{"id":32952,"date":"2019-10-31T21:49:55","date_gmt":"2019-10-31T18:49:55","guid":{"rendered":"https:\/\/prohoster.info\/blog\/kak-zavisit-perevod-termina-trunk-ot-vendora-kommutatorov\/"},"modified":"2019-10-31T21:49:55","modified_gmt":"2019-10-31T18:49:55","slug":"kak-zavisit-perevod-termina-trunk-ot-vendora-kommutatorov","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/kak-zavisit-perevod-termina-trunk-ot-vendora-kommutatorov","title":{"rendered":"Jak se p\u0159eklad term\u00ednu trunk li\u0161\u00ed podle dodavatele p\u0159ep\u00edna\u010d\u016f?","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Na tuto chybu (nebo, chcete-li, nesrovnalost) jsem upozornil p\u0159i kontrole p\u0159ekladu u p\u0159ep\u00edna\u010d\u016f NETGEAR. Je to proto, \u017ee p\u0159i p\u0159ekladu term\u00ednu \u201ctrunk\u201d<\/strong> je nutn\u00e9 nutn\u011b zohlednit, jak\u00fd v\u00fdklad dodavatel zast\u00e1v\u00e1 \u2014 Cisco<\/strong> nebo HP<\/strong>, nebo\u0165 mezi nimi je velmi rozd\u00edln\u00fd technick\u00fd v\u00fdznam.
\nPoj\u010fme se na to pod\u00edvat.<\/p>\n

Pod\u00edv\u00e1me se na probl\u00e9m na n\u00e1sleduj\u00edc\u00edch p\u0159\u00edkladech:<\/p>\n

<\/p>\n

1. Cisco<\/strong><\/p>\n

<\/p>\n

\"Jak<\/p>\n

<\/p>\n

2. HP<\/strong><\/p>\n

<\/p>\n

\"Jak<\/p>\n

<\/p>\n

Pozorn\u00fd \u010dten\u00e1\u0159 si v\u0161imne, \u017ee \u201ctrunk\u201d<\/strong> v t\u011bchto p\u0159\u00edkladech m\u00e1 r\u016fzn\u00fd v\u00fdznam.<\/p>\n

<\/p>\n

Budeme \u201ekopat\u201c.<\/p>\n

<\/a><\/noindex><\/p>\n

Verze Cisco<\/h2>\n

<\/p>\n

\"Jak<\/p>\n

<\/p>\n

Cisco<\/strong> pod \u201ctrunk<\/strong>\u2019em\u201d rozum\u00ed kan\u00e1l typu \u201cpoint-to-point\u201d<\/em> (komunika\u010dn\u00ed kan\u00e1l, p\u0159\u00edmo spojuj\u00edc\u00ed dv\u011b za\u0159\u00edzen\u00ed)<\/em>, kter\u00fd spojuje p\u0159ep\u00edna\u010d a dal\u0161\u00ed s\u00ed\u0165ov\u00e9 za\u0159\u00edzen\u00ed, nap\u0159\u00edklad dal\u0161\u00ed p\u0159ep\u00edna\u010d nebo router. Jeho \u00fakolem je p\u0159en\u00e1\u0161et provoz n\u011bkolika VLAN p\u0159es jeden kan\u00e1l a zaji\u0161\u0165ovat jim p\u0159\u00edstup k cel\u00e9 s\u00edti<\/em>. V lidov\u00e9m jazyce se naz\u00fdv\u00e1 \u201etrunkem\u201d<\/strong>, co\u017e je logick\u00e9. <\/p>\n

<\/p>\n

Princip \u010dinnosti<\/h3>\n

<\/p>\n

Za\u010dneme s ot\u00e1zkou, co je to VLAN?<\/strong><\/h4>\n

<\/p>\n

VLAN<\/strong> roz\u0161i\u0159uje se jako Virtual local area network<\/em> nebo virtu\u00e1ln\u00ed lok\u00e1ln\u00ed s\u00ed\u0165. Je to technologie, kter\u00e1 umo\u017e\u0148uje rozd\u011blit jednu fyzickou s\u00ed\u0165 na n\u011bkolik logick\u00fdch, kter\u00e9 funguj\u00ed nez\u00e1visle na sob\u011b. Nap\u0159\u00edklad, v podniku existuj\u00ed person\u00e1ln\u00ed odd\u011blen\u00ed<\/strong>, \u00fa\u010detn\u00ed odd\u011blen\u00ed<\/strong> a IT odd\u011blen\u00ed<\/strong>. Maj\u00ed sv\u00e9 vlastn\u00ed p\u0159ep\u00edna\u010de, kter\u00e9 jsou propojeny p\u0159es centr\u00e1ln\u00ed p\u0159ep\u00edna\u010d do jedn\u00e9 s\u00edt\u011b, a pr\u00e1v\u011b tyto s\u00edt\u011b t\u011bchto odd\u011blen\u00ed je pot\u0159eba odd\u011blit. Tehdy p\u0159ich\u00e1z\u00ed na pomoc technologie VLAN. <\/p>\n

<\/p>\n

\"Jak<\/p>\n

<\/p>\n

Takto vypad\u00e1 s\u00ed\u0165 rozd\u011blen\u00e1 na VLANy (virtu\u00e1ln\u00ed s\u00edt\u011b).<\/em><\/p>\n

<\/p>\n

\u010casto se pro ozna\u010den\u00ed VLAN pou\u017e\u00edvaj\u00ed r\u016fzn\u00e9 barvy. <\/p>\n

<\/p>\n

\"Jak<\/p>\n

<\/p>\n

Nap\u0159\u00edklad porty ozna\u010den\u00e9 zelenou barvou pat\u0159\u00ed do jednoho VLAN, zat\u00edmco porty ozna\u010den\u00e9 \u010dervenou barvou pat\u0159\u00ed do jin\u00e9ho. T\u00edm p\u00e1dem po\u010d\u00edta\u010de, kter\u00e9 jsou v jednom VLAN, mohou komunikovat pouze mezi sebou<\/strong>, zat\u00edmco s po\u010d\u00edta\u010di, kter\u00e9 pat\u0159\u00ed do jin\u00e9ho VLAN, nemohou. <\/p>\n

<\/p>\n

Zm\u011bny v tabulce p\u0159ep\u00edn\u00e1n\u00ed v VLAN<\/strong><\/h4>\n

<\/p>\n

P\u0159i vytv\u00e1\u0159en\u00ed VLAN se do tabulky p\u0159ep\u00edn\u00e1n\u00ed u p\u0159ep\u00edna\u010d\u016f p\u0159id\u00e1v\u00e1 dal\u0161\u00ed pole, ve kter\u00e9m jsou uvedeny identifik\u00e1tory VLAN. Zjednodu\u0161en\u011b to vypad\u00e1 takto: <\/p>\n

<\/p>\n

\"Jak<\/p>\n

<\/p>\n

Zde vid\u00edme, \u017ee porty 1 a 2 pat\u0159\u00ed VLANu 2, zat\u00edmco porty 3 a 4 pat\u0159\u00ed VLANu 10.<\/em><\/p>\n

<\/p>\n

Jdeme d\u00e1l. Na linkov\u00e9 \u00farovni se data p\u0159en\u00e1\u0161ej\u00ed ve form\u011b r\u00e1mc\u016f (framed<\/em>). P\u0159i p\u0159enosu r\u00e1mc\u016f z jednoho switche na druh\u00fd je pot\u0159eba informace o tom, ke kter\u00e9mu VLAN pat\u0159\u00ed ten kter\u00fd r\u00e1mec. Tato informace se p\u0159id\u00e1v\u00e1 do p\u0159en\u00e1\u0161en\u00e9ho r\u00e1mce. V sou\u010dasnosti se k tomuto \u00fa\u010delu pou\u017e\u00edv\u00e1 otev\u0159en\u00fd standard IEEE 802.1Q<\/strong>. Krok za krokem evoluce r\u00e1mce ve VLAN<\/strong><\/p>\n

<\/p>\n

    \n
  1. Po\u010d\u00edta\u010d generuje a odes\u00edl\u00e1 b\u011b\u017en\u00fd r\u00e1mec (r\u00e1mec, tak\u00e9 zn\u00e1m\u00fd jako paket linkov\u00e9 \u00farovn\u011b, tj. \u00farovn\u011b switch\u016f)<\/em>, ani\u017e by cokoliv p\u0159id\u00e1val. Tento r\u00e1mec vypad\u00e1 takto:<\/li>\n<\/ol>\n

    <\/p>\n

    \"Jak<\/p>\n

    <\/p>\n

      \n
    1. Switch p\u0159ij\u00edm\u00e1 r\u00e1mec. Podle tabulky p\u0159ep\u00edn\u00e1n\u00ed rozum\u00ed, z jak\u00e9ho po\u010d\u00edta\u010de r\u00e1mec p\u0159i\u0161el, a ke kter\u00e9mu VLAN tento po\u010d\u00edta\u010d pat\u0159\u00ed. Pot\u00e9 switch s\u00e1m p\u0159id\u00e1v\u00e1 do r\u00e1mce provozn\u00ed informace, takzvan\u00fd tag.<\/em> Tag \u2013 to je pole za MAC adresou odes\u00edlatele, ve kter\u00e9m se nach\u00e1z\u00ed, zjednodu\u0161en\u011b \u0159e\u010deno, \u010d\u00edslo VLAN. Tak vypad\u00e1 r\u00e1mec s tagem:<\/li>\n<\/ol>\n

      <\/p>\n

      \"Jak<\/p>\n

      <\/p>\n

      Pot\u00e9 switch odes\u00edl\u00e1 tento r\u00e1mec na jin\u00fd switch. <\/p>\n

      <\/p>\n

        \n
      1. \n

        Switch, kter\u00fd r\u00e1mec p\u0159ij\u00edm\u00e1, extrahuje z n\u011bj informace o VLAN, tedy ch\u00e1pe, na kter\u00fd po\u010d\u00edta\u010d m\u00e1 tento r\u00e1mec odeslat, odstra\u0148uje v\u0161echny provozn\u00ed informace z r\u00e1mce a p\u0159ed\u00e1v\u00e1 ho na po\u010d\u00edta\u010d p\u0159\u00edjemce.<\/p>\n

        \n<\/li>\n

      2. \n

        Na po\u010d\u00edta\u010d p\u0159\u00edjemce p\u0159ich\u00e1z\u00ed r\u00e1mec ji\u017e bez provozn\u00edch informac\u00ed.<\/p>\n

        \n<\/li>\n<\/ol>\n

        <\/p>\n

        Nyn\u00ed se vrac\u00edme k na\u0161emu \u201ctrunk<\/strong>\u2019u\u201d. Porty switche, kter\u00e9 podporuj\u00ed VLAN, lze rozd\u011blit do dvou skupin:<\/p>\n

        <\/p>\n

          \n
        1. Tagovan\u00e9 porty (nebo trunk-porty<\/em> u Cisco<\/strong>)<\/li>\n
        2. Netagovan\u00e9 porty (nebo access porty<\/em>)<\/li>\n<\/ol>\n

          <\/p>\n

          Zaj\u00edm\u00e1me se o tagovan\u00e9 porty nebo trunk-porty. Ty slou\u017e\u00ed k tomu, aby p\u0159es jeden port<\/strong> bylo mo\u017en\u00e9 p\u0159en\u00e1\u0161et data, kter\u00e1 pat\u0159\u00ed k r\u016fzn\u00fdm VLAN<\/strong> a p\u0159ij\u00edmat data n\u011bkolika VLAN na jeden port (pamatujeme si, \u017ee obvykle porty z r\u016fzn\u00fdch VLAN se vz\u00e1jemn\u011b nevid\u00ed)<\/em>. <\/p>\n

          <\/p>\n

          \"Jak<\/p>\n

          <\/p>\n

          Na tomto obr\u00e1zku jsou tagovan\u00e9 porty \u010d\u00edslo 21<\/strong> a 22<\/strong>, kter\u00e9 spojuj\u00ed dva switche. Skrze n\u011b budou proch\u00e1zet r\u00e1mce, nap\u0159\u00edklad, od po\u010d\u00edta\u010de E<\/strong> k po\u010d\u00edta\u010di A<\/strong>, kter\u00e9 se nach\u00e1zej\u00ed ve stejn\u00e9 VLAN, podle sch\u00e9matu, kter\u00e9 je pops\u00e1no v\u00fd\u0161e. <\/p>\n

          <\/p>\n

          Spojen\u00ed mezi t\u011bmito porty je Cisco<\/strong> pr\u00e1v\u011b ozna\u010dov\u00e1no jako \u201ctrunk<\/strong>\u2019om\u201d. <\/p>\n

          <\/p>\n

          Verze HP<\/strong><\/h2>\n

          <\/p>\n

          Jak tento term\u00edn interpretuje spole\u010dnost?<\/strong> <\/p>\n

          <\/p>\n

          \"Jak<\/p>\n

          <\/p>\n

          Zde v\u016fbec nejde o VLAN. V p\u0159\u00edpad\u011b HP<\/strong> mluv\u00edme o technologii agregace kan\u00e1l\u016f. Maj\u00ed \u201ctrunk\u201d<\/strong> \u2013 je logick\u00fd kan\u00e1l<\/em>, kter\u00fd spojuje n\u011bkolik fyzick\u00fdch kan\u00e1l\u016f. n\u011bkolik fyzick\u00fdch kan\u00e1l\u016f<\/em>. Takov\u00e1 agregace umo\u017e\u0148uje zv\u00fd\u0161it propustnost a spolehlivost kan\u00e1lu. Poj\u010fme to vysv\u011btlit na p\u0159\u00edkladu. P\u0159edstavme si, \u017ee m\u00e1me dva switche, z nich\u017e ka\u017ed\u00fd m\u00e1 \u010dty\u0159i porty a tyto porty jsou propojeny \u010dty\u0159mi kabely. <\/p>\n

          <\/p>\n

          \"Jak<\/p>\n

          <\/p>\n

          Pokud nech\u00e1me v\u0161echno tak, jak je - tedy pouze propojen\u00ed mezi switchem - budou tyto spojen\u00ed p\u0159en\u00e1\u0161et r\u00e1mce navz\u00e1jem do kruhu, tj. vytvo\u0159\u00ed smy\u010dky<\/em> (p\u0159i\u010dem\u017e broadcastov\u00e9 r\u00e1mce se budou st\u00e1le znovu a znovu duplikovat, co\u017e zavede switche do broadcastov\u00e9 bou\u0159e)<\/em>. <\/p>\n

          <\/p>\n

          Takov\u00e1 duplicitn\u00ed spojen\u00ed jsou pova\u017eov\u00e1na za nadbyte\u010dn\u00e1<\/em>, a je t\u0159eba je odstranit, k tomu slou\u017e\u00ed protokol STP (Spanning Tree Protocol). Pot\u00e9 z na\u0161ich \u010dty\u0159 spojen\u00ed STP deaktivuje t\u0159i, proto\u017ee je pova\u017euje za nadbyte\u010dn\u00e1, a z\u016fstane pouze jedno spojen\u00ed. <\/p>\n

          <\/p>\n

          Pokud tedy spoj\u00edme tyto \u010dty\u0159i fyzick\u00e9 kan\u00e1ly, mezi switchemi bude jeden logick\u00fd kan\u00e1l se zv\u00fd\u0161enou propustnost\u00ed (maxim\u00e1ln\u00ed rychlost p\u0159enosu informac\u00ed p\u0159es komunika\u010dn\u00ed kan\u00e1l za jednotku \u010dasu<\/em>). Tedy budou vyu\u017eity \u010dty\u0159i kan\u00e1ly, a probl\u00e9m s nadbyte\u010dn\u00fdmi spojen\u00edmi je vy\u0159e\u0161en. Tento logick\u00fd (agregovan\u00fd) kan\u00e1l se naz\u00fdv\u00e1 HP<\/strong> \u201ctrunk<\/strong>\u2019om\u201d. <\/p>\n

          <\/p>\n

          \"Jak<\/p>\n

          <\/p>\n

          Agregaci kan\u00e1l\u016f lze nastavit mezi dv\u011bma switchemi, p\u0159ep\u00edna\u010dem a routerem. Do jednoho logick\u00e9ho kan\u00e1lu lze slou\u010dit a\u017e osm fyzick\u00fdch. Je d\u016fle\u017eit\u00e9, aby v\u0161echny porty, kter\u00e9 jsou slou\u010deny do agregovan\u00e9ho kan\u00e1lu, m\u011bly stejn\u00e9 parametry:<\/p>\n

          <\/p>\n