Ingabe i-TCP 443 iyasiza ngempela? Kuphela uma iseva ilalela lapho
Iphrofayela ye-TCP iyindlela yokubuyela emuva, hhayi ukuzifihla. Qinisekisa ukuthi iseva ilalela kuleyo port, bese ukala izindleko ze-TCP eziphindwe kabili ngokumelene nokungafinyeleleki.
I-TCP 443 iyindlela yokubuyela emuva enesimo esandulelayo, hhayi ukuzifihla okudlulisa ithuneli ngale kwanoma yisihlungi. Iyasiza uma umhlinzeki esekhipha isilaleli se-TCP kuleyo port futhi indlela ibekezelela ukuxhumana okuhlala kuvuliwe amahora amaningi. Iyehluleka, ngokuvamile njengesikhathi sokuphelelwa, uma kokubili koku kungabikho, futhi isikhathi sokuphelelwa akuvamisile ukusho ukuthi yikuphi. Isinqumo sokushintsha sidinga imibuzo emithathu, futhi munye kuphela wabo omayelana nenombolo ye-port.
Inombolo ye-port ayisona isethembiso sokuhamba
I-port iqamba iphoyinti lokugcina; i-TCP iyiguqula ibe umfudlana wamabhayithi ohlelekile; OpenVPN inquma ukuthi yini ihamba ngaphakathi kwalowo mfudlana. Iseva yewebhu kuleyo nombolo isebenzisa ukuhlelwa kohlelo oluhluke ngokuphelele, ngakho ukwabelana nge-port 443 kwenza kokubili kubonakale kufana kusihlungi futhi akukho okunye. Inombolo iyikhombisi elifundwa isihlungi, hhayi isici esishintsha okuqukethwe amaphakethe. Ukuzithatha zombili njengento eyodwa ngenxa yokuthi zabelana nge-port iyiphutha elingemuva kokudideka okuningi lapha.
Amadivayisi aphakathi awavamile ukuthatha isinqumo esilula sokuvumela-noma-ukuvimbela nge-port. Amaningi ahlola amabhayithi okuqala, amanye abopha indawo okuyiwa kuyo, kanti amanye asetha kabusha ukuxhumana okuhlala kuvuliwe isikhathi eside. Yikho lokhu okwenza iphrofayela efanayo isebenze kusuka kunethiweki eyodwa futhi iphelelwe yisikhathi kwenye, futhi yikho okwenza kufanele ukuthi indlela yokubuyela emuva ihlolwe njengenketho esekelwayo esikhundleni sokuyethemba njengesethembiso. Uma isihlungi sihlola ithrafikhi, inombolo ye-port iyinto yokuqala esiyibonayo kuphela.
Qinisekisa isilaleli ngaphambi kokuthinta iphrofayela
Iseva kufanele ihlelwe nge-TCP kuleyo port, futhi iphrofayela yeklayenti kufanele icele ukuhamba okufanayo. Ukubhala kabusha iphrofayela ye-UDP ukuze icele i-TCP akukudali isilaleli, futhi isikhathi sokuphelelwa esivela kulokho asihlukaniseki nomdwa womlilo ophonsa i-port. Landa iphrofayela ye-TCP yomhlinzeki uqobo uma ikhona, ngoba ezinye izinsizakalo zishicilela iphoyinti lokugcina elihlukile nezilungiselelo zobunikazi ezihlukile kokuhamba ngakunye. Ukuhlela ngesandla kulungele ukuhlolwa okulawulwayo futhi kuyindlela embi yokuqagela ukuhlelwa okuhloswe umhlinzeki.
Izinhlangothi zombili zalokho kufana zivela ekuhlelweni, futhi izinketho zokuxhuma zephrojekthi ye-OpenVPN zibhala zombili izinhlobo. Ipheya elincane libukeka kanje:
# server: accept TCP on this port
proto tcp-server
port 443
# client: request the same transport
proto tcp
remote vpn.example.com 443Izimo ezintathu zinuma ukuthi indlela yokubuyela emuva iyakhokha yini
Isimo sokuqala siwukuthi umhlinzeki unikeza lokho kuhamba nhlobo; ngaphandle kwakho akukho okunye okubalulekile. Eyesibili siwukuthi indlela igcina isikhathi eside seseshini siphila, ngoba ezinye izixhumi zisetha kabusha ukuxhumana okuhlala kuvuliwe esikhundleni sokuvala i-port ngokuphelele. Eyesithathu siwukuthi indlela yokubuyela emuva iwukuhluka okwenziwe ngamabomu noma isixazululo sesikhashana esifihla iphutha ongalungisanga.
Isimo ngasinye sinokuhlola okushibhile. Ukwehluleka kwesinye sazo kubonakala kufana ngasohlangothini lweklayenti:
| Condition | How to check it | What a failure decides |
|---|---|---|
| The server offers TCP | The operator's profile list, or a listening-socket check on the server | No client-side edit can help |
| The path keeps long sessions | A test connection left open for an hour | Reconnects will look like server faults |
| The fallback is deliberate | A change record naming the UDP fault | The underlying fault stays invisible |
Ngaphambi kokuqhathanisa ukuhamba, qeda noma yikuphi ukungena ku-portal ebambayo. Inethiweki engakamukeli idivayisi yakho ivimbela zombili izinhlobo zokuhamba, futhi lapho ukuqhathanisa kukala i-portal hhayi ithuneli. Ngena, qinisekisa ukuthi ukuphequlula okuvamile kuyasebenza, bese uqala ukuhlolwa ngemva kwalokho.
Izindleko ozamukelayo: i-TCP ngaphakathi kwe-TCP
I-TCP ithumela kabusha amasegmenti alahlekile futhi igcina ukulandelana kwawo. Uma uhlelo olusebenzisa ne-TCP lugijima ngaphakathi kwethuneli le-TCP, izingqimba ezimbili zokubuyisela zisabela ekulahlekelweni okufanayo, futhi ukusebenzisana kwalokho yikho okwenza ithuneli libonakale lihamba kancane endleleni enokulahleka. Uphawu ukubambezeleka nokudlikiza hhayi ukwehluleka okumsulwa, okwenza kube lula ukusola uhlangothi olukude. Kala kusuka kuklayenti kuzo zombili izinhlobo zokuhamba ngaphambi kokuphetha.
I-UDP igwema lokho kuhlanganisa, futhi yisizathu esiyinhloko sokuthi abahlinzeki bayithande futhi banikeze i-TCP njengenye indlela kuphela. Ukuxhumana kwe-TCP okuzinzile kusewusizo kakhulu kunokuxhumana kwe-UDP okungafinyeleleki, ngakho ukuqhathanisa kuphakathi kwezindleko ezimbili zangempela hhayi phakathi kwenketho enhle nembi. Gcina idivayisi nenethiweki yokufinyelela kungashintshile ngenkathi uqhathanisa, ngaphandle kwalokho umphumela uzochaza okuguquguqukayo okungalungile.
Ezinye izici zeklayenti zibhalwe kokuhamba okukodwa kuphela, ngakho iphrofayela yokubuyela emuva ingalahla buthule ukuziphatha obuthembele kukho. Funda imfuneko yokuhamba yalokho kukhetho ngaphambi kokuthatha iphrofayela ye-TCP njengokushintshana okulula.
Amaphutha okungawathinti okunye ukuhamba
Isitifiketi esiphelelwe yisikhathi sisadinga ukuhlolwa kwewashi noma ukuvuselelwa, futhi i-akhawunti enqatshiwe isadinga imininingwane efanele yokungena. Gcina ukuhlolwa kobunikazi beseva okunikezwe umhlinzeki, ngoba inombolo ye-port eyaziwayo ayiqinisekisi muntu. I-port ephendulayo isho kuphela ukuthi kukhona okulalelayo.
Uma ithuneli likhuphuka futhi izindawo okuyiwa kuzo zisahluleka, inkinga esele iwukuhamba kwendlela noma ukuxazululwa kwamagama ngemva kokuxhumana, hhayi ukuhamba. Landela leyo ndlela esikhundleni sokuzulazula kuma-port, ngoba yikho okushabalala ntambama eyodwa. Iphrofayela ikutshela ukuthi yikuphi ukuhamba okufanele ukuzame; ayikutsheli neze ukuthi kungani indlela ye-UDP yehlulekile.