Uninzi lwabantu lugcina umkhondo wexesha. Sivuka kwangethuba ukuze sigqibezele amasiko ethu akusasa kwaye siye emsebenzini, sithathe ikhefu lesidlo sasemini, sihlangabezane nemihla yokugqibela yeprojekthi, sibhiyozele imihla yokuzalwa neeholide, sikhwele inqwelomoya, njalo njalo.
Ngaphezu koko: abanye bethu baxakeke lixesha. Iwotshi yam inikwe amandla ngamandla elanga kwaye ifumana ixesha elichanekileyo kwiZiko lemiGangatho yeSizwe kunye neTekhnoloji () ukuya eFort Collins, eColorado ngerediyo yelongwave . Iimpawu zexesha zilungelelaniswa kunye newotshi yeathom, ekwafumaneka eFort Collins. IFitbit yam ingqamanisa nefowuni yam engqamanisa neseva , ethi ekugqibeleni idibane newotshi yeathom.
Izixhobo zigcina umkhondo wexesha nazo
Kukho izizathu ezininzi zokuba kutheni izixhobo zethu kunye neekhompyuter zifuna ixesha elichanekileyo. Ngokomzekelo, kwiibhanki, kwiimarike zemasheya, kunye namanye amashishini emali, ukuthengiselana kufuneka kuqhutywe ngendlela efanelekileyo, kwaye ukulandelelana kwexesha elichanekileyo kubalulekile kule nto.
Iifowuni zethu, iitafile, iimoto, iinkqubo zeGPS kunye neekhompyutha zonke zifuna ixesha elichanekileyo kunye noseto lomhla. Ndifuna iwotshi ekwidesktop yekhompyuter yam ibonise ixesha elichanekileyo. Ndifuna izikhumbuzo zivele kwikhalenda yam yasekuhlaleni ngexesha elifanelekileyo. Ixesha elichanekileyo likwaqinisekisa ukuba imisebenzi yecron kunye ne-systemd isebenza ngexesha elifanelekileyo.
Umhla kunye nexesha nazo zibalulekile ekugawulweni kwemithi, ngoko kulula kancinane ukufumana iilogi ezithile ngokusekelwe kumhla kunye nexesha. Ngokomzekelo, ndakhe ndasebenza kwi-DevOps (yayingabizwanga ngelo xesha) kwaye ndandiseta inkqubo ye-imeyile kwilizwe laseNorth Carolina. Besiqhele ukwenza ii-imeyile ezingaphezulu kwezigidi ezingama-20 ngosuku. Ukulandelela i-imeyile ngothotho lweeseva, okanye ukumisela ulandelelwano oluchanekileyo lweziganeko kusetyenziswa iifayile zelog kwinginginya ezisasazeke ngokwejografi, kunokuba lula kakhulu ukuba iikhompyuter ezichaphazelekayo zilungelelaniswa ngexesha.
Ixesha elinye - iiyure ezininzi
Inginginya zeLinux kufuneka zithathele ingqalelo ukuba kukho ixesha lenkqubo kunye nexesha le-RTC. I-RTC (Ikloko yeXesha lokwenyani) ligama elingaqhelekanga kwaye alichanekanga kakhulu kwiwotshi yehardware.
Iwotshi yehardware isebenza ngokuqhubekayo naxa ikhomputha icinyiwe, isebenzisa ibhetri kwimotherboard yesixokelelwano. Umsebenzi ophambili we-RTC kukugcina ixesha xa uxhulumaniso kwiseva yexesha lungekho. Ngeentsuku apho kwakungenakwenzeka ukudibanisa kwi-server yexesha kwi-Intanethi, yonke ikhompyutha kufuneka ibe newotshi yangaphakathi echanekileyo. Iisistim ezisebenzayo kwafuneka zifikelele kwi-RTC ngexesha lokuqalisa kwaye umsebenzisi kwafuneka aseke ngesandla ixesha lenkqubo esebenzisa ujongano loqwalaselo lwehardware yeBIOS ukuze aqinisekise ukuba ichanekile.
Iiwotshi zehardware aziyiqondi ingqikelelo yeendawo zexesha; I-RTC igcina ixesha kuphela, hayi izowuni yexesha okanye ukulinganisa ukusuka kwi-UTC (iXesha eliDityanisiweyo kwiHlabathi liphela, ekwaziwa ngokuba yi-GMT okanye iGreenwich Mean Time). Ungafaka i-RTC usebenzisa isixhobo endiya kusigubungela kamva kweli nqaku.
Ixesha lenkqubo lixesha apho i-OS ibonakalisa kwiwotshi ye-GUI kwidesktop yakho, kwimveliso yomyalelo womhla, kwizitampu zexesha zelog. Oku kusebenza kwakhona xa iifayile zenziwe, zilungiswa, kwaye zivulwa.
Kwiphepha kukho inkcazo epheleleyo ye-RTC kunye newotshi yenkqubo.
Yintoni nge-NTP?
Iikhompyutha kwihlabathi jikelele zisebenzisa i-NTP (iProtokholi yeXesha leNethiwekhi) ukungqamanisa ixesha lazo kunye neewotshi zereferensi eziqhelekileyo kwi-Intanethi zisebenzisa uluhlu lweeseva ze-NTP. Iiseva zexesha eliphambili zikumaleko woku-1 kwaye ziqhagamshelwe ngokuthe ngqo kwiinkonzo zexesha ezahlukeneyo zelizwe kumaleko 0 ngesathelayithi, unomathotholo okanye iimodem kwiintambo zomnxeba. Iinkonzo zexesha ze-Layer 0 inokuba yiwotshi yeathom, isamkeli sikanomathotholo esilungelelaniswe kwiimpawu ezihanjiswa ziiwotshi zeathom, okanye isamkeli seGPS esisebenzisa imiqondiso yewotshi echaneke kakhulu ethunyelwa ngeesathelayithi zeGPS.
Uninzi lweeseva zereferensi zinamawaka aliqela eeseva zikawonke-wonke ze-NTP ze-2 ezivuleleke kuluntu. Imibutho emininzi kunye nabasebenzisi (ndibandakanyiwe nam) kunye neenginginya ezininzi ezifuna iseva ye-NTP zikhetha ukuseta abancedisi bexesha labo ukuze kube mnye kuphela umamkeli wasekhaya ofikelela kwistratum 2 okanye 3. Emva koko baqwalasela iindawo eziseleyo kuthungelwano ukusebenzisa indawo yendawo. umncedisi wexesha. Kwimeko yenethiwekhi yam yasekhaya, lo ngumaleko wesi-3 somncedisi.
Umiliselo olwahlukeneyo lwe-NTP
Uzalisekiso lokuqala lwe-NTP yi-ntpd. Yadityaniswa ke ezimbini ezintsha, i-chronyd kunye ne-systemd-timesyncd. Zontathu zingqamanisa ixesha lenginginya lendawo kunye neseva yexesha le-NTP. Inkonzo ye-systemd-timesyncd ayithembekanga njenge-chronyd, kodwa ilungile ngokwaneleyo kwiinjongo ezininzi. Ukuba i-RTC ayisebenzi ngaxeshanye, inokuhlengahlengisa kancinane ixesha lenkqubo ukungqamanisa nomncedisi we-NTP xa ixesha lenkqubo yendawo likhukuliseka kancinane. Inkonzo ye-systemd-timesync ayinakusetyenziswa njengeseva yexesha.
kukuphunyezwa kwe-NTP equlathe iinkqubo ezimbini: i-chronyd daemon kunye nojongano lwelayini yomyalelo ebizwa ngokuba yichronyc. I-Chrony ineempawu ezithile eziyimfuneko kwiimeko ezininzi:
- I-Chrony inokwenza ngaxeshanye neseva yexesha ngokukhawuleza kunenkonzo endala ye-ntpd. Oku kulungile kwiilaptops okanye kwiidesktop ezingasebenzi ngalo lonke ixesha.
- Iyakwazi ukubuyisela ukuguquguquka kwewotshi, njengaxa umamkeli esiya kulala okanye engena kwimowudi yokulala, okanye xa iwotshi itshintsha ngenxa yokutsiba rhoqo, okuthoba iwotshi kwimithwalo ephantsi.
- Isombulula iingxaki zexesha ezinxulumene noqhagamshelo lwenethiwekhi olungazinzanga okanye ukuxinana kwenethiwekhi.
- Ilawula ukulibaziseka kwenethiwekhi.
- Emva kwexesha lokuqala ungqamaniso, Chrony akayeki iwotshi. Oku kubonelela ngamaxesha azinzileyo kwaye angaguquguqukiyo kwiinkonzo ezininzi zenkqubo kunye nezicelo.
- I-Chrony inokusebenza nangaphandle konxibelelwano lwenethiwekhi. Kule meko, umamkeli wendawo okanye umncedisi unokuhlaziywa ngesandla.
- I-Chrony inokusebenza njengeseva ye-NTP.
Kwakhona, i-NTP yiprothokholi enokuphunyezwa kumamkeli weLinux usebenzisa iChrony okanye i-systemd-timesyncd.
I-NTP, iChrony, kunye ne-systemd-timesyncd RPMs ziyafumaneka kwiindawo zokugcina zokugcina ze-Fedora. I-systemd-udev RPM ngumphathi wesiganeko se-kernel efakwe ngokungagqibekanga kwi-Fedora, kodwa iyakhethwa.
Ungazifaka zontathu kwaye utshintshe phakathi kwazo, kodwa oku kuya kudala intloko ebuhlungu eyongezelelweyo. Ngoko ke kungcono ukuba ungakwenzi. Ukukhutshwa kwangoku kwe-Fedora, i-CentOS, kunye ne-RHEL baye bafudukela kwi-Chrony njengokuphunyezwa okungagqibekanga, kwaye bane-systemd-timesyncd. Ndifumana iChrony isebenza kakuhle, ibonelela ngojongano olungcono kunenkonzo ye-NTP, ibonelela ngolwazi oluninzi kunye nolawulo, apho abalawuli benkqubo baya kuyonwabela.
Iyayekisa iiNkonzo ze-NTP
Inkonzo ye-NTP isenokuba sele isebenza kumamkeli wakho. Ukuba kunjalo, kufuneka uyicime ngaphambi kokuba utshintshele kwenye into. Ndine-chronyd ebalekayo ke ndiye ndasebenzisa le miyalelo ilandelayo ukuyimisa kwaye ndiyikhubaze. Sebenzisa imiyalelo efanelekileyo yayo nayiphi na i-daemon ye-NTP oyisebenzisayo kumamkeli wakho:
[root@testvm1 ~]# systemctl disable chronyd ; systemctl stop chronyd
Removed /etc/systemd/system/multi-user.target.wants/chronyd.service.
[root@testvm1 ~]#Khangela ukuba inkonzo imisiwe kwaye ivaliwe:
[root@testvm1 ~]# systemctl status chronyd
β chronyd.service - NTP client/server
Loaded: loaded (/usr/lib/systemd/system/chronyd.service; disabled; vendor preset: enabled)
Active: inactive (dead)
Docs: man:chronyd(8)
man:chrony.conf(5)
[root@testvm1 ~]#Ukujongwa kwemeko ngaphambi kokuqalisa
Ubume bongqamaniso lwewotshi yesixokelelwano ikuvumela ukuba ubone ukuba inkonzo ye-NTP iyasebenza. Kuba awukayiqalisi i-NTP okwangoku, i-timesync-status command iya kunika ingcebiso koku:
[root@testvm1 ~]# timedatectl timesync-status
Failed to query server: Could not activate remote peer.Isicelo sesimo esithe ngqo sibonelela ngolwazi olubalulekileyo. Umzekelo, umyalelo we-timedatectl ongenangxabano okanye iinketho zenza umgangatho ongaphantsi komyalelo ngokungagqibekanga:
[root@testvm1 ~]# timedatectl status
Local time: Fri 2020-05-15 08:43:10 EDT
Universal time: Fri 2020-05-15 12:43:10 UTC
RTC time: Fri 2020-05-15 08:43:08
Time zone: America/New_York (EDT, -0400)
System clock synchronized: no
NTP service: inactive
RTC in local TZ: yes
Warning: The system is configured to read the RTC time in the local time zone.
This mode cannot be fully supported. It will create various problems
with time zone changes and daylight saving time adjustments. The RTC
time is never updated, it relies on external facilities to maintain it.
If at all possible, use RTC in UTC by calling
'timedatectl set-local-rtc 0'.
[root@testvm1 ~]#Oku kuya kukunika ixesha lendawo lomkhosi wakho, ixesha le-UTC, kunye nexesha le-RTC. Kule meko, ixesha lenkqubo limiselwe kwi-America / New_York (TZ) ixesha lommandla, i-RTC imiselwe kwixesha lendawo yexesha lendawo, kwaye inkonzo ye-NTP ayisebenzi. Ixesha le-RTC liqalile ukutenxa kancinci kwixesha lenkqubo. Oku kuqhelekile kwimixokelelwano enewotshi engakhange idityaniswe. Umyinge we-offset kumamkeli uxhomekeke kwixesha eligqithileyo ukusukela oko yagqityelwa ukwenziwa ngaxeshanye inkqubo.
Sikwafumene isilumkiso malunga nokusebenzisa ixesha lasekuhlaleni kwi-RTC - oku kusebenza kutshintsho lwendawo yexesha kunye noseto lwe-DST. Ukuba ikhomputha ivaliwe xa kufuneka kwenziwe utshintsho, i-RTC ayiyi kutshintsha. Kodwa kwiiseva okanye ezinye iinginginya ezihamba ubusuku nemini, oku akuyongxaki kwaphela. Ukongeza, nayiphi na inkonzo ebonelela ngongqamaniso lwexesha le-NTP iya kulungelelanisa ixesha lomninimzi ngexesha lesigaba sokuqala sokuqalisa, ngoko ixesha liya kuchaneka kwakhona emva kokuba ukuqaliswa kugqityiwe.
Ukuseta izowuni yexesha
Ngokuqhelekileyo, uchaza indawo yexesha ngexesha lenkqubo yokufakela kwaye awunawo umsebenzi wokuyitshintsha kamva. Nangona kunjalo, kukho amaxesha apho kufuneka utshintshe indawo yexesha. Kukho izixhobo ezininzi ezinokunceda. I-Linux isebenzisa iifayile zommandla wexesha ukumisela izowuni yexesha lendawo yenginginya. Ezi fayile zikuluhlu /usr/share/zoneinfo. Ngokungagqibekanga, kwindawo yam yexesha, inkqubo imisela oku: /etc/localtime -> ../usr/share/zoneinfo/America/New_York. Kodwa awudingi ukwazi ubuqili obunjalo ukutshintsha indawo yexesha.
Into ephambili kukuba ukwazi igama lexesha elisemthethweni lendawo yakho kunye nomyalelo ohambelanayo. Masithi ufuna ukutshintsha indawo yexesha libe yiLos Angeles:
[root@testvm2 ~]# timedatectl list-timezones | column
<SNIP>
America/La_Paz Europe/Budapest
America/Lima Europe/Chisinau
America/Los_Angeles Europe/Copenhagen
America/Maceio Europe/Dublin
America/Managua Europe/Gibraltar
America/Manaus Europe/Helsinki
<SNIP>Ngoku unokuseta izowuni yexesha. Ndisebenzise umyalelo womhla ukujonga utshintsho, kodwa ungasebenzisa i-timedatectl:
[root@testvm2 ~]# date
Tue 19 May 2020 04:47:49 PM EDT
[root@testvm2 ~]# timedatectl set-timezone America/Los_Angeles
[root@testvm2 ~]# date
Tue 19 May 2020 01:48:23 PM PDT
[root@testvm2 ~]#Ngoku ungatshintsha indawo yexesha lomamkeli wakho ubuyele kwixesha lasekuhlaleni.
systemd-timesyncd
I-systemd timesync daemon ibonelela ngokuphunyezwa kwe-NTP ekulula ukuyilawula kumxholo wenkqubo. Ifakwe ngokungagqibekanga kwi-Fedora kunye no-Ubuntu. Nangona kunjalo, iqala ngokungagqibekanga ku-Ubuntu. Andiqinisekanga malunga nolunye unikezelo. Unokuzijonga:
[root@testvm1 ~]# systemctl status systemd-timesyncdUkuqwalasela i-systemd-timesyncd
Ifayile yoqwalaselo ye-systemd-timesyncd yi /etc/systemd/timesyncd.conf. Le yifayile elula enokhetho olumbalwa olwenziweyo kuneNTP endala kunye neenkonzo zekhronyd. Nantsi imixholo yale fayile (ngaphandle kolunye uhlengahlengiso) kwiFedora VM yam:
# This file is part of systemd.
#
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# Entries in this file show the compile time defaults.
# You can change settings by editing this file.
# Defaults can be restored by simply deleting this file.
#
# See timesyncd.conf(5) for details.
[Time]
#NTP=
#FallbackNTP=0.fedora.pool.ntp.org 1.fedora.pool.ntp.org 2.fedora.pool.ntp.org 3.fedora.pool.ntp.org
#RootDistanceMaxSec=5
#PollIntervalMinSec=32
#PollIntervalMaxSec=2048Ekuphela kwecandelo eliquletheyo, ngaphandle kwamagqabaza, lelithi [Ixesha]. Yonke eminye imigca iphawuliwe. La ngamaxabiso angagqibekanga kwaye akufuneki atshintshwe (ngaphandle kokuba unesizathu soku). Ukuba awunayo iseva yexesha le-NTP echazwe kumgca we-NTP=, i-Fedora ayigqibekanga kumncedisi wexesha we-Fedora. Ndihlala ndongeza iseva yam yexesha:
NTP=myntpserverIsebenza ngexeshasync
Ungaqala kwaye wenze i-systemd-timesyncd isebenze ngolu hlobo:
[root@testvm2 ~]# systemctl enable systemd-timesyncd.service
Created symlink /etc/systemd/system/dbus-org.freedesktop.timesync1.service β /usr/lib/systemd/system/systemd-timesyncd.service.
Created symlink /etc/systemd/system/sysinit.target.wants/systemd-timesyncd.service β /usr/lib/systemd/system/systemd-timesyncd.service.
[root@testvm2 ~]# systemctl start systemd-timesyncd.service
[root@testvm2 ~]#Ukuseta iwotshi yezixhobo
Nantsi indlela imeko ejongeka ngayo emva kokusebenza kwe-timesyncd:
[root@testvm2 systemd]# timedatectl
Local time: Sat 2020-05-16 14:34:54 EDT
Universal time: Sat 2020-05-16 18:34:54 UTC
RTC time: Sat 2020-05-16 14:34:53
Time zone: America/New_York (EDT, -0400)
System clock synchronized: yes
NTP service: active
RTC in local TZ: no Ekuqaleni, umahluko phakathi kwe-RTC kunye nexesha lendawo (EDT) lingaphantsi kwesibini, kwaye ukungafani kwanda ngesinye isibini semizuzwana kwiintsuku ezimbalwa ezizayo. Kuba akukho mbono wezowuni zexesha kwi-RTC, umyalelo we-timedatectl kufuneka wenze uthelekiso ukumisela izowuni yexesha elichanekileyo. Ukuba ixesha le-RTC alihambelani ncam nexesha lasekuhlaleni, ngoko ke alihambelani nendawo yexesha lendawo.
Ndijonge ulwazi oluninzi, ndijonge imeko ye-systemd-timesync kwaye ndafumana oku:
[root@testvm2 systemd]# systemctl status systemd-timesyncd.service
β systemd-timesyncd.service - Network Time Synchronization
Loaded: loaded (/usr/lib/systemd/system/systemd-timesyncd.service; enabled; vendor preset: disabled)
Active: active (running) since Sat 2020-05-16 13:56:53 EDT; 18h ago
Docs: man:systemd-timesyncd.service(8)
Main PID: 822 (systemd-timesyn)
Status: "Initial synchronization to time server 163.237.218.19:123 (2.fedora.pool.ntp.org)."
Tasks: 2 (limit: 10365)
Memory: 2.8M
CPU: 476ms
CGroup: /system.slice/systemd-timesyncd.service
ββ822 /usr/lib/systemd/systemd-timesyncd
May 16 09:57:24 testvm2.both.org systemd[1]: Starting Network Time Synchronization...
May 16 09:57:24 testvm2.both.org systemd-timesyncd[822]: System clock time unset or jumped backwards, restoring from recorded timestamp: Sat 2020-05-16 13:56:53 EDT
May 16 13:56:53 testvm2.both.org systemd[1]: Started Network Time Synchronization.
May 16 13:57:56 testvm2.both.org systemd-timesyncd[822]: Initial synchronization to time server 163.237.218.19:123 (2.fedora.pool.ntp.org).
[root@testvm2 systemd]#Qaphela umyalezo welog othi ixesha lenkqubo alimiselwanga okanye lisetyenzisiwe. Inkonzo yeTimesync icwangcisa ixesha lenkqubo ngokusekelwe kwisitampu sexesha. Izitampu zexesha zigcinwa yi-timesync daemon kwaye zenziwe kulo lonke ungqamaniso oluyimpumelelo.
Umyalelo we-timedatectl awunandlela yokuthatha ixabiso lewotshi yehardware kwiwotshi yenkqubo. Iseta kuphela ixesha kunye nomhla ukusuka kwixabiso elifakwe kumgca womyalelo. Unokuseta i-RTC kwixabiso elifanayo njengexesha lenkqubo usebenzisa umyalelo we-hwclock:
[root@testvm2 ~]# /sbin/hwclock --systohc --localtime
[root@testvm2 ~]# timedatectl
Local time: Mon 2020-05-18 13:56:46 EDT
Universal time: Mon 2020-05-18 17:56:46 UTC
RTC time: Mon 2020-05-18 13:56:46
Time zone: America/New_York (EDT, -0400)
System clock synchronized: yes
NTP service: active
RTC in local TZ: yesI --localtime ukhetho uxelela iwotshi yehardware ukubonisa ixesha lasekuhlaleni, hayi i-UTC.
Kutheni ufuna i-RTC kwaphela?
Nakuphi na ukuphunyezwa kwe-NTP kuyakuseta iwotshi yesixokelelwano ngexesha lokuqalisa. Kwaye kutheni ke i-RTC? Oku akuyonyani ngokupheleleyo: oku kuya kwenzeka kuphela ukuba unonxibelelwano lwenethiwekhi kwiseva yexesha. Nangona kunjalo, iinkqubo ezininzi azisoloko zikwazi ukufikelela kuqhagamshelwano lwenethiwekhi, ngoko ke iwotshi yehardware iluncedo kwiLinux ukuseta ixesha lenkqubo. Oku kungcono kunokuseta ixesha ngesandla, nangona linokutenxa kwixesha lokwenyani.
isiphelo
Eli nqaku lihlole ezinye izixhobo zokukhohlisa umhla, ixesha kunye nemimandla yexesha. Isixhobo se-systemd-timesyncd sibonelela ngomxhasi we-NTP onokungqamanisa ixesha kwinginginya yobulali ngomncedisi we-NTP. Nangona kunjalo, i-systemd-timesyncd ayiboneleli ngenkonzo yeseva, ke ukuba ufuna iseva ye-NTP kumsebenzi womnatha wakho, kufuneka usebenzise enye into, njengeChrony, ukuze usebenze njengomncedisi.
Ndikhetha ukuba nokuphunyezwa okukodwa kuyo nayiphi na inkonzo kwinethiwekhi yam, ngoko ndisebenzisa iChrony. Ukuba awudingi iseva ye-NTP yasekuhlaleni, okanye ukuba awunangxaki ngokusebenzisa iChrony njengomncedisi kunye ne-systemd-timesyncd njengomxhasi we-SNTP. Emva kwayo yonke loo nto, akukho mfuneko yokusebenzisa iimpawu ezongezelelweyo zeChrony njengomthengi ukuba wanelisekile ngumsebenzi we-systemd-timesyncd.
Elinye inqaku: awufunwa ukuba usebenzise izixhobo ze-systemd ukuphumeza i-NTP. Ungasebenzisa uguqulelo oludala lwe-ntpd, Chrony, okanye olunye umiselo lwe-NTP. Ngapha koko, i-systemd inenani elikhulu leenkonzo; uninzi lwazo lunokuzikhethela, ngoko ungazicima kwaye usebenzise enye into endaweni yoko. Oku akusiyo i-monster enkulu ye-monolithic. Awunakuyithanda inkqubo okanye iinxalenye zayo, kodwa kuya kufuneka wenze isigqibo esinolwazi.
Ndiyathanda ukuphunyezwa kwe-NTP kwe-systemd, kodwa ndikhetha iChrony kuba ifanele iimfuno zam ngcono. YiLinux, mntwana -)
Njengentengiso
VDSina inikeza , ukhetho olukhulu lweenkqubo zokusebenza zofakelo oluzenzekelayo, kunokwenzeka ukufaka nayiphi na i-OS evela kuwe , ukhululekile uphuhliso kunye nentlawulo yemihla ngemihla. Khumbula ukuba sineeseva zanaphakade ezingaphelelwa lixesha π
umthombo: www.habr.com