{"id":37723,"date":"2019-10-31T22:19:20","date_gmt":"2019-10-31T19:19:20","guid":{"rendered":"https:\/\/prohoster.info\/blog\/trening-cisco-200-125-ccna-v3-0-den-29-pat-i-nat\/"},"modified":"2019-10-31T22:19:20","modified_gmt":"2019-10-31T19:19:20","slug":"trening-cisco-200-125-ccna-v3-0-den-29-pat-i-nat","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/trening-cisco-200-125-ccna-v3-0-den-29-pat-i-nat","title":{"rendered":"\u0160kolen\u00ed Cisco 200-125 CCNA v3.0. Den 29. PAT a NAT","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Dnes se budeme zab\u00fdvat PAT (P\u0159eklad adresy portu), technologi\u00ed p\u0159ekladu IP adres pomoc\u00ed port\u016f, a NAT (P\u0159eklad s\u00ed\u0165ov\u00e9 adresy), technologi\u00ed p\u0159ekladu IP adres pr\u016fchoz\u00edch paket\u016f. PAT je zvl\u00e1\u0161tn\u00edm p\u0159\u00edpadem NAT. Probereme t\u0159i t\u00e9mata: <\/p>\n

\u2014 soukrom\u00e9, nebo vnit\u0159n\u00ed (lok\u00e1ln\u00ed) IP adresy a ve\u0159ejn\u00e9, nebo extern\u00ed IP adresy;
\n \u2014 NAT a PAT;
\n \u2014 nastaven\u00ed NAT\/PAT.<\/p>\n

Za\u010dn\u011bme s intern\u00edmi adresami Private IP. V\u00edme, \u017ee se d\u011bl\u00ed do t\u0159\u00ed t\u0159\u00edd: A, B a C. <\/p>\n

\"\u0160kolen\u00ed
\n
\nIntern\u00ed adresy t\u0159\u00eddy A zab\u00edraj\u00ed rozsah \"des\u00edtky\" od 10.0.0.0 do 10.255.255.255, zat\u00edmco extern\u00ed \u2014 rozsah od 1.0.0.0 do 9.255.255.255 a od 11.0.0.0 do 126.255.255.255. <\/p>\n

Intern\u00ed adresy t\u0159\u00eddy B zab\u00edraj\u00ed rozsah od 172.16.0.0 do 172.31.255.255, zat\u00edmco extern\u00ed \u2014 od 128.0.0.0 do 172.15.255.255 a od 172.32.0.0 do 191.255.255.255.<\/a><\/noindex><\/p>\n

Intern\u00ed adresy t\u0159\u00eddy C zab\u00edraj\u00ed rozsah od 192.168.0.0 do 192.168.255.255, zat\u00edmco extern\u00ed \u2014 od 192.0.0 do 192.167.255.255 a od 192.169.0.0 do 223.255.255.255.<\/p>\n

\"\u0160kolen\u00ed
\n
\nAdresy t\u0159\u00eddy A maj\u00ed prefix \/8, t\u0159\u00eddy B \u2014 \/12 a t\u0159\u00eddy C \u2014 \/16. Tak\u017ee extern\u00ed a intern\u00ed IP adresy r\u016fzn\u00fdch t\u0159\u00edd zab\u00edraj\u00ed r\u016fzn\u00e9 rozsahy. <\/p>\n

Opakovan\u011b jsme diskutovali o tom, jak\u00fd je rozd\u00edl mezi soukrom\u00fdmi a ve\u0159ejn\u00fdmi IP adresami. Obecn\u011b, pokud m\u00e1me sm\u011brova\u010d a skupinu intern\u00edch IP adres, p\u0159i pokusu o jejich p\u0159ipojen\u00ed k internetu sm\u011brova\u010d je p\u0159evede na extern\u00ed IP adresy. Intern\u00ed adresy se pou\u017e\u00edvaj\u00ed pouze v lok\u00e1ln\u00edch s\u00edt\u00edch, a ne na internetu. <\/p>\n

Pokud se pod\u00edv\u00e1m na s\u00ed\u0165ov\u00e9 parametry sv\u00e9ho po\u010d\u00edta\u010de pomoc\u00ed p\u0159\u00edkazov\u00e9ho \u0159\u00e1dku, uvid\u00edm tam svou intern\u00ed LAN IP adresu 192.168.1.103.<\/p>\n

\"\u0160kolen\u00ed
\n
\nK tomu, abych zjistil svou ve\u0159ejnou IP adresu, mohu vyu\u017e\u00edt internetovou slu\u017ebu typu \"Jak\u00e1 je moje IP?\" Jak vid\u00edte, extern\u00ed adresa po\u010d\u00edta\u010de 78.100.196.163 se li\u0161\u00ed od jeho intern\u00ed adresy. <\/p>\n

\"\u0160kolen\u00ed
\n
\nVe v\u0161ech p\u0159\u00edpadech je m\u016fj po\u010d\u00edta\u010d na internetu viditeln\u00fd pr\u00e1v\u011b d\u00edky extern\u00ed IP adrese. Tak\u017ee, intern\u00ed adresa m\u00e9ho po\u010d\u00edta\u010de je 192.168.1.103 a extern\u00ed \u2014 78.100.196.163. Intern\u00ed adresa se pou\u017e\u00edv\u00e1 pouze pro lok\u00e1ln\u00ed komunikaci, s n\u00ed nelze p\u0159istupovat na internet, k tomu pot\u0159ebujete ve\u0159ejnou IP adresu. M\u016f\u017eete si p\u0159ipomenout, pro\u010d do\u0161lo k rozd\u011blen\u00ed na soukrom\u00e9 a ve\u0159ejn\u00e9 adresy, zhl\u00e9dnut\u00edm videa Den 3. <\/p>\n

Pod\u00edvejme se, co je NAT. Existuj\u00ed t\u0159i typy NAT: statick\u00fd, dynamick\u00fd a \"p\u0159epln\u011bn\u00fd\" NAT, nebo PAT.<\/p>\n

\"\u0160kolen\u00ed
\n
\nVe spole\u010dnosti Cisco existuj\u00ed \u010dty\u0159i term\u00edny popisuj\u00edc\u00ed NAT. Jak jsem ji\u017e zm\u00ednil, NAT je mechanismus, kter\u00fd p\u0159etv\u00e1\u0159\u00ed intern\u00ed adresy na extern\u00ed. Pokud za\u0159\u00edzen\u00ed p\u0159ipojen\u00e9 k internetu obdr\u017e\u00ed paket od jin\u00e9ho za\u0159\u00edzen\u00ed v m\u00edstn\u00ed s\u00edti, jednodu\u0161e ho odm\u00edtne, proto\u017ee form\u00e1t intern\u00ed adresy neodpov\u00edd\u00e1 form\u00e1tu adres pou\u017e\u00edvan\u00fdch v glob\u00e1ln\u00ed s\u00edti Internetu. Proto za\u0159\u00edzen\u00ed mus\u00ed z\u00edskat ve\u0159ejnou IP adresu pro p\u0159\u00edstup na internet.
\nPrvn\u00ed term\u00edn je Inside Local, co\u017e znamen\u00e1 IP adresu hostitele v intern\u00ed, m\u00edstn\u00ed s\u00edti. Jin\u00fdmi slovy, je to prim\u00e1rn\u00ed adresa zdroje typu 192.168.1.10. Druh\u00fd term\u00edn, Inside Global, p\u0159edstavuje IP adresu m\u00edstn\u00edho hostitele, pod kterou je viditeln\u00fd v extern\u00ed s\u00edti. V na\u0161em p\u0159\u00edpad\u011b je to IP adresa extern\u00edho portu routeru 200.124.22.10.<\/p>\n

\"\u0160kolen\u00ed
\n
\nLze \u0159\u00edci, \u017ee Inside Local je soukrom\u00e1 IP adresa, zat\u00edmco Inside Global je ve\u0159ejn\u00e1 IP adresa. Pamatujte, \u017ee term\u00edn Inside se pou\u017e\u00edv\u00e1 ve vztahu k zdroji provozu, zat\u00edmco Outside k c\u00edli provozu. Outside Local je IP adresa hostitele v extern\u00ed s\u00edti, pod kterou je viditeln\u00fd pro intern\u00ed s\u00ed\u0165. Jin\u00fdmi slovy, je to adresa p\u0159\u00edjemce, viditeln\u00e1 z intern\u00ed s\u00edt\u011b. P\u0159\u00edklad takov\u00e9 adresy je IP adresa 200.124.22.100 za\u0159\u00edzen\u00ed um\u00edst\u011bn\u00e9ho na internetu. <\/p>\n

\"\u0160kolen\u00ed
\n
\nOutside Global je IP adresa hostitele, viditeln\u00e1 v extern\u00ed s\u00edti. Ve v\u011bt\u0161in\u011b p\u0159\u00edpad\u016f se adresy Outside Local a Outside Global jev\u00ed jako toto\u017en\u00e9, proto\u017ee i po p\u0159etv\u00e1\u0159en\u00ed je IP adresa c\u00edle pro zdroj viditeln\u00e1 stejn\u00e1, jako p\u0159ed p\u0159etv\u00e1\u0159en\u00edm. <\/p>\n

\"\u0160kolen\u00ed
\n
\nPod\u00edvejme se, co p\u0159edstavuje statick\u00fd NAT. Statick\u00fd NAT znamen\u00e1 vz\u00e1jemn\u00e9 jednozna\u010dn\u00e9 p\u0159etv\u00e1\u0159en\u00ed intern\u00edch IP adres na extern\u00ed, \u010di p\u0159etv\u00e1\u0159en\u00ed \"jeden na jednoho\". Kdy\u017e za\u0159\u00edzen\u00ed odes\u00edlaj\u00ed provoz na Internet, jejich intern\u00ed adresy Inside Local se p\u0159etv\u00e1\u0159ej\u00ed na intern\u00ed adresy Inside Global.<\/p>\n

\"\u0160kolen\u00ed
\n
\nV na\u0161\u00ed m\u00edstn\u00ed s\u00edti jsou t\u0159i za\u0159\u00edzen\u00ed, a kdy\u017e se chystaj\u00ed vstoupit do internetu, ka\u017ed\u00e9 z nich z\u00edsk\u00e1 svou vlastn\u00ed adresu Inside Global. Tyto adresy jsou staticky p\u0159i\u0159azeny k zdroj\u016fm provozu. Princip \"jeden na jednoho\" znamen\u00e1, \u017ee pokud je v m\u00edstn\u00ed s\u00edti um\u00edst\u011bno 100 za\u0159\u00edzen\u00ed, z\u00edskaj\u00ed 100 extern\u00edch adres. <\/p>\n

NAT vznikl, aby zachr\u00e1nil internet, kde doch\u00e1zelo k vy\u010derp\u00e1n\u00ed ve\u0159ejn\u00fdch IP adres. D\u00edky NAT m\u016f\u017ee m\u00edt mnoho spole\u010dnost\u00ed a s\u00edt\u00ed jednu spole\u010dnou ve\u0159ejnou IP adresu, na kterou se p\u0159ev\u00e1d\u011bj\u00ed m\u00edstn\u00ed adresy za\u0159\u00edzen\u00ed p\u0159i p\u0159ipojen\u00ed k internetu. M\u016f\u017eete \u0159\u00edci, \u017ee v tomto p\u0159\u00edpad\u011b statick\u00fd NAT nenab\u00edz\u00ed \u017e\u00e1dnou \u00fasporu po\u010dtu adres, proto\u017ee sto m\u00edstn\u00edch po\u010d\u00edta\u010d\u016f dost\u00e1v\u00e1 sto ve\u0159ejn\u00fdch adres, a budete naprosto spr\u00e1vn\u00ed. Nicm\u00e9n\u011b, statick\u00fd NAT m\u00e1 st\u00e1le \u0159adu v\u00fdhod.<\/p>\n

Nap\u0159\u00edklad m\u00e1me server s vnit\u0159n\u00ed IP adresou 192.168.1.100. Pokud se n\u011bjak\u00e9 za\u0159\u00edzen\u00ed z internetu pokus\u00ed s n\u00edm spojit, nebude to moci ud\u011blat, pokud pou\u017eije vnit\u0159n\u00ed c\u00edlovou adresu, pro to mus\u00ed pou\u017e\u00edt ve\u0159ejnou adresu serveru 200.124.22.3. Pokud je na routeru nastaven statick\u00fd NAT, ve\u0161ker\u00fd provoz sm\u011b\u0159uj\u00edc\u00ed na 200.124.22.3 je automaticky p\u0159eposl\u00e1n na 192.168.1.100. T\u00edm je zaji\u0161t\u011bn extern\u00ed p\u0159\u00edstup k za\u0159\u00edzen\u00edm v lok\u00e1ln\u00ed s\u00edti, v tomto p\u0159\u00edpad\u011b k webov\u00e9mu serveru spole\u010dnosti, co\u017e m\u016f\u017ee b\u00fdt v ur\u010dit\u00fdch p\u0159\u00edpadech nezbytn\u00e9. <\/p>\n

Pod\u00edvejme se na dynamick\u00fd NAT. Je velmi podobn\u00fd statick\u00e9mu, ale nep\u0159id\u011bluje trval\u00e9 ve\u0159ejn\u00e9 adresy ka\u017ed\u00e9mu m\u00edstn\u00edmu za\u0159\u00edzen\u00ed. Nap\u0159\u00edklad m\u00e1me 3 m\u00edstn\u00ed za\u0159\u00edzen\u00ed a pouze 2 ve\u0159ejn\u00e9 adresy. Pokud se druh\u00e9 za\u0159\u00edzen\u00ed pokus\u00ed vyj\u00edt na internet, bude mu p\u0159id\u011blena prvn\u00ed dostupn\u00e1 IP adresa. Pokud pot\u00e9 webov\u00fd server chce vyj\u00edt na internet, router mu p\u0159i\u0159ad\u00ed druhou dostupnou ve\u0159ejnou adresu. Pokud se pot\u00e9 prvn\u00edm za\u0159\u00edzen\u00edm pokus\u00ed vyj\u00edt do extern\u00ed s\u00edt\u011b, nebudou pro n\u011bj k dispozici \u017e\u00e1dn\u00e9 IP adresy, a router jeho paket zahod\u00ed. <\/p>\n

\"\u0160kolen\u00ed
\n
\nM\u016f\u017eeme m\u00edt stovku za\u0159\u00edzen\u00ed s vnit\u0159n\u00edmi IP adresami a ka\u017ed\u00e9 z t\u011bchto za\u0159\u00edzen\u00ed se m\u016f\u017ee p\u0159ipojit k internetu. Ale proto\u017ee nem\u00e1me statick\u00e9 p\u0159i\u0159azen\u00ed ve\u0159ejn\u00fdch adres, m\u016f\u017ee se najednou p\u0159ipojit k internetu maxim\u00e1ln\u011b 2 za\u0159\u00edzen\u00ed z t\u00e9to stovky, proto\u017ee m\u00e1me pouze dv\u011b dynamicky p\u0159id\u011blovan\u00e9 ve\u0159ejn\u00e9 adresy. <\/p>\n

Za\u0159\u00edzen\u00ed Cisco maj\u00ed stanovenou dobu p\u0159eklad\u016f adres, kter\u00e1 je ve v\u00fdchoz\u00edm nastaven\u00ed 24 hodin. Tuto dobu lze zm\u011bnit na 1, 2, 3, 10 minut nebo na jak\u00fdkoliv jin\u00fd po\u017eadovan\u00fd \u010das. Po uplynut\u00ed t\u00e9to doby se extern\u00ed adresy uvol\u0148uj\u00ed a automaticky se vracej\u00ed do z\u00e1sobn\u00edku adres. Pokud v tuto chv\u00edli prvn\u00ed za\u0159\u00edzen\u00ed chce p\u0159istoupit k internetu a n\u011bjak\u00e1 extern\u00ed adresa je dostupn\u00e1, pak ji z\u00edsk\u00e1. Router obsahuje NAT tabulku, kter\u00e1 se dynamicky aktualizuje, a dokud \u010das p\u0159eklad\u016f nevypr\u0161el, ur\u010den\u00e1 adresa je rezervov\u00e1na pro za\u0159\u00edzen\u00ed. Jin\u00fdmi slovy, dynamick\u00fd NAT funguje na principu: \u201ekdo p\u0159i\u0161el prvn\u00ed, toho obslou\u017eili.\u201c <\/p>\n

Pod\u00edvejme se, co p\u0159edstavuje p\u0159et\u00ed\u017een\u00fd NAT, neboli PAT. To je nejb\u011b\u017en\u011bj\u0161\u00ed typ NAT. Ve va\u0161\u00ed dom\u00e1c\u00ed s\u00edti m\u016f\u017ee b\u00fdt mnoho za\u0159\u00edzen\u00ed \u2013 PC, smartphone, notebook, tablet \u2013 a v\u0161echna se p\u0159ipojuj\u00ed k routeru, kter\u00fd m\u00e1 jednu extern\u00ed IP adresu. PAT umo\u017e\u0148uje mnoha za\u0159\u00edzen\u00edm s vnit\u0159n\u00edmi IP adresami sou\u010dasn\u011b p\u0159istupovat k internetu pod jednou extern\u00ed IP adresou. To je mo\u017en\u00e9 d\u00edky tomu, \u017ee ka\u017ed\u00e1 priv\u00e1tn\u00ed, vnit\u0159n\u00ed IP adresa pou\u017e\u00edv\u00e1 b\u011bhem relace ur\u010dit\u00e9 \u010d\u00edslo portu.
\nP\u0159edpokl\u00e1dejme, \u017ee m\u00e1me jednu ve\u0159ejnou adresu 200.124.22.1 a mnoho m\u00edstn\u00edch za\u0159\u00edzen\u00ed. P\u0159i p\u0159\u00edstupu na internet v\u0161echny tyto hostitele z\u00edskaj\u00ed tut\u00e9\u017e adresu 200.124.22.1. Jedin\u00e9, co je bude od sebe odli\u0161ovat, je \u010d\u00edslo portu.
\nPokud si pamatujete diskusi o transportn\u00ed \u00farovni, v\u00edte, \u017ee transportn\u00ed \u00farove\u0148 obsahuje \u010d\u00edsla port\u016f, p\u0159i\u010dem\u017e \u010d\u00edslo portu zdroje p\u0159edstavuje n\u00e1hodn\u00e9 \u010d\u00edslo. <\/p>\n

\"\u0160kolen\u00ed
\n
\nP\u0159edpokl\u00e1dejme, \u017ee vn\u011bj\u0161\u00ed s\u00ed\u0165 m\u00e1 hostitele s IP adresou 200.124.22.10, kter\u00fd je p\u0159ipojen k internetu. Pokud se po\u010d\u00edta\u010d 192.168.1.11 chce spojit s po\u010d\u00edta\u010dem 200.124.22.10, vytvo\u0159\u00ed n\u00e1hodn\u00fd port zdroje 51772. Port ur\u010den\u00ed v po\u010d\u00edta\u010di vn\u011bj\u0161\u00ed s\u00edt\u011b bude 80. <\/p>\n

Kdy\u017e router obdr\u017e\u00ed paket m\u00edstn\u00edho po\u010d\u00edta\u010de, sm\u011b\u0159uj\u00edc\u00ed do vn\u011bj\u0161\u00ed s\u00edt\u011b, p\u0159elo\u017e\u00ed jeho lok\u00e1ln\u00ed adresu Inside Local na adresu Inside Global 200.124.22.1 a p\u0159i\u0159ad\u00ed portu \u010d\u00edslo 23556. Paket dos\u00e1hne po\u010d\u00edta\u010de 200.124.22.10, a ten bude muset odeslat zp\u011bt odpov\u011b\u010f podle postupn\u00e9ho protokolu, p\u0159i\u010dem\u017e ur\u010den\u00edm bude adresa 200.124.22.1 a port 23556. <\/p>\n

Router m\u00e1 NAT p\u0159ekladovou tabulku, tak\u017ee kdy\u017e obdr\u017e\u00ed paket z extern\u00edho po\u010d\u00edta\u010de, ur\u010d\u00ed Inside Local adresu odpov\u00eddaj\u00edc\u00ed Inside Global adrese jako 192.168.1.11: 51772 a p\u0159epo\u0161le mu paket. Po tomto kroku lze pova\u017eovat spojen\u00ed mezi dv\u011bma po\u010d\u00edta\u010di za nav\u00e1zan\u00e9.
\nVe stejnou dobu m\u016f\u017eete m\u00edt sto za\u0159\u00edzen\u00ed, kter\u00e1 pou\u017e\u00edvaj\u00ed pro komunikaci stejnou adresu 200.124.22.1, ale r\u016fzn\u00e9 \u010d\u00edsla port\u016f, co\u017e jim umo\u017e\u0148uje v\u0161echny sou\u010dasn\u011b se p\u0159ipojit k internetu. To je d\u016fvod, pro\u010d je PAT tak popul\u00e1rn\u00ed metodou p\u0159eklad\u016f.<\/p>\n

Poj\u010fme se pod\u00edvat na nastaven\u00ed statick\u00e9ho NAT. Pro ka\u017edou s\u00ed\u0165 je nejprve nutn\u00e9 ur\u010dit vstupn\u00ed a v\u00fdstupn\u00ed rozhran\u00ed. Na sch\u00e9matu je zobrazen router, kter\u00fd p\u0159en\u00e1\u0161\u00ed provoz z portu G0\/0 na port G0\/1, tedy z vnit\u0159n\u00ed s\u00edt\u011b do vn\u011bj\u0161\u00ed s\u00edt\u011b. Tak m\u00e1me vstupn\u00ed rozhran\u00ed 192.168.1.1 a v\u00fdstupn\u00ed rozhran\u00ed 200.124.22.1. <\/p>\n

\"\u0160kolen\u00ed
\n
\nPro nastaven\u00ed NAT p\u0159ejdeme k rozhran\u00ed G0\/0 a zad\u00e1me parametry ip address 192.168.1.1 255.255.255.0 a ur\u010d\u00edme, \u017ee toto rozhran\u00ed je vstupn\u00ed pomoc\u00ed p\u0159\u00edkazip nat inside. <\/p>\n

\"\u0160kolen\u00ed
\n
\nPodobn\u00fdm zp\u016fsobem nastav\u00edme NAT na v\u00fdstupn\u00edm rozhran\u00ed G0\/1, p\u0159i\u010dem\u017e uvedeme ip address 200.124.22.1, masku pods\u00edt\u011b 255.255.255.0 a ip nat outside. Pamatujte, \u017ee p\u0159echod dynamick\u00e9ho NAT v\u017edy prob\u00edh\u00e1 od vstupn\u00edho k v\u00fdstupn\u00edmu rozhran\u00ed, od inside k outside. Samoz\u0159ejm\u011b, \u017ee pro dynamick\u00fd NAT odpov\u011b\u010f p\u0159ich\u00e1z\u00ed na vstupn\u00ed rozhran\u00ed p\u0159es v\u00fdstupn\u00ed, ale p\u0159i iniciaci provozu je to sm\u011br in-out. U statick\u00e9ho NAT m\u016f\u017ee iniciace provozu prob\u00edhat v obou sm\u011brech \u2013 in-out nebo out-in. <\/p>\n

D\u00e1le pot\u0159ebujeme sestavit tabulku statick\u00e9ho NAT, kde ka\u017ed\u00e9 lok\u00e1ln\u00ed adrese odpov\u00edd\u00e1 samostatn\u00e1 glob\u00e1ln\u00ed adresa. V na\u0161em p\u0159\u00edpad\u011b m\u00e1me 3 za\u0159\u00edzen\u00ed, tak\u017ee tabulka bude sest\u00e1vat ze 3 z\u00e1znam\u016f, ve kter\u00fdch je uvedena Inside Local IP adresa zdroje, kter\u00e1 se p\u0159ev\u00e1d\u00ed na Inside Global adresu: ip nat inside static 192.168.1.10 200.124.22.1.
\nT\u00edmto zp\u016fsobem v statick\u00e9m NAT ru\u010dn\u011b definujete p\u0159evod pro ka\u017edou adresu m\u00edstn\u00edho hostitele. Nyn\u00ed p\u0159ejdu na Packet Tracer a provedu v\u00fd\u0161e uveden\u00e9 nastaven\u00ed. <\/p>\n

\"\u0160kolen\u00ed
\n
\nNa vrchu m\u00e1me server 192.168.1.100, pod n\u00edm se nach\u00e1z\u00ed po\u010d\u00edta\u010d 192.168.1.10 a \u00fapln\u011b dole je po\u010d\u00edta\u010d 192.168.1.11. Port G0\/0 routeru Router0 m\u00e1 IP adresu 192.168.1.1 a port G0\/1 m\u00e1 200.124.22.1. V 'cloudu', kter\u00fd zn\u00e1zor\u0148uje internet, jsem um\u00edstil Router1, kter\u00e9mu byla p\u0159i\u0159azena IP adresa 200.124.22.10.<\/p>\n

Vstupuji do nastaven\u00ed Router1 a zad\u00e1v\u00e1m p\u0159\u00edkaz debug ip icmp. Nyn\u00ed, jakmile ping doraz\u00ed k tomuto za\u0159\u00edzen\u00ed, v okn\u011b nastaven\u00ed se objev\u00ed zpr\u00e1va o lad\u011bn\u00ed, kter\u00e1 ukazuje, o jak\u00fd paket se jedn\u00e1.
\nPust\u00edme se do nastaven\u00ed routeru Router0. P\u0159ech\u00e1z\u00edm do re\u017eimu glob\u00e1ln\u00edch nastaven\u00ed a vol\u00e1m rozhran\u00ed G0\/0. Pot\u00e9 zad\u00e1v\u00e1m p\u0159\u00edkaz ip nat inside, n\u00e1sledn\u011b p\u0159ech\u00e1z\u00edm k rozhran\u00ed g0\/1 a zad\u00e1v\u00e1m p\u0159\u00edkaz ip nat outside. Takto jsem p\u0159i\u0159adil vstupn\u00ed a v\u00fdstupn\u00ed rozhran\u00ed routeru. Nyn\u00ed mus\u00edm ru\u010dn\u011b nastavit IP adresy, tedy p\u0159ev\u00e9st do nastaven\u00ed \u0159\u00e1dky z d\u0159\u00edve uveden\u00e9 tabulky: <\/p>\n

Ip nat inside source static 192.168.1.10 200.124.22.1
\nIp nat inside source static 192.168.1.11 200.124.22.2
\nIp nat inside source static 192.168.1.100 200.124.22.3 <\/p>\n

\"\u0160kolen\u00ed
\n
\nNyn\u00ed provedu ping Router1 z ka\u017ed\u00e9ho z na\u0161ich za\u0159\u00edzen\u00ed a uvid\u00edm, jak\u00e9 IP adresy uk\u00e1\u017ee p\u0159ijat\u00fd ping. K tomu m\u00e1m otev\u0159en\u00e9 okno CLI routeru R1 na prav\u00e9 stran\u011b obrazovky, abych vid\u011bl zpr\u00e1vy o lad\u011bn\u00ed. Nyn\u00ed p\u0159ech\u00e1z\u00edm do termin\u00e1lu p\u0159\u00edkazov\u00e9ho \u0159\u00e1dku PC0 a pingnu adresu 200.124.22.10. Po tom se v okn\u011b objev\u00ed zpr\u00e1va, \u017ee ping byl p\u0159ijat z IP adresy 200.124.22.1. To znamen\u00e1, \u017ee IP adresa m\u00edstn\u00edho po\u010d\u00edta\u010de 192.168.1.10 byla p\u0159evedena na glob\u00e1ln\u00ed adresu 200.124.22.1.<\/p>\n

\"\u0160kolen\u00ed
\n
\nTot\u00e9\u017e d\u011bl\u00e1m se n\u00e1sleduj\u00edc\u00edm m\u00edstn\u00edm po\u010d\u00edta\u010dem a vid\u00edm, \u017ee jeho adresa byla p\u0159evedena na 200.124.22.2. Pot\u00e9 pos\u00edl\u00e1m ping ze serveru a vid\u00edm adresu 200.124.22.3.
\nTak\u017ee, kdy\u017e provoz z za\u0159\u00edzen\u00ed m\u00edstn\u00ed s\u00edt\u011b dos\u00e1hne routeru, na kter\u00e9m je nastaven statick\u00fd NAT, router podle tabulky p\u0159evede m\u00edstn\u00ed IP adresu na glob\u00e1ln\u00ed a ode\u0161le provoz do vn\u011bj\u0161\u00ed s\u00edt\u011b. Abych zkontroloval tabulku NAT, zad\u00e1v\u00e1m p\u0159\u00edkaz show ip nat translations.<\/p>\n

\"\u0160kolen\u00ed
\n
\nNyn\u00ed m\u016f\u017eeme prohl\u00ed\u017eet v\u0161echny transformace, kter\u00e9 router prov\u00e1d\u00ed. V prvn\u00edm sloupci Inside Global je adresa za\u0159\u00edzen\u00ed p\u0159ed translac\u00ed, co\u017e je adresa, pod kterou je za\u0159\u00edzen\u00ed viditeln\u00e9 z vn\u011bj\u0161\u00ed s\u00edt\u011b. N\u00e1sleduje adresa Inside Local, tedy adresa za\u0159\u00edzen\u00ed v lok\u00e1ln\u00ed s\u00edti. T\u0159et\u00ed sloupec ukazuje Outside Local a \u010dtvrt\u00fd sloupec uv\u00e1d\u00ed adresu Outside Global, p\u0159i\u010dem\u017e ob\u011b tyto adresy jsou shodn\u00e9, proto\u017ee nepodl\u00e9h\u00e1me transformaci IP adresy c\u00edle. Jak vid\u00edte, po n\u011bkolika sekund\u00e1ch se tabulka vy\u010distila, proto\u017ee v Packet Tracer je nastaven\u00fd kr\u00e1tk\u00fd timeout pingu. <\/p>\n

Mohu prov\u00e9st ping z routeru R1 na server na adrese 200.124.22.3, a pokud se znovu vr\u00e1t\u00edme k nastaven\u00ed routeru, m\u016f\u017eeme vid\u011bt, \u017ee tabulka se znovu naplnila \u010dty\u0159mi \u0159\u00e1dky pingu s transformovanou adresou c\u00edle 192.168.1.100.<\/p>\n

\"\u0160kolen\u00ed
\n
\nJak jsem ji\u017e \u0159ekl, i kdy\u017e dojde k timeoutu translace, p\u0159i iniciaci provozu z vn\u011bj\u0161\u00edho zdroje se mechanismus NAT automaticky aktivuje. K tomu doch\u00e1z\u00ed pouze p\u0159i pou\u017eit\u00ed statick\u00e9ho NAT. <\/p>\n

Nyn\u00ed se pod\u00edvejme, jak funguje dynamick\u00fd NAT. V na\u0161em p\u0159\u00edkladu m\u00e1me 2 ve\u0159ejn\u00e9 adresy pro t\u0159i za\u0159\u00edzen\u00ed v lok\u00e1ln\u00ed s\u00edti, av\u0161ak m\u016f\u017ee existovat des\u00edtky a stovky takov\u00fdch priv\u00e1tn\u00edch hostitel\u016f. P\u0159itom budou moci sou\u010dasn\u011b vyj\u00edt na internet pouze 2 za\u0159\u00edzen\u00ed. Pod\u00edvejme se, v \u010dem spo\u010d\u00edv\u00e1 rozd\u00edl mezi statick\u00fdm a dynamick\u00fdm NAT, krom\u011b tohoto.<\/p>\n

Stejn\u011b jako v p\u0159edchoz\u00edm p\u0159\u00edpad\u011b je nejprve t\u0159eba ur\u010dit vstupn\u00ed a v\u00fdstupn\u00ed rozhran\u00ed routeru. D\u00e1le vytv\u00e1\u0159\u00edme jak\u00fdsi p\u0159\u00edstupov\u00fd seznam, av\u0161ak to nen\u00ed ten ACL, o kter\u00e9m jsme mluvili v p\u0159edchoz\u00ed lekci. Tento p\u0159\u00edstupov\u00fd seznam se pou\u017e\u00edv\u00e1 k identifikaci provozu, kter\u00fd chceme transformovat. Zde se objevuje nov\u00fd term\u00edn 'interesting traffic', nebo 'zaj\u00edmav\u00fd provoz'. To je provoz, kter\u00fd v\u00e1s n\u011bjak\u00fdm zp\u016fsobem zaj\u00edm\u00e1, a kdy\u017e tento provoz spln\u00ed podm\u00ednky p\u0159\u00edstupov\u00e9ho seznamu, podl\u00e9h\u00e1 NAT a transformuje se. Tento term\u00edn je pou\u017eiteln\u00fd pro provoz v mnoha p\u0159\u00edpadech, nap\u0159\u00edklad v p\u0159\u00edpad\u011b VPN se 'zaj\u00edmav\u00fdm' ozna\u010duje provoz, kter\u00fd se chystaj\u00ed p\u0159en\u00e9st p\u0159es VPN tunel. <\/p>\n

Mus\u00edme vytvo\u0159it ACL, kter\u00fd identifikuje 'interesting traffic', v na\u0161em p\u0159\u00edpad\u011b je to provoz cel\u00e9 s\u00edt\u011b 192.168.1.0, p\u0159i\u010dem\u017e se ud\u00e1v\u00e1 zp\u011btn\u00e1 maska 0.0.0.255. <\/p>\n

\"\u0160kolen\u00ed
\n
\nPot\u00e9 mus\u00edme vytvo\u0159it NAT pool, k \u010demu\u017e pou\u017eijeme p\u0159\u00edkaz ip nat pool a uvedeme rozsah IP adres 200.124.22.1 200.124.22.2. To znamen\u00e1, \u017ee poskytujeme pouze dv\u011b extern\u00ed IP adresy. D\u00e1le v p\u0159\u00edkazu pou\u017eijeme kl\u00ed\u010dov\u00e9 slovo netmask a zad\u00e1me masku pods\u00edt\u011b 255.255.255.252. Posledn\u00ed oktet masky je (255 \u2014 po\u010det adres v poolu \u2013 1), tak\u017ee pokud m\u00e1te v poolu 254 adres, pak maska pods\u00edt\u011b bude 255.255.255.0. To je velmi d\u016fle\u017eit\u00fd parametr, proto p\u0159i nastavov\u00e1n\u00ed dynamick\u00e9ho NAT dbejte na to, abyste zadali spr\u00e1vnou hodnotu netmask. <\/p>\n

Pak pou\u017eijeme p\u0159\u00edkaz, kter\u00fd spust\u00ed mechanismus NAT: ip nat inside source list 1 pool NWKING, kde NWKING je n\u00e1zev poolu a list 1 znamen\u00e1 seznam p\u0159\u00edstupu ACL \u010d\u00edslo 1. Pamatujte \u2014 aby tento p\u0159\u00edkaz fungoval, je nejprve nutn\u00e9 vytvo\u0159it pool dynamick\u00fdch adres a seznam p\u0159\u00edstupu. <\/p>\n

Tak\u017ee za na\u0161ich podm\u00ednek prvn\u00ed za\u0159\u00edzen\u00ed, kter\u00e9 se pokus\u00ed p\u0159ipojit k internetu, to zvl\u00e1dne, druh\u00e9 za\u0159\u00edzen\u00ed tak\u00e9, ale t\u0159et\u00ed bude muset \u010dekat, a\u017e se uvoln\u00ed jedna z adres poolu. Nastaven\u00ed dynamick\u00e9ho NAT se skl\u00e1d\u00e1 ze 4 krok\u016f: ur\u010den\u00ed vstupn\u00edho a v\u00fdstupn\u00edho rozhran\u00ed, ur\u010den\u00ed \u201einteresantn\u00edho\u201c provozu, vytvo\u0159en\u00ed NAT poolu a vlastn\u011b samotn\u00e9 nastaven\u00ed.
\nNyn\u00ed p\u0159ejdeme k Packet Tracer a pokus\u00edme se nastavit dynamick\u00fd NAT. Nejprve mus\u00edme odstranit nastaven\u00ed statick\u00e9ho NAT, k \u010demu\u017e postupn\u011b zad\u00e1me p\u0159\u00edkazy:<\/p>\n

no Ip nat inside source static 192.168.1.10 200.124.22.1
\nno Ip nat inside source static 192.168.1.11 200.124.22.2
\nno Ip nat inside source static 192.168.1.100 200.124.22.3. <\/p>\n

D\u00e1le vytv\u00e1\u0159\u00edm seznam p\u0159\u00edstupu List 1 pro celou s\u00ed\u0165 p\u0159\u00edkazem access-list 1 permit 192.168.1.0 0.0.0.255 a formuji NAT pool pomoc\u00ed p\u0159\u00edkazu ip nat pool NWKING 200.124.22.1 200.124.22.2 netmask 255.255.255.252. V tomto p\u0159\u00edkazu jsem uvedl n\u00e1zev poolu, adresy, kter\u00e9 do n\u011bj pat\u0159\u00ed, a s\u00ed\u0165ovou masku.<\/p>\n

Pot\u00e9 ur\u010du, jak\u00fd typ NAT to je \u2013 vnit\u0159n\u00ed nebo vn\u011bj\u0161\u00ed, a zdroj, ze kter\u00e9ho by m\u011bl NAT \u010derpat informace, v na\u0161em p\u0159\u00edpad\u011b je to list, pomoc\u00ed p\u0159\u00edkazu ip nat inside source list 1. Po tomto p\u0159\u00edkazu syst\u00e9m vy\u017e\u00e1d\u00e1, zda pot\u0159ebujeme cel\u00fd pool nebo konkr\u00e9tn\u00ed rozhran\u00ed. Vol\u00edm pool, proto\u017ee m\u00e1me v\u00edce ne\u017e jednu vn\u011bj\u0161\u00ed adresu. Pokud byste zvolili rozhran\u00ed, museli byste zadat port s konkr\u00e9tn\u00ed IP adresou. V\u00fdsledn\u00fd p\u0159\u00edkaz bude vypadat takto: ip nat inside source list 1 pool NWKING. Tento pool nyn\u00ed obsahuje dv\u011b adresy 200.124.22.1 a 200.124.22.2, ale m\u016f\u017eete je voln\u011b zm\u011bnit nebo p\u0159idat nov\u00e9 adresy, kter\u00e9 nejsou v\u00e1z\u00e1ny na konkr\u00e9tn\u00ed rozhran\u00ed. <\/p>\n

Mus\u00edte se ujistit, \u017ee se va\u0161e sm\u011brovac\u00ed tabulka aktualizovala tak, aby kter\u00e1koliv z t\u011bchto IP adres v poolu byla sm\u011brov\u00e1na na toto za\u0159\u00edzen\u00ed, jinak nedostanete \u017e\u00e1dn\u00fd zp\u011btn\u00fd provoz. Abychom zkontrolovali spr\u00e1vnost nastaven\u00ed, zopakujeme postup pingov\u00e1n\u00ed cloudov\u00e9ho routeru, kter\u00fd jsme d\u011blali pro statick\u00fd NAT. Otev\u0159u okno routeru Router 1, abych vid\u011bl \u00falohy v re\u017eimu lad\u011bn\u00ed, a provedu ping z ka\u017ed\u00e9ho ze 3 za\u0159\u00edzen\u00ed.<\/p>\n

\"\u0160kolen\u00ed
\n
\nVid\u00edme, \u017ee v\u0161echny adresy zdroj\u016f, ze kter\u00fdch pakety pingu p\u0159ich\u00e1zej\u00ed, odpov\u00eddaj\u00ed nastaven\u00edm. P\u0159itom ping z po\u010d\u00edta\u010de PC0 nepro\u0161el, proto\u017ee mu chyb\u011bla voln\u00e1 vn\u011bj\u0161\u00ed adresa. Kdy\u017e se pod\u00edv\u00e1te do nastaven\u00ed Routeru 1, uvid\u00edte, \u017ee v sou\u010dasn\u00e9 dob\u011b jsou pou\u017e\u00edv\u00e1ny adresy poolu 200.124.22.1 a 200.124.22.2. Nyn\u00ed deaktivuji p\u0159eklad a uvid\u00edte, jak se \u0159\u00e1dky jeden po druh\u00e9m ztr\u00e1cej\u00ed. Znovu spou\u0161t\u00edm ping z po\u010d\u00edta\u010de PC0 a jak vid\u00edte, nyn\u00ed v\u0161e funguje, proto\u017ee se mu poda\u0159ilo z\u00edskat uvoln\u011bnou vn\u011bj\u0161\u00ed adresu 200.124.22.1. <\/p>\n

Jak lze vy\u010distit tabulku NAT a zru\u0161it zadanou transformaci adres? Jdeme do nastaven\u00ed routeru Router0 a zad\u00e1me p\u0159\u00edkaz clear ip nat translation * se \u201ehv\u011bzdi\u010dkou\u201c na konci \u0159\u00e1dku. Pokud nyn\u00ed pod\u00edv\u00e1me na stav transformace pomoc\u00ed p\u0159\u00edkazu show ip nat translation, syst\u00e9m n\u00e1m zobraz\u00ed pr\u00e1zdn\u00fd \u0159\u00e1dek. <\/p>\n

Pro zobrazen\u00ed statistik NAT se pou\u017e\u00edv\u00e1 p\u0159\u00edkaz show ip nat statistics. <\/p>\n

\"\u0160kolen\u00ed
\n
\nToto je velmi u\u017eite\u010dn\u00fd p\u0159\u00edkaz, kter\u00fd v\u00e1m umo\u017e\u0148uje zjistit celkov\u00fd po\u010det dynamick\u00fdch, statick\u00fdch a roz\u0161\u00ed\u0159en\u00fdch p\u0159evod\u016f NAT\/PAT. Vid\u00edte, \u017ee je rovno 0, proto\u017ee jsme p\u0159edchoz\u00edm p\u0159\u00edkazem vymazali data o p\u0159evodech. Zde se zobrazuj\u00ed vstupn\u00ed a v\u00fdstupn\u00ed rozhran\u00ed, po\u010det \u00fasp\u011b\u0161n\u00fdch a ne\u00fasp\u011b\u0161n\u00fdch p\u0159evod\u016f hits a misses (po\u010det ne\u00fasp\u011bch\u016f souvis\u00ed s nedostatkem voln\u00e9 extern\u00ed adresy pro vnit\u0159n\u00ed hostitele), n\u00e1zev p\u0159\u00edstupov\u00e9ho seznamu a poolu. <\/p>\n

Nyn\u00ed se dostaneme k nejpopul\u00e1rn\u011bj\u0161\u00ed form\u011b p\u0159evodu IP adres \u2013 roz\u0161\u00ed\u0159en\u00e9mu NAT, nebo PAT. Pro nastaven\u00ed PAT je t\u0159eba postupovat stejn\u00fdmi kroky jako p\u0159i konfiguraci dynamick\u00e9ho NAT: ur\u010dit vstupn\u00ed a v\u00fdstupn\u00ed rozhran\u00ed routeru, identifikovat \u201ezaj\u00edmav\u00fd\u201c provoz, vytvo\u0159it pool NAT a nastavit PAT. M\u016f\u017eeme vytvo\u0159it stejn\u00fd pool z n\u011bkolika adres jako v p\u0159edchoz\u00edm p\u0159\u00edpad\u011b, ale nen\u00ed to nutn\u00e9, proto\u017ee v PAT je st\u00e1le pou\u017e\u00edv\u00e1na stejn\u00e1 extern\u00ed adresa. Rozd\u00edl mezi nastaven\u00edm dynamick\u00e9ho NAT a PAT spo\u010d\u00edv\u00e1 pouze v kl\u00ed\u010dov\u00e9m slov\u011b overload, kter\u00fdm kon\u010d\u00ed posledn\u00ed nastavovac\u00ed p\u0159\u00edkaz. Po zad\u00e1n\u00ed tohoto slova se dynamick\u00fd NAT automaticky p\u0159etvo\u0159\u00ed na PAT.<\/p>\n

\"\u0160kolen\u00ed
\n
\nKrom\u011b toho pou\u017e\u00edv\u00e1te pouze jednu adresu v poolu NWKING, nap\u0159\u00edklad 200.124.22.1, ale uv\u00e1d\u00edte ji dvakr\u00e1t jako po\u010d\u00e1te\u010dn\u00ed a koncovou extern\u00ed adresu se s\u00ed\u0165ovou maskou 255.255.255.0. M\u016f\u017eete to zjednodu\u0161it tak, \u017ee m\u00edsto \u0159\u00e1dku ip nat 1 pool NWKING 200.124.22.1 200.124.22.1 netmask 255.255.255.0 pou\u017eijete parametr source interface a pevnou adresu 200.124.22.1 rozhran\u00ed G0\/1. V tomto p\u0159\u00edpad\u011b budou v\u0161echny m\u00edstn\u00ed adresy p\u0159i p\u0159\u00edstupu na internet p\u0159ev\u00e1d\u011bny na tuto IP adresu. <\/p>\n

V poolu m\u016f\u017eete tak\u00e9 pou\u017e\u00edt jakoukoli jinou IP adresu, nemus\u00ed nutn\u011b odpov\u00eddat konkr\u00e9tn\u00edmu fyzick\u00e9mu rozhran\u00ed. Mus\u00edte si v\u0161ak b\u00fdt jisti, \u017ee v\u0161echny routery v s\u00edti budou schopny sm\u011brovat odpov\u011bdn\u00ed provoz na v\u00e1mi vybran\u00e9 za\u0159\u00edzen\u00ed. Nev\u00fdhodou NAT je, \u017ee jej nelze pou\u017e\u00edt pro pr\u016fchoz\u00ed adresaci, proto\u017ee dokud se zp\u011btn\u00fd paket vr\u00e1t\u00ed k m\u00edstn\u00edmu za\u0159\u00edzen\u00ed, jeho dynamick\u00e1 NAT IP adresa se m\u016f\u017ee zm\u011bnit. To znamen\u00e1, \u017ee se mus\u00edte ujistit, \u017ee vybran\u00e1 IP adresa z\u016fstane dostupn\u00e1 po celou dobu spojen\u00ed. <\/p>\n

Pod\u00edvejme se na to prost\u0159ednictv\u00edm Packet Traceru. Nejprve mus\u00edm odstranit dynamick\u00fd NAT p\u0159\u00edkazem no Ip nat inside source list 1 NWKING a odstranit NAT pool pomoc\u00ed p\u0159\u00edkazu no Ip nat pool NWKING 200.124.22.1 200.124.22.2 netmask 225.255.255.252. <\/p>\n

Pot\u00e9 mus\u00edm vytvo\u0159it PAT pool p\u0159\u00edkazem Ip nat pool NWKING 200.124.22.2 200.124.22.2 netmask 225.255.255.255. Tentokr\u00e1t pou\u017e\u00edv\u00e1m IP adresu, kter\u00e1 nepat\u0159\u00ed fyzick\u00e9mu za\u0159\u00edzen\u00ed, proto\u017ee fyzick\u00e9 za\u0159\u00edzen\u00ed m\u00e1 adresu 200.124.22.1 a j\u00e1 chci pou\u017e\u00edt 200.124.22.2. V na\u0161em p\u0159\u00edpad\u011b to funguje, proto\u017ee m\u00e1me m\u00edstn\u00ed s\u00ed\u0165.<\/p>\n

D\u00e1le nastav\u00edm PAT p\u0159\u00edkazem Ip nat inside source list 1 pool NWKING overload. Po zad\u00e1n\u00ed tohoto p\u0159\u00edkazu se aktivuje transformace adres PAT. Abych zkontroloval spr\u00e1vnost nastaven\u00ed, p\u0159ejdu k na\u0161im za\u0159\u00edzen\u00edm, serveru a dv\u011bma po\u010d\u00edta\u010d\u016fm, a pinguji z po\u010d\u00edta\u010de PC0 Router1 na adresu 200.124.22.10. V okn\u011b nastaven\u00ed routeru jsou vid\u011bt ladic\u00ed \u0159\u00e1dky, kter\u00e9 ukazuj\u00ed, \u017ee zdrojem pingu, jak jsme o\u010dek\u00e1vali, je IP adresa 200.124.22.2. Z t\u00e9\u017ee adresy p\u0159ich\u00e1z\u00ed ping odeslan\u00fd po\u010d\u00edta\u010dem PC1 a serverem Server0. <\/p>\n

Pod\u00edvejme se, co se d\u011bje v tabulce transformac\u00ed routeru Router0. Vid\u00edte, \u017ee v\u0161echny transformace jsou \u00fasp\u011b\u0161n\u00e9, ka\u017ed\u00e9mu za\u0159\u00edzen\u00ed je p\u0159id\u011blena vlastn\u00ed port a v\u0161echny lok\u00e1ln\u00ed adresy jsou spojeny s Router1 p\u0159es IP adresu poolu 200.124.22.2. <\/p>\n

\"\u0160kolen\u00ed
\n
\nPou\u017e\u00edv\u00e1m p\u0159\u00edkaz show ip nat statistics, abych zobrazil statistiky PAT. <\/p>\n

\"\u0160kolen\u00ed
\n
\nVid\u00edme, \u017ee celkov\u00fd po\u010det transformac\u00ed, neboli p\u0159eklad\u016f adres, je 12, vid\u00edme charakteristiky poolu a dal\u0161\u00ed informace. <\/p>\n

Te\u010f ud\u011bl\u00e1m je\u0161t\u011b n\u011bco jin\u00e9ho \u2013 zad\u00e1m p\u0159\u00edkaz Ip nat inside source list 1 interface gigabit Ethernet g0\/1 overload. Pokud pot\u00e9 pinguji router z po\u010d\u00edta\u010de PC0, je vid\u011bt, \u017ee paket p\u0159i\u0161el z adresy 200.124.22.1, tedy z fyzick\u00e9ho rozhran\u00ed! To je snaz\u0161\u00ed cesta: pokud nechcete vytv\u00e1\u0159et pool, co\u017e se nej\u010dast\u011bji st\u00e1v\u00e1 p\u0159i pou\u017e\u00edv\u00e1n\u00ed dom\u00e1c\u00edch router\u016f, m\u016f\u017eete jako extern\u00ed NAT adresu pou\u017e\u00edt IP adresu fyzick\u00e9ho rozhran\u00ed routeru. Takto se nej\u010dast\u011bji prov\u00e1d\u00ed transformace adresy va\u0161eho soukrom\u00e9ho hostitele pro ve\u0159ejnou s\u00ed\u0165.
\nDnes jsme studovali velmi d\u016fle\u017eit\u00e9 t\u00e9ma, proto je nezbytn\u00e9 si v n\u011bm procvi\u010dit. Pou\u017eijte Packet Tracer, abyste ov\u011b\u0159ili sv\u00e9 teoretick\u00e9 znalosti p\u0159i \u0159e\u0161en\u00ed praktick\u00fdch \u00faloh t\u00fdkaj\u00edc\u00edch se konfigurace NAT a PAT. Skon\u010dili jsme se studiem t\u00e9matiky ICND1 \u2014 prvn\u00edho zkou\u0161ky kurzu CCNA, proto n\u00e1sleduj\u00edc\u00ed video lekci pravd\u011bpodobn\u011b v\u011bnuji shrnut\u00ed. <\/p>\n

\r\n \"P\u0159ehr\u00e1t\r\n
<\/div>\r\n <\/div><\/center>
\nD\u011bkujeme, \u017ee s n\u00e1mi z\u016fst\u00e1v\u00e1te. L\u00edb\u00ed se v\u00e1m na\u0161e \u010dl\u00e1nky? Chcete vid\u011bt v\u00edce zaj\u00edmav\u00fdch materi\u00e1l\u016f? Podpo\u0159te n\u00e1s objedn\u00e1vkou nebo doporu\u010den\u00edm zn\u00e1m\u00fdm, 30 % sleva pro u\u017eivatele Habra na jedine\u010dn\u00fd analog entry-level server\u016f, kter\u00fd jsme pro v\u00e1s vymysleli:<\/b> Ve\u0161ker\u00e1 pravda o VPS (KVM) E5-2650 v4 (6 jader) 10GB DDR4 240GB SSD 1Gbps od 20 $ nebo jak spr\u00e1vn\u011b rozd\u011blit server?<\/a><\/noindex> (k dispozici varianty s RAID1 a RAID10, a\u017e 24 jader a a\u017e 40GB DDR4).<\/p>\n

Dell R730xd za polovinu ceny?<\/b> Jen u n\u00e1s 2 x Intel TetraDeca-Core Xeon 2x E5-2697v3 2.6GHz 14C 64GB DDR4 4x960GB SSD 1Gbps 100 TB od 199 $<\/a><\/noindex> v Nizozemsku! Dell R420 \u2014 2x E5-2430 2.2GHz 6C 128GB DDR3 2x960GB SSD 1Gbps 100TB \u2014 od 99 $!<\/b><\/b> \u010ct\u011bte o tom Jak postavit infrastrukturu podnikov\u00e9 t\u0159\u00eddy s pou\u017eit\u00edm server\u016f Dell R730xd E5-2650 v4 v hodnot\u011b 9000 eur za pakatel?<\/a><\/noindex>
\n
Zdroj: habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0421\u0435\u0433\u043e\u0434\u043d\u044f \u043c\u044b \u0431\u0443\u0434\u0435\u043c \u0438\u0437\u0443\u0447\u0430\u0442\u044c PAT (Port Address Translation), \u0442\u0435\u0445\u043d\u043e\u043b\u043e\u0433\u0438\u044e \u0442\u0440\u0430\u043d\u0441\u043b\u044f\u0446\u0438\u0438 IP- \u0430\u0434\u0440\u0435\u0441\u043e\u0432 \u0441 \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435\u043c \u043f\u043e\u0440\u0442\u043e\u0432, \u0438 NAT (Network Address Translation), \u0442\u0435\u0445\u043d\u043e\u043b\u043e\u0433\u0438\u044e \u043f\u0440\u0435\u043e\u0431\u0440\u0430\u0437\u043e\u0432\u0430\u043d\u0438\u044f IP-\u0430\u0434\u0440\u0435\u0441\u043e\u0432 \u0442\u0440\u0430\u043d\u0437\u0438\u0442\u043d\u044b\u0445 \u043f\u0430\u043a\u0435\u0442\u043e\u0432. PAT \u044f\u0432\u043b\u044f\u0435\u0442\u0441\u044f \u0447\u0430\u0441\u0442\u043d\u044b\u043c \u0441\u043b\u0443\u0447\u0430\u0435\u043c NAT. \u041c\u044b \u0440\u0430\u0441\u0441\u043c\u043e\u0442\u0440\u0438\u043c \u0442\u0440\u0438 \u0442\u0435\u043c\u044b: \u2014 \u043f\u0440\u0438\u0432\u0430\u0442\u043d\u044b\u0435, \u0438\u043b\u0438 \u0432\u043d\u0443\u0442\u0440\u0435\u043d\u043d\u0438\u0435 (\u0432\u043d\u0443\u0442\u0440\u0438\u0441\u0435\u0442\u0435\u0432\u044b\u0435, \u043b\u043e\u043a\u0430\u043b\u044c\u043d\u044b\u0435) IP-\u0430\u0434\u0440\u0435\u0441\u0430 \u0438 \u043f\u0443\u0431\u043b\u0438\u0447\u043d\u044b\u0435, \u0438\u043b\u0438 \u0432\u043d\u0435\u0448\u043d\u0438\u0435 IP-\u0430\u0434\u0440\u0435\u0441\u0430; \u2014 NAT \u0438 PAT; \u2014 \u043d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0430 NAT\/ PAT. \u041d\u0430\u0447\u043d\u0435\u043c […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":28314,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-37723","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Tr\u00e9nink Cisco 200-125 CCNA v3.0. 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