I-SSH iyakhawuleza ukuma ku-OpenVPN? Kala i-MTU yendlela kuqala

I-SSH iyaxhuma, umkhombandlela uyavela, futhi iseshini iyafa ngokushesha lapho umyalo ubuyisa into enkulu. I-echo isasebenza isikhashana, bese uxhumano luphelelwa yisikhathi kuyilapho iklayenti lisabonisa umhubhe njengophezulu. Iseshini ephilile kuze kufike idatha ivamise ukushayisa umkhawulo wosayizi hhayi ukungabi kahle kwe-SSH. Izivivinyo ezingezansi zihlelwe ukuze incazelo eshibhile isuswe kuqala.

Funda isimo sokwehluleka ngaphambi kokuthinta iphrofayela

Amaphakethe amancane ayadlula kanti agcwele awadluli. Umkhombandlela, ibhana noma ukucindezela ukhiye kube kukodwa kungena kalula; uhlu lwefolda, ukulanda noma ibhulokhi elinanyisiwe akungeni. Usayizi okushintsha kuwo ukuziphatha yiwona mkhondo, hhayi ukuthi i-SSH iwuhlelo oluhilelekile.

Indlela yile: ukutholwa kwe-MTU yendlela, okuncike ekuphenduleni. I-TCP ikhetha usayizi wesigaba, futhi lapho umzila endleleni ungakwazi ukudlulisa iphakethe elivela khona kufanele akwazise ngesithunywa se-ICMP. Ukuhlanganisa kwenza iphakethe langaphandle libe likhulu kunelangaphakathi, ngakho usayizi osebenzisekayo ngaphakathi komhubhe uhlala ngaphansi kwesixhumanisi somzimba. Hlunga lezo zithunywa ze-ICMP noma kuphi futhi umthumeli akasoze athole ukulungiswa, uzoqhubeka nokuthumela izigaba ezigcwele, futhi iphakethe langaphandle lilahliwe ngaphandle sesaziso.

Kala umkhawulo kuzinhlangothi zombili

Qhathanisa i-MTU yomhubhe nesixhumanisi somzimba ngaphambi kokushintsha okukodwa kwazo. Umhubhe okhuphelele lo msebenzi wezomzimba ushilo ukuthi ukungafani kukuphi.

Vivinya ngaphakathi komhubhe ngesicelo esivimbela ukuhlukaniswa, wehlisa umthwalo kuze kubuya izimpendulo. Ingxabano yosayizi ibala umthwalo kuphela, ngakho inombolo esebenzayo ihlala ingaphansi kwe-MTU yesikhombisi. Faka futhi usayizi wezihloko uma udinga inombolo yesikhombisi.

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Phinda isivivinyo kukheli lomphakathi leseva ngaphandle komhubhe. Uma izivivinyo ezinkulu zehluleka lapho futhi, umkhawulo usendleleni eya kuseva futhi akukho ukukhetha komhubhe okuzowususa. Lokho kuqhathanisa kukusindisa ekulungiseni iklayenti elalingeyona inkinga. Bhala imiphumela yomibili ngaphambi kokuvula ifayela lokumisa.

i-mssfix ne-fragment benza imisebenzi ehlukene

mssfix inconyusa usayizi wesigaba okumemezelwa yiwo ukuxhumana kwe-TCP ngaphakathi komhubhe ngesikhathi sokuxhawulana kwabo. Yilokhu okulungile kwe-SSH, i-HTTPS nokukopisha amafayela, yingakho ukuma kuvame ukunyamalala ngokushesha lapho kusethiwe. Akuthinti imithwalo ye-UDP nhlobo.

Umhubhe othwala nesinsizakalo se-UDP ungase uqhubeke ukwehluleka ngemva kokulungiswa kwe-SSH, futhi lomphumela udida noma ngubani ocabanga ukuthi ukukhetha okukodwa kuhlanganisa konke.

fragment ingenye indlela nethuluzi elihlukile. Ihlukanisa amaphakethe amakhulu kakhulu ngaphambi kokuhlanganisa, isebenza kuphela ekuthuthukisweni kwe-UDP, yengeza izindleko ngedatha yedathagramu ngayinye futhi ibhalwe njengendlela yokugcina yokutholwa okuphukile. Zombili izilungiselelo kufanele zifane kozakwethu abaqeda umhubhe. Lapho uhlangothi olulodwa lucindezela kanti olunye luhlukanisa, kuvela izexwayiso zelogi nokuziphatha okungekho muntu ongakubikezela kusukela kumafayela.

Ukwehlisa i-MTU yesikhombisi yikho okukhethiwe okugwemayo

Ukwehlisa i-MTU yesikhombisi kuzinhlangothi zombili yithuluzi eligwemayo. Litshela wonke umthumeli wangaphakathi inombolo encane, okusebenzayo, futhi lifaka lezo zindleko kulo lonke ukuxhumana esikhundleni semigudu ye-TCP eyidingayo.

Ikhetha lapho umhubhe uthwala ukuxhumana ongeke ukwazi ukukunciphisa, noma lapho iklayenti liwuhlelo ongeke ulawule iphrofayela yalo. Kufake ngokulingana bese ubhala inani eduze kwephrofayela. Ushintsho olusetshenziswe uhhafu lubi kunokungabi nalutho, ngoba lubukeka njengokulungiswa.

Phinda uvivinye ngokudluliswa okwama

Xhuma futhi ukuze izilungiselelo zilayishe, vula uxhumano olusha futhi uphinde umyalo owagodola. Usayizi wesigaba uxoxwa ngesikhathi sokuxhawulana, ngakho iseshini eyasinda ekuxhumweni kabusha isathwala inani elidala. I-ping isivivinyo esibuthakathaka lapha, ngoba ukwehluleka konke ukuthi amaphakethe amancane ayadlula. Sebenzisa uhlu, ukulanda noma ukunanyisa okwaphuka.

Uma ukuma kuqhubeka ngosayizi omncane, bheka kwenye indawo: umlilo onomumo ogcina ugcina umgudu uphele, ikheli eliphindwe kabili, noma umzila oshintshayo ekuxhumweni kabusha. Bhala usayizi wesivivinyo esihlulekile kanye nesilungiselelo osishintshile, ngoba yilelo bhangqa elenza umbiko olandelayo ube usizo.