Shin ƙaramin MTU na VPN ya fi sauri? Kwatanta ainihin hujja
Ƙaramin MTU na iya guje wa iyakar hanya kuma har yanzu ya ci kuɗin wucewar bayanai. Kwatanta ainihin ƙuntatawa, kuɗin kanun kai da aikin kafin ka riƙe canjin.
Tunnel yana watsar da manyan ayyukan canja wuri amma yana barin ping ya wuce, don haka shawara tana zuwa da sauri: rage MTU. Gyaran yana aiki wani lokaci, sannan ana amfani da shi ga kowane bayanin martaba a kowace cibiyar sadarwa. A nan ne gyaran da aka yi niyya ya juya ya zama haraji na dindindin a kan aiki. Kwatancin da ya kamata a yi shi ne tsakanin ainihin iyakar hanyar da kuɗin rage kowane fakiti a ƙasa da ita.
Me ke raguwa da gaske sa’ad da ka rage MTU
Kowane fakiti yana ɗaukar kanun kai kafin ya ɗauki bayananka. A hanyar Ethernet mai baiti 1500, IPv4 da TCP suna cinye baiti 40 kuma suna barin 1460 don kaya; rufewa yana ƙara kanun kai na waje na IP, UDP da tunnel a sama, don haka kasafin kayan ciki ya sake faɗuwa. Rage MTU na mu’amala yana rage wannan kasafin da gangan.
Kuɗin yana daidai da adadin fakiti, ba adadin baiti ba. Fayil ɗaya da aka raba cikin fakiti da yawa yana buƙatar ƙarin katsewa, ƙarin shawarwarin hanya da ƙarin aiki kan kowane fakiti a kowace na’ura a kan hanyar. A kan na’urar jagora da ta riga ta kusa da iyakarta ta fakiti a cikin daƙiƙa, wannan jinkiri ne na gaske ba kuskuren zagaye ba. Kuɗin yana bayyana ko da canja wurin kansa ya yi nasara.
Shi ya sa ƙaramin MTU hanya ce ta kauce wa ƙuntatawa, ba ingantawa ta gama gari ba. Yana sayen aminci a gaban hanyar da ba za ta iya ɗaukar babban firam ba, kuma yana karɓar kuɗin kanun kai ga kowane fakiti da bai buƙaci raguwar ba.
Yaushe ƙaramin MTU shine gyara mai kyau
Alamar gargajiya ta tabbata: hannun TCP yana cika, ƙananan amsoshi suna isowa, kuma babban zazzagewa yana tsayawa ko an sake saita shi. Ping da bit ɗin kada-a-tsaga a baiti 1472 yana kasawa yayin da ping na baiti 1400 ya yi nasara, wanda ke nuna hanyar da ba za ta iya ɗaukar fakiti cikakken girma ba kuma ba ta isar da saƙon ICMP da zai gaya wa mai aikawa ya rage.
Gano MTU na hanya ya dogara da waɗannan saƙonni na ICMP na buƙatar tsagawa. Lokacin da bangon wuta ya jefa su, mai aikawa yana ci gaba da sake gwada babban faktin kuma haɗin yana kama da ya rataye. Rage MTU a gefen tunnel yana guje wa maimaitawa, kuma wannan gyara ne na halal ga wannan cibiyar sadarwa.
Fasahar shiga ma tana sanya iyakokinta: PPPoE yawanci yana tsayawa a 1492, wasu hanyoyin wayar hannu da DSL sun fi ƙasa, kuma tunnel ɗin da aka yi gida biyu suna cire kuɗin kanun kai sau biyu. Auna ainihin hanyar maimakon kwafin lamba daga jagora, kuma ka tuna cewa IPv6 yana buƙatar aƙalla baiti 1280 na MTU a kowace hanyar da take ɗaukarsa, kamar yadda RFC 8200 ya bayyana.
Kwatanta abubuwan sarrafawa uku kafin ka canza ɗaya
MTU, MSS da tsagawa abubuwan sarrafawa ne daban-daban a matakai daban-daban, kuma canza wanda bai dace ba yana barin alamar a wurinta.
| Control | Layer | What it changes | Where it misleads |
|---|---|---|---|
| Interface MTU | IP link | Largest frame the interface will send | Penalizes every protocol, not just the one that failed |
| TCP MSS clamp | TCP | Segment size advertised in the handshake | Leaves UDP and QUIC untouched |
| DF and fragmentation | IP | Whether a router may split a packet | Can break path MTU discovery and security assumptions |
| Tunnel overhead | Encapsulation | Inner MTU after outer headers | Mismatch shows up only for large inner packets |
Iyakance MSS sau da yawa shine gyara mafi ƙarancin shiga saboda yana shafar TCP kawai kuma yana barin mu’amala a ’yanci ga sauran zirga-zirga. Ƙaramin MTU na mu’amala ya fi faɗi kuma ya fi sauƙin yin tunani akai, shi ya sa ya zama ruwan dare a kan na’urorin jagora na masu amfani, amma yana karɓar kuɗin matsalar wata yarjejeniya daga kowace yarjejeniya.
Kashe halin kada-a-tsaga yana ɓoye alamar ta hanyar barin tsagawa, kuma yawanci yana ƙara muni ga jinkiri yayin da yake karya martanin da zai sami daidai girman. Ka guje wa hakan a matsayin magani na dindindin.
Auna musanya maimakon lamba ɗaya
Nemo iyakar hanyar da bincike na kada-a-tsaga, fara daga sama ka sauko har sai amsa ta iso:
ping -M do -s 1472 203.0.113.10
ping -M do -s 1400 203.0.113.10
tracepath 203.0.113.10Sannan kwatanta ainihin aikin a kan saitunan biyu: canja wurin fayil ɗaya, ƙarshen ɗaya da cibiyar sadarwa ɗaya. Rubuta lokacin kammalawa da sake aikawa, alal misali da nstat -az TcpRetransSegs, kuma lura da CPU na na’urar idan tunnel ya ƙare a kan ƙaramin na’urar jagora. Gwajin wucewar bayanai na ɗan lokaci na wucin gadi zai iya rasa tsayawar da ke bayyana sai bayan megabait da yawa.
Ma’aunin fakiti zai tashi bayan raguwa saboda canja wurin ɗaya yanzu yana amfani da fakiti da yawa. Wannan ana tsammani kuma ba hujja ba ce ta wucewa mafi girma. Kwatanta bayanan aikace-aikacen da aka kammala, adadin sake aikawa da amsawa, ba kawai yawan fakiti ba.
Ka shigar da canjin mataki-mataki kuma ka riƙe shi cikin iyaka
Rubuta ainihin darajar, canza abin sarrafawa ɗaya, kuma sake maimaita auna kafin ka mai da shi na dindindin. Idan hujjar ba ta nuna wata fa’ida ba, maido da darajar da ta gabata da wannan umarnin mu’amala da ka yi amfani da shi wajen saita ta:
ip link set dev wg0 mtu 1420
ip link set dev wg0 mtu 1500Iyakance sakamakon ga cibiyar sadarwar da ta buƙace shi. Bayanin martabar da dole ya yi aiki a Wi-Fi na otal, hotspot na wayar hannu da LAN na ofis bai kamata ya gaji mafi ƙarancin darajar da kowannensu ke buƙata ba, sai dai idan abokin ciniki ba zai iya gano hanyar ba.
Daidai darajar ita ce mafi girman MTU da ke tsira a hanyar, ba mafi ƙanƙanta da ke sa alamar ta ɓace ba. Rubuta hanyar, sakamakon binciken da juyawa baya, kuma sake duba saitin lokacin da cibiyar sadarwar shiga ta canza.