lokuqala lwe-IPv4. Abaqashi ababili bangagcina ama-bithi angama-32 afanayo ngoba ama-bithi angama-64 angaphambili ahlukile. Kukhona izinhlobo zefomethi ze-RD esekwe ku-AS neyesekwe ekhelini, futhi ukukhetha kungokwe-PE yomsuka. I-RD esekwe ku-AS ivamile lapho ama-PE abelana nge-AS eyodwa, kanti eyesekwe ekhelini lapho engabelani.
Ungayifundi i-RD njengethegi yobulungu. Izinhloso zomzila zilawula ukungenisa nokukhipha futhi zinquma ukuthi yimaphi ama-VRF angafaka umzila; i-RD iqinisekisa kuphela ukuthi umzila unobunikazi bawo. Ukunika i-VRF ngayinye i-RD yayo uqobo kuwumkhuba ojwayelekile ngoba kugcina lokho kuhlelo kufundeka kusibuki somzila.
Ilebula liwumyalo wokudlulisa wasendaweni
Isimemezelo ngasinye sithwala nelebula ye-MPLS, futhi incazelo yayo ilinganiselwe kumzila oyihlele. Enye i-PE ingakhipha inombolo efanayo endaweni engahlobene. Yingakho ilebula lingenakuthatha isikhundla sobunikazi bekhasimende: inombolo ilungile kuphela eduze kwegxatho elilandelayo nesimo sokudlulisa esiyifakile.
Ubukhulu bokwabiwa buyahluka ngokuya ngokusebenza nokwakhiwa: amanye amapulatifomu abela ilebula elilodwa nge-VRF ngayinye, amanye ngoqoqo lokuqala ngalunye, futhi ilebula lingakhomba isenzo sokudlulisa hhayi ikhasimende. Amalebula amabili ahlukene afinyelela endaweni eyodwa akuzona ukuphikisana, futhi nenombolo yelebula efanayo kuma-PE amabili akuzona.
| Field | Where it lives | Scope | If you remove it |
|---|---|---|---|
| RD | VPNv4 NLRI | Per advertised route | Overlapping prefixes collide |
| Route target | Extended community | Import and export policy | Route lands in the wrong VRF |
| Label | Labeled NLRI and forwarding state | Per allocating router | No instruction for the data plane |
| Next hop | Path attribute | Per path | The label cannot be resolved |
Kungani elinye lingenakuthatha isikhundla somunye
Ukufunda isimemezelo kusho ukubheka izinto ezine ndawonye: uqoqo lokuqala olugunyazwe yi-RD, izinhloso zomzila, igxatho elilandelayo nelebula. Ukufunda iphakethe lomsebenzisi kusho ukubheka isitaki esifakwe kusukela kulolo lwazi. Ukwakhiwa okunempilo kubonisa izinhlangothi zombili zivumelana, futhi okugqekile ngokuvamile kunohlangothi olulodwa olulungile nolunye olugugile. Lokho kuqhathanisa kuhlukanisa inkinga yobunikazi enkingeni yokudlulisa.
Umehluko ocwebile phakathi kwendawo yokulawula nendawo yedatha uyithuluzi lokufundisa, hhayi incazelo yokubhala ikhodi. RFC 8277 ibeka ilebula ngaphakathi kwe-NLRI enelebula, ngakho isimemezelo ngokwaso sithwala ukuxhumana; ukulisebenzisa ekudluliseni kuyisinyathelo sakamuva, esihlukile.
Lapho umzila womqashi ungekho, hlola ngokulandelana lokhu: okufakiwe okubili kwe-VPNv4 koqoqo lokuqala, inhloso yomzila efanele kokunye ngakunye, igxatho elilandelayo elingaxazululeka, nelebula i-PE eyamukelayo enesimo sayo. Ukulungisa ubunikazi ngenani lokudlulisa, noma okuphambene nalokho, kuzodlula ukuhlolwa okukodwa futhi kuhluleke kolulandelayo.