{"id":660,"date":"2020-04-13T11:07:16","date_gmt":"2020-04-13T09:07:16","guid":{"rendered":"http:\/\/tech.sosthe.sk\/?page_id=660"},"modified":"2020-04-13T11:07:16","modified_gmt":"2020-04-13T09:07:16","slug":"computer-storage","status":"publish","type":"page","link":"http:\/\/tech.sosthe.sk\/index.php\/odborne-predmety\/pocitacove-systemy\/computer-storage\/","title":{"rendered":"Computer Storage"},"content":{"rendered":"

Delenie storage pod\u013ea pr\u00edstupu k d\u00e1tam<\/span><\/h3>\n

Z\u00e1kladn\u00e9 rozdelenie d\u00e1tov\u00fdch \u00falo\u017e\u00edsk je pod\u013ea sp\u00f4sobu, ak\u00fdm pristupuj\u00fa k ulo\u017een\u00fdm d\u00e1tam.\u00a0M\u00f4\u017eu z\u00edskava\u0165\u00a0 <\/span>s\u00fabory<\/span><\/strong><\/em>\u00a0(adresuj\u00fa s\u00fabory) pomocou s\u00faborovo zalo\u017een\u00fdch (file-based) protokolov ako NFS alebo SMB \/ CIFS.\u00a0Alebo pristupova\u0165 priamo k m\u00e9diu a \u010d\u00edta\u0165\u00a0<\/span>diskov\u00e9 bloky<\/span><\/strong><\/em>, ktor\u00e9 prev\u00e1dza na s\u00fabory, \u010do je be\u017en\u00e9 u lok\u00e1lne pripojen\u00fdch diskov alebo SAN siet\u00ed.<\/span><\/p>\n

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<\/h3>\n

Architekt\u00fary pripojenia storage<\/span><\/h3>\n

DAS – Directly Attached Storage<\/span><\/h4>\n

Priamo pripojen\u00e9 disky (zariadenia) k po\u010d\u00edta\u010du.\u00a0Jedn\u00e1 sa o disky, ktor\u00e9 s\u00fa pripojen\u00e9 priamo k intern\u00e9mu alebo extern\u00e9mu diskov\u00e9mu radi\u010du.\u00a0Teda bu\u010f disky v po\u010d\u00edta\u010di, alebo jednoduch\u00e9 diskov\u00e9 pole, ktor\u00e9 je pripojen\u00e9 k po\u010d\u00edta\u010du spojom Point to Point.\u00a0V praxi sa pou\u017e\u00edva rozhranie\u00a0<\/span>SCSI<\/span><\/strong><\/em>\u00a0,\u00a0<\/span>SAS<\/span><\/strong><\/em>\u00a0alebo\u00a0<\/span>SATA<\/span><\/strong><\/em>.<\/span><\/p>\n

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NAS – Network Attached Storage<\/span><\/h4>\n

D\u00e1tov\u00e9 \u00falo\u017eisko pripojen\u00e9 po sieti, vych\u00e1dza z my\u0161lienky\u00a0<\/span>s\u00faborov\u00fdch serverov<\/span><\/strong><\/em>\u00a0(file servers).\u00a0Je reprezentovan\u00e9 serverom alebo \u0161peci\u00e1lnym hardv\u00e9rom, ku ktor\u00e9mu je pripojen\u00e9 diskov\u00e9 pole (\u010dasto DAS). D\u00e1ta sa pomocou\u00a0<\/span>zdie\u013eania<\/span><\/strong><\/em>\u00a0(sharing) prip\u00e1jaj\u00fa k r\u00f4znym po\u010d\u00edta\u010dom.\u00a0\u010ci\u017ee ak na jednom PC vytvor\u00edme zdie\u013ean\u00fd adres\u00e1r, ktor\u00fd na inom po\u010d\u00edta\u010di pripoj\u00edme, vyu\u017e\u00edvame NAS v jeho jednoduchej forme. Okrem toho s\u00fa vytvoren\u00e9 \u0161peci\u00e1lne storage zariadenia (skladaj\u00fa sa z NAS syst\u00e9mu, ktor\u00e9 vytv\u00e1ra rozhranie k u\u017e\u00edvate\u013eovi, a diskov\u00e9ho po\u013ea), ktor\u00e9 funguj\u00fa na princ\u00edpe NAS a prin\u00e1\u0161aj\u00fa ve\u013ea v\u00fdhod pre v\u00e4\u010d\u0161ie prostredia.<\/span><\/p>\n

Pri zdie\u013ean\u00ed d\u00e1t do siete sa vyu\u017e\u00edva nieko\u013eko (s\u00faborovo zalo\u017een\u00fdch) protokolov.\u00a0P\u00f4vodn\u00fd bol\u00a0<\/span>Server Message Block<\/span><\/em><\/strong> (SMB) vyvinut\u00fd v IBM a pou\u017e\u00edvan\u00fd od MS Dosu a prv\u00fdch Windows. U\u017e pred dlh\u0161ou dobou upravil Microsoft tento protokol a vytvoril\u00a0<\/span>Common Internet File System<\/span><\/em><\/strong>\u00a0(CIFS), ktor\u00fd je pou\u017e\u00edvan\u00fd dnes.\u00a0Na druhej strane ved\u013ea SMB vytvoril Sun protokol\u00a0<\/span>Network File System<\/span><\/em><\/strong>\u00a0(NFS), ktor\u00fd je dnes pou\u017e\u00edvan\u00fd v prostred\u00ed Linuxu a \u010fal\u0161\u00edch OS.\u00a0\u010eal\u0161ie mo\u017en\u00e9 protokoly s\u00fa FTP, HTTP a pod.<\/span><\/p>\n

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SAN – Storage Area Network<\/span><\/h4>\n

Najv\u00fdkonnej\u0161ie rie\u0161enie vzdialen\u00e9ho pripojenia storage. Vyu\u017e\u00edva samostatn\u00e9 dedikovan\u00e9 siete pre storage komunik\u00e1ciu.\u00a0Pou\u017e\u00edvaj\u00fa sa protokoly, ktor\u00e9 pracuj\u00fa priamo s diskov\u00fdmi blokmi.\u00a0Z\u00e1kladom je\u00a0<\/span>SCSI protokol<\/span><\/strong><\/em> (nemysl\u00edme t\u00fdm SCSI rozhranie), ktor\u00fd je zabalen\u00fd pre prenos cez <\/span>Fibre Channel<\/span><\/strong><\/em>\u00a0(FC) pomocou\u00a0<\/span>Fibre Channel Protocol<\/span><\/strong> (FCP), alebo pre prenos cez\u00a0<\/span>TCP\/IP<\/span><\/strong><\/em>\u00a0pomocou\u00a0<\/span>Internet Small Computer System Protocol (iSCSI)<\/span><\/strong>.\u00a0Pr\u00edpadne niektor\u00e9 \u010fal\u0161ie protokoly, ktor\u00e9 nie s\u00fa teraz pr\u00edli\u0161 roz\u0161\u00edren\u00e9 ako Fibre Channel over Ethernet (FCoE), SCSI over Ethernet alebo \u010fal\u0161ie.\u00a0Z vy\u0161\u0161ie uveden\u00e9ho vypl\u00fdva, \u017ee disk (zariadenie) pripojen\u00fd cez SAN v syst\u00e9me vyzer\u00e1, ako by bol k po\u010d\u00edta\u010du priamo pripojen\u00fd.<\/span><\/p>\n

SAN diskov\u00e9 pole<\/span><\/strong><\/em> sa sklad\u00e1 z kontrol\u00e9ru a diskov\u00fdch pol\u00ed. Na kontrol\u00e9ri sa vytv\u00e1raj\u00fa ur\u010dit\u00e9 diskov\u00e9 priestory –<\/span>\u00a0virtu\u00e1lne disky<\/span><\/strong><\/em>\u00a0(identifikuj\u00fa sa pomocou LUN –<\/span>\u00a0LUN<\/span><\/strong> ), ktor\u00e9 sa priradia ur\u010dit\u00fdm serverom. Ak chceme rovnak\u00fd LUN zdie\u013ea\u0165 pomocou viac serverov, tak sa mus\u00ed o\u0161etri\u0165 nejakou \u0161peci\u00e1lnou met\u00f3dou, inak doch\u00e1dza ku kol\u00edzi\u00e1m (po\u0161kodeniu d\u00e1t).<\/span><\/p>\n

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SAN cez Fibre Channel (FC)<\/span><\/strong><\/p>\n

P\u00f4vodne jedin\u00fd typ SAN siete.\u00a0Vyu\u017e\u00edvaj\u00fa sa optick\u00e9 vedenia <\/span>Fibre Optics<\/span><\/strong><\/em>\u00a0(v s\u00fa\u010dasnosti o r\u00fdchlosti 4Gbps) a protokolu\u00a0<\/span>FCP<\/span><\/strong><\/em>.\u00a0S\u00fa potrebn\u00e9 \u0161peci\u00e1lne FC switche (ak nem\u00e1me iba spojenie Point-to-Point) a servery musia ma\u0165 <\/span>Fibre Channel Host Bus Adapter<\/span><\/strong><\/em>\u00a0(HBA), ktor\u00fd nahr\u00e1dza SCSI radi\u010d.\u00a0Ka\u017ed\u00fd HBA m\u00e1 svoju unik\u00e1tnu adresu\u00a0<\/span>World Wide Name – WWN<\/span><\/strong><\/em>\u00a0(obdoba MAC adresy u sie\u0165ovej karty), HBA m\u00f4\u017ee ma\u0165 jeden alebo viac portov, ka\u017ed\u00fd port m\u00e1 svoju\u00a0<\/span>port WWN<\/span><\/strong><\/em>\u00a0(WWNP) adresu a cel\u00fd HBA m\u00e1\u00a0<\/span>node WWN<\/span><\/em><\/strong>\u00a0(WWNN) adresu.\u00a0HBA zais\u0165uje komunik\u00e1ciu po sieti a zap\u00fazdruje SCSI do FCP (a opa\u010dne).<\/span><\/p>\n

SAN cez TCP\/IP – iSCSI<\/span><\/strong><\/p>\n

SAN cez FC je zna\u010dne drah\u00e1 z\u00e1le\u017eitos\u0165, tak\u017ee sa v \u010dase, ke\u010f sa za\u010dal pou\u017e\u00edva\u0165\u00a0<\/span>gigabitov\u00fd ethernet<\/span><\/strong><\/em>\u00a0(v tej dobe sa pou\u017e\u00edvalo FC s r\u00fdchlos\u0165ou 2Gbps) objavil \u0161tandardizovan\u00fd protokol\u00a0<\/span>Internet Small Computer System Protocol<\/span><\/strong>\u00a0(iSCSI).\u00a0Ten zapuzdruje SCSI do TCP\/IP protokolu, tak\u017ee m\u00f4\u017ee fungova\u0165 na be\u017enej ethernetovej sieti (podmienkou je minim\u00e1lna r\u00fdchlos\u0165 1 Gbps). Teoreticky m\u00f4\u017ee fungova\u0165 na u\u017e existuj\u00facej sieti (switchoch a sie\u0165ov\u00fdch kart\u00e1ch), ale v praxi sa rozhodne odpor\u00fa\u010da vybudova\u0165 oddelen\u00fa sie\u0165 pre SAN (pre d\u00e1tov\u00fa prev\u00e1dzku nie je probl\u00e9m vy\u0165a\u017ei\u0165 1Gbps sie\u0165).<\/span><\/p>\n

TCP protokol<\/span><\/strong><\/em> s\u00edce nie je pre d\u00e1tov\u00fd prenos tak dobr\u00fd ako<\/span> FCP protokol<\/span><\/strong><\/em>, ktor\u00fd bol \u0161peci\u00e1lne pre tento \u00fa\u010del vyvinut\u00fd, ale je dostato\u010dn\u00fd.\u00a0V dne\u0161nej dobe s\u00fa SAN siete zalo\u017een\u00e9 na iSCSI zna\u010dne roz\u0161\u00edren\u00e9. Je tu v\u0161ak ot\u00e1zka sie\u0165ovej karty.\u00a0iSCSI sa m\u00f4\u017ee prev\u00e1dzkova\u0165 cez klasick\u00fa sie\u0165ov\u00fa kartu, ale potom v\u0161etko spracovanie (zap\u00fazdrovanie SCSI do iSCSI) vykon\u00e1va procesor po\u010d\u00edta\u010da. Druh\u00e1 mo\u017enos\u0165 je zak\u00fapi\u0165 \u0161peci\u00e1lny<\/span> iSCSI HBA<\/span><\/strong><\/em>, ktor\u00fd vykon\u00e1va tieto \u00fakony a po\u010d\u00edta\u010di u\u017e odovzd\u00e1va norm\u00e1lne SCSI.<\/span><\/p>\n

 <\/p>\n

Diskov\u00e9 rozhrania<\/span><\/h3>\n

PATA – Parallel Advance Technology Attachment<\/span><\/h4>\n

\u0160tandardn\u00e9 rozhranie pre pripojenie zariadenia pre ukladanie d\u00e1t (ako pevn\u00e9 disky a CD-ROM mechaniky) vn\u00fatri po\u010d\u00edta\u010da.\u00a0Vyu\u017e\u00edva paraleln\u00fa komunik\u00e1ciu. Predt\u00fdm bolo ozna\u010dovan\u00e9 len ako ATA.\u00a0Existuj\u00fa (skoro) synonym\u00e1 ako IDE (Integrated Drive Electronics), EIDE (Enhanced IDE) a ATAPI (AT Attachment Packet Interface).<\/span><\/p>\n

SATA – Serial ATA<\/span><\/h4>\n

Zbernicov\u00e1 technol\u00f3gia pre po\u010d\u00edta\u010de, ktor\u00e1 je prim\u00e1rne ur\u010den\u00e1 pre prenos d\u00e1t na a z pevn\u00fdch diskov a optick\u00fdch mechan\u00edk. Modernej\u0161ia s\u00e9riov\u00e1 verzia klasick\u00e9ho ATA. SATA 2 m\u00e1 teoreticky 3Gb\/s = 375 MBps.<\/span><\/p>\n

SCSI – Small Computer Systems Interface<\/span><\/h4>\n

Ide o skupinu \u0161tandardov pre fyzick\u00e9 pripojenie a prenos d\u00e1t medzi po\u010d\u00edta\u010dom a perif\u00e9rnymi zariadeniami. Pou\u017e\u00edva paraleln\u00fd zbernicov\u00fd port.\u00a0Ultra640 SCSI teoreticky 640 MBps.<\/span><\/p>\n

SAS – Serial Attached SCSI<\/span><\/h4>\n

SAS vzniklo, rovnako ako SATA, ako modern\u00e9 roz\u0161\u00edrenie zbernicovej technol\u00f3gie pre pripojenie pevn\u00fdch diskov a optick\u00fdch mechan\u00edk. Jedn\u00e1 sa o s\u00e9riov\u00fa zbernicu vych\u00e1dzaj\u00facu z SCSI, ktor\u00e1 je sp\u00e4tne kompatibiln\u00e1 so SATA diskami. Teoreticky 3Gbps.\u00a0Intern\u00e9 disky bu\u010f SATA 2 alebo SCSI.<\/span><\/p>\n

Fiber Channel – FC<\/span><\/h4>\n

Jedn\u00e1 sa o sie\u0165ov\u00fa technol\u00f3giu prim\u00e1rne ur\u010den\u00fa pre d\u00e1tov\u00e9 siete (storage networking), stalo sa \u0161tandardom pre SAN \u00falo\u017eiska.\u00a0Tradi\u010dne pou\u017e\u00edva optick\u00e9 k\u00e1ble, ktor\u00e9 m\u00f4\u017eu dosahova\u0165 r\u00fdchlos\u0165 a\u017e 20 Gbps. Pou\u017e\u00edva sa pre vedenie medzi servermi a SAN kontrol\u00e9rmi, ale aj ako rozhranie na diskoch vn\u00fatri SAN diskov\u00fdch pol\u00ed.<\/span><\/p>\n

FATA<\/span><\/h4>\n

Lacnej\u0161\u00ed variant, kedy sa be\u017en\u00fd SATA disk vybav\u00ed FC konektorom, tak\u017ee sa d\u00e1 pripoji\u0165 do Enterprise diskov\u00fdch pol\u00ed.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

Delenie storage pod\u013ea pr\u00edstupu k d\u00e1tam Z\u00e1kladn\u00e9 rozdelenie d\u00e1tov\u00fdch \u00falo\u017e\u00edsk je pod\u013ea sp\u00f4sobu, ak\u00fdm pristupuj\u00fa k ulo\u017een\u00fdm d\u00e1tam.\u00a0M\u00f4\u017eu z\u00edskava\u0165\u00a0 s\u00fabory\u00a0(adresuj\u00fa s\u00fabory) pomocou s\u00faborovo zalo\u017een\u00fdch (file-based)…<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":13,"menu_order":1,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"_links":{"self":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/pages\/660"}],"collection":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/comments?post=660"}],"version-history":[{"count":1,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/pages\/660\/revisions"}],"predecessor-version":[{"id":665,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/pages\/660\/revisions\/665"}],"up":[{"embeddable":true,"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/pages\/13"}],"wp:attachment":[{"href":"http:\/\/tech.sosthe.sk\/index.php\/wp-json\/wp\/v2\/media?parent=660"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}