{"id":87364,"date":"2020-07-07T13:42:29","date_gmt":"2020-07-07T11:42:29","guid":{"rendered":"https:\/\/prohoster.info\/blog\/administrirovanie\/nastraivaem-drbd-dlya-replikaczii-hranilishha-na-dva-centos-7-servera"},"modified":"2020-07-07T13:42:29","modified_gmt":"2020-07-07T11:42:29","slug":"nastraivaem-drbd-dlya-replikaczii-hranilishha-na-dva-centos-7-servera","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/nastraivaem-drbd-dlya-replikaczii-hranilishha-na-dva-centos-7-servera","title":{"rendered":"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<p><b><i>P\u0159eklad \u010dl\u00e1nku byl vyhotoven p\u0159ed za\u010d\u00e1tkem kurzu <noindex><a rel=\"nofollow\" href=\"https:\/\/otus.pw\/17x7\/\">\u00abAdministr\u00e1tor Linux. Virtualizace a clustering\u00bb<\/a><\/noindex>.<\/i><\/b><\/p>\n<p>\nDRBD (Distributed Replicated Block Device \u2014 distribuovan\u00e9 replikovan\u00e9 blokov\u00e9 za\u0159\u00edzen\u00ed) p\u0159edstavuje distribuovan\u00e9, flexibiln\u00ed a univerz\u00e1ln\u00ed \u0159e\u0161en\u00ed pro ukl\u00e1d\u00e1n\u00ed dat pro Linux. Odr\u00e1\u017e\u00ed obsah blokov\u00fdch za\u0159\u00edzen\u00ed, jako jsou pevn\u00e9 disky, odd\u00edly, logick\u00e9 svazky atd. mezi servery. Vytv\u00e1\u0159\u00ed kopie dat na dvou \u00falo\u017en\u00fdch za\u0159\u00edzen\u00edch, aby bylo mo\u017en\u00e9 v p\u0159\u00edpad\u011b selh\u00e1n\u00ed jednoho z nich pou\u017e\u00edt data na druh\u00e9m.<\/p>\n<p>M\u016f\u017eeme \u0159\u00edci, \u017ee je to n\u011bco jako <noindex><a rel=\"nofollow\" href=\"https:\/\/www.tecmint.com\/create-raid1-in-linux\/\">s\u00ed\u0165ov\u00e1 konfigurace RAID<\/a><\/noindex> 1 s disky, kter\u00e9 jsou replikov\u00e1ny na r\u016fzn\u00e9 servery. Nicm\u00e9n\u011b to nefunguje v\u016fbec jako RAID (ani s\u00ed\u0165ov\u00fd).<noindex><a rel=\"nofollow\" name=\"habracut\"><\/a><\/noindex><\/p>\n<p>P\u016fvodn\u011b byl DRBD pou\u017e\u00edv\u00e1n p\u0159edev\u0161\u00edm v po\u010d\u00edta\u010dov\u00fdch clusterech s vysokou dostupnost\u00ed (HA \u2014 high availability), av\u0161ak od dev\u00e1t\u00e9 verze jej lze pou\u017e\u00edt tak\u00e9 k nasazen\u00ed cloudov\u00e9ho \u00falo\u017ei\u0161t\u011b.<\/p>\n<p>V tomto \u010dl\u00e1nku si uk\u00e1\u017eeme, jak nainstalovat DRBD v CentOS a stru\u010dn\u011b demonstrujeme, jak jej pou\u017e\u00edvat pro replikaci \u00falo\u017ei\u0161t\u011b (odd\u00edlu) na dvou serverech. Toto je ide\u00e1ln\u00ed \u010dl\u00e1nek pro za\u010d\u00e1tek pr\u00e1ce s DRBD v Linuxu.<\/p>\n<h3>Testovac\u00ed prost\u0159ed\u00ed<\/h3>\n<p>\nBudeme pou\u017e\u00edvat cluster ze dvou uzl\u016f pro tuto konfiguraci.<\/p>\n<ul>\n<li>Uzel 1: 192.168.56.101 \u2013 tecmint.tecmint.lan<\/li>\n<li>Uzel 2: 192.168.56.102 \u2013 server1.tecmint.lan<\/li>\n<\/ul>\n<p><\/p>\n<h4>Krok 1: Instalace bal\u00ed\u010dk\u016f DRBD<\/h4>\n<p>\nDRBD je implementov\u00e1n jako modul j\u00e1dra Linuxu. P\u0159edstavuje ovlada\u010d pro virtu\u00e1ln\u00ed blokov\u00e9 za\u0159\u00edzen\u00ed, tak\u017ee se nach\u00e1z\u00ed na sam\u00e9m dn\u011b z\u00e1sobn\u00edku vstupu a v\u00fdstupu syst\u00e9mu.<\/p>\n<p>DRBD m\u016f\u017ee b\u00fdt nainstalov\u00e1n z ELRepo nebo EPEL. Za\u010dn\u011bme importem podpisov\u00e9ho kl\u00ed\u010de bal\u00ed\u010dku ELRepo a p\u0159ipojen\u00edm repozit\u00e1\u0159e na obou uzlech, jak je uvedeno n\u00ed\u017ee.<\/p>\n<pre><code class=\"bash\"># rpm --import https:\/\/www.elrepo.org\/RPM-GPG-KEY-elrepo.org\n# rpm -Uvh http:\/\/www.elrepo.org\/elrepo-release-7.0-3.el7.elrepo.noarch.rpm<\/code><\/pre>\n<p>Pot\u00e9 je t\u0159eba nainstalovat modul j\u00e1dra DRBD a n\u00e1stroje na obou uzlech pomoc\u00ed:<\/p>\n<pre><code class=\"bash\"># yum install -y kmod-drbd84 drbd84-utils<\/code><\/pre>\n<p>\nPokud m\u00e1te zapnut\u00fd SELinux, mus\u00edte nastavit politiky tak, aby uvolnily procesy DRBD z kontroly SELinux.<\/p>\n<pre><code class=\"bash\"># semanage permissive -a drbd_t\n<\/code><\/pre>\n<p>\nKrom\u011b toho, pokud ve va\u0161em syst\u00e9mu b\u011b\u017e\u00ed firewall (firewalld), mus\u00edte p\u0159idat port DRBD 7789, aby bylo povoleno synchronizaci dat mezi dv\u011bma uzly.<\/p>\n<p>Spus\u0165te tyto p\u0159\u00edkazy pro prvn\u00ed uzel:<\/p>\n<pre><code class=\"bash\"># firewall-cmd --permanent --add-rich-rule='rule family=&quot;ipv4&quot;  source address=&quot;192.168.56.102&quot; port port=&quot;7789&quot; protocol=&quot;tcp&quot; accept'\n# firewall-cmd --reload<\/code><\/pre>\n<p>\nPot\u00e9 spus\u0165te tyto p\u0159\u00edkazy pro druh\u00fd uzel:<\/p>\n<pre><code class=\"bash\"># firewall-cmd --permanent --add-rich-rule='rule family=&quot;ipv4&quot; source address=&quot;192.168.56.101&quot; port port=&quot;7789&quot; protocol=&quot;tcp&quot; accept'\n# firewall-cmd --reload<\/code><\/pre>\n<p><\/p>\n<h4>Krok 2. P\u0159\u00edprava n\u00edzko\u00farov\u0148ov\u00e9ho \u00falo\u017ei\u0161t\u011b<\/h4>\n<p>\nNyn\u00ed, kdy\u017e m\u00e1me nainstalov\u00e1no DRBD na obou uzlech clustera, mus\u00edme na nich p\u0159ipravit \u00falo\u017ei\u0161t\u011b p\u0159ibli\u017en\u011b stejn\u00e9 velikosti. M\u016f\u017ee to b\u00fdt odd\u00edl pevn\u00e9ho disku (nebo cel\u00fd fyzick\u00fd pevn\u00fd disk), softwarov\u00e9 za\u0159\u00edzen\u00ed RAID, <noindex><a rel=\"nofollow\" href=\"https:\/\/www.tecmint.com\/create-lvm-storage-in-linux\/\">logick\u00fd svazek LVM<\/a><\/noindex> nebo jak\u00fdkoliv jin\u00fd typ blokov\u00e9ho za\u0159\u00edzen\u00ed, kter\u00e9 m\u00e1te ve sv\u00e9m syst\u00e9mu.<\/p>\n<p>Pro tento \u010dl\u00e1nek vytvo\u0159\u00edme testovac\u00ed blokov\u00e9 za\u0159\u00edzen\u00ed o velikosti 2 GB pomoc\u00ed p\u0159\u00edkazu dd.<\/p>\n<pre><code class=\"bash\"># dd if=\/dev\/zero of=\/dev\/sdb1 bs=2024k count=1024<\/code><\/pre>\n<p>\nP\u0159edpokl\u00e1dejme, \u017ee se jedn\u00e1 o nevyu\u017eit\u00fd odd\u00edl (\/dev\/sdb1) na druh\u00e9m blokov\u00e9m za\u0159\u00edzen\u00ed (\/dev\/sdb), p\u0159ipojen\u00e9m k ob\u011bma uzl\u016fm.<\/p>\n<h4>Krok 3. Konfigurace DRBD<\/h4>\n<p>\nHlavn\u00ed konfigura\u010dn\u00ed soubor DRBD \u2014 <code>\/etc\/drbd.conf<\/code>, a dal\u0161\u00ed konfigura\u010dn\u00ed soubory lze nal\u00e9zt v adres\u00e1\u0159i <code>\/etc\/drbd.d<\/code>.<\/p>\n<p>Abychom replikovali \u00falo\u017ei\u0161t\u011b, mus\u00edme p\u0159idat pot\u0159ebn\u00e9 konfigurace do souboru <code>\/etc\/drbd.d\/global_common.conf<\/code>, kter\u00fd obsahuje glob\u00e1ln\u00ed a spole\u010dn\u00e9 \u010d\u00e1sti konfigurace DRBD, a specifikovat zdroje v <code>.res<\/code> souborech.<\/p>\n<p>Vytvo\u0159\u00edme z\u00e1lohu p\u016fvodn\u00edho souboru na obou uzlech a pot\u00e9 otev\u0159eme nov\u00fd soubor k \u00faprav\u011b (pou\u017eijte textov\u00fd editor podle sv\u00e9ho v\u00fdb\u011bru).<\/p>\n<pre><code class=\"bash\"># mv \/etc\/drbd.d\/global_common.conf \/etc\/drbd.d\/global_common.conf.orig\n# vim \/etc\/drbd.d\/global_common.conf <\/code><\/pre>\n<p>\nP\u0159idejte do obou soubor\u016f n\u00e1sleduj\u00edc\u00ed \u0159\u00e1dky:<\/p>\n<pre><code class=\"bash\">global {\n usage-count  yes;\n}\ncommon {\n net {\n  protocol C;\n }\n}<\/code><\/pre>\n<p>\nUlo\u017ete soubor a pot\u00e9 zav\u0159ete editor.<\/p>\n<p>Na chv\u00edli se zastav\u00edme u \u0159\u00e1dku protocol C. DRBD podporuje t\u0159i r\u016fzn\u00e9 re\u017eimy replikace (nap\u0159. t\u0159i \u00farovn\u011b synchronizace replikace), konkr\u00e9tn\u011b:<\/p>\n<ul>\n<li>protocol A: protokol asynchronn\u00ed replikace; nej\u010dast\u011bji pou\u017e\u00edv\u00e1n ve sc\u00e9n\u00e1\u0159\u00edch replikace na velk\u00e9 vzd\u00e1lenosti.<\/li>\n<li>protocol B: protokol polusynchronn\u00ed replikace nebo protokol synchronn\u00ed pam\u011bti.<\/li>\n<li>protocol C: obvykle pou\u017e\u00edv\u00e1n pro uzly v s\u00edt\u00edch na mal\u00e9 vzd\u00e1lenosti; je to jednozna\u010dn\u011b nej\u010dast\u011bji pou\u017e\u00edvan\u00fd replikac\u00ed protokol v nastaven\u00edch DRBD.<\/li>\n<\/ul>\n<p>\n<b>Je d\u016fle\u017eit\u00e9<\/b>: <i>v\u00fdb\u011br replikace protokolu ovliv\u0148uje dva faktory nasazen\u00ed: zaji\u0161t\u011bn\u00ed a latenci. \u0160\u00ed\u0159ka p\u00e1sma se naopak v z\u00e1sad\u011b nez\u00e1vis\u00ed na vybran\u00e9m replikace protokolu.<\/i><\/p>\n<h4>Krok 4. P\u0159id\u00e1n\u00ed zdroje<\/h4>\n<p>\nZdrojem (Resource) je souhrnn\u00fd term\u00edn, kter\u00fd se vztahuje na v\u0161echny aspekty konkr\u00e9tn\u00ed replikovan\u00e9 sady dat. N\u00e1\u0161 zdroj definujeme v souboru <code>\/etc\/drbd.d\/test.res<\/code>.<\/p>\n<p>P\u0159idejte n\u00e1sleduj\u00edc\u00ed do souboru na obou uzlech (nezapome\u0148te nahradit prom\u011bnn\u00e9 skute\u010dn\u00fdmi hodnotami pro va\u0161e prost\u0159ed\u00ed).<\/p>\n<p>V\u0161imn\u011bte si n\u00e1zv\u016f hostitel\u016f, mus\u00edme uv\u00e9st s\u00ed\u0165ov\u00e9 jm\u00e9no hostitele, kter\u00e9 lze z\u00edskat pomoc\u00ed p\u0159\u00edkazu uname <code>-n<\/code>.<\/p>\n<pre><code class=\"bash\">resource test {\n        on tecmint.tecmint.lan {\n\t\tdevice \/dev\/drbd0;\n       \t\tdisk \/dev\/sdb1;\n        \t\tmeta-disk internal;\t\n                \taddress 192.168.56.101:7789;\n        }\n        on server1.tecmint.lan  {\n\t\tdevice \/dev\/drbd0;\n        \t\tdisk \/dev\/sdb1;\n        \t\tmeta-disk internal;\n                \taddress 192.168.56.102:7789;\n        }\n}\n}<\/code><\/pre>\n<p>\nkde:<\/p>\n<ul>\n<li><i>na n\u00e1zvu hostitele<\/i>: odd\u00edl on, ke kter\u00e9mu se vztahuje vno\u0159en\u00fd konfigura\u010dn\u00ed p\u0159\u00edkaz.<\/li>\n<li><i>test<\/i>: to je n\u00e1zev nov\u00e9ho zdroje.<\/li>\n<li><i>device \/dev\/drbd0<\/i>: ud\u00e1v\u00e1 nov\u00e9 virtu\u00e1ln\u00ed blokov\u00e9 za\u0159\u00edzen\u00ed spravovan\u00e9 DRBD.<\/li>\n<li><i>disk \/dev\/sdb1<\/i>: to je odd\u00edl blokov\u00e9ho za\u0159\u00edzen\u00ed, kter\u00fd je z\u00e1lo\u017en\u00edm za\u0159\u00edzen\u00edm pro za\u0159\u00edzen\u00ed DRBD.<\/li>\n<li><i>meta-disk<\/i>: ur\u010duje, kde DRBD uchov\u00e1v\u00e1 sv\u00e1 metadata. Internal znamen\u00e1, \u017ee DRBD ukl\u00e1d\u00e1 sv\u00e1 metadata na stejn\u00e9m fyzick\u00e9m n\u00edzkolevelov\u00e9m za\u0159\u00edzen\u00ed jako skute\u010dn\u00e1 data v produkci.<\/li>\n<li><i>address<\/i>: ur\u010duje IP adresu a \u010d\u00edslo portu p\u0159\u00edslu\u0161n\u00e9ho uzlu.<\/li>\n<\/ul>\n<p>\nTak\u00e9 si uv\u011bdomte, \u017ee pokud maj\u00ed oba hostitel\u00e9 stejn\u00e9 hodnoty parametr\u016f, m\u016f\u017eete je uv\u00e9st p\u0159\u00edmo v sekci zdroj\u016f.<\/p>\n<p>Nap\u0159\u00edklad, v\u00fd\u0161e uveden\u00e1 konfigurace m\u016f\u017ee b\u00fdt p\u0159epracov\u00e1na na:<\/p>\n<pre><code class=\"bash\">resource test {\n\tdevice \/dev\/drbd0;\n\tdisk \/dev\/sdb1;\n\t\tmeta-disk internal;\t\n\t\ton tecmint.tecmint.lan {\n\t\taddress 192.168.56.101:7789;\n\t\t}\n\t\ton server1.tecmint.lan  {\n\t\taddress 192.168.56.102:7789;\n\t\t\t}\n}<\/code><\/pre>\n<p><\/p>\n<h4>Krok 5. Inicializace a spu\u0161t\u011bn\u00ed zdroje<\/h4>\n<p>\nPro interakci s DRBD budeme pou\u017e\u00edvat n\u00e1sleduj\u00edc\u00ed administra\u010dn\u00ed n\u00e1stroje (kter\u00e9 interaguj\u00ed s j\u00e1drov\u00fdm modulem pro nastaven\u00ed a spr\u00e1vu prost\u0159edk\u016f DRBD):<\/p>\n<ul>\n<li><i>drbdadm<\/i>: vysoce \u00farov\u0148ov\u00fd administra\u010dn\u00ed n\u00e1stroj DRBD.<\/li>\n<li><i>drbdsetup<\/i>: n\u00edzko\u00farov\u0148ov\u00fd administra\u010dn\u00ed n\u00e1stroj pro p\u0159ipojen\u00ed za\u0159\u00edzen\u00ed DRBD k jejich z\u00e1lo\u017en\u00edm za\u0159\u00edzen\u00edm, nastaven\u00ed p\u00e1r\u016f za\u0159\u00edzen\u00ed DRBD pro zrcadlen\u00ed jejich z\u00e1lo\u017en\u00edch za\u0159\u00edzen\u00ed a pro kontrolu konfigurace b\u011b\u017e\u00edc\u00edch za\u0159\u00edzen\u00ed DRBD.<\/li>\n<li><i>Drbdmeta<\/i>: n\u00e1stroj pro spr\u00e1vu metadat.<\/li>\n<\/ul>\n<p>\nPo p\u0159id\u00e1n\u00ed v\u0161ech po\u010d\u00e1te\u010dn\u00edch konfigurac\u00ed zdroje mus\u00edme vyvolat zdroj na obou uzlech.<\/p>\n<pre><code class=\"bash\"># drbdadm create-md test<\/code><\/pre>\n<p>\n<img decoding=\"async\" alt=\"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7\" src=\"\/wp-content\/uploads\/2020\/07\/cf084d17f60a125225f2b75668515d4f.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<i>Inicializace \u00falo\u017ei\u0161t\u011b metadat<\/i><\/p>\n<p>D\u00e1le ho mus\u00edme spustit, co\u017e p\u0159ipoj\u00ed zdroj k jeho z\u00e1lo\u017en\u00edmu za\u0159\u00edzen\u00ed, n\u00e1sledn\u011b nastav\u00ed parametry replikace a p\u0159ipoj\u00ed zdroj ke sv\u00e9mu peeru:<\/p>\n<pre><code class=\"bash\"># drbdadm up test<\/code><\/pre>\n<p>\nNyn\u00ed, pokud spust\u00edte p\u0159\u00edkaz <noindex><a rel=\"nofollow\" href=\"https:\/\/www.tecmint.com\/commands-to-collect-system-and-hardware-information-in-linux\/\">lsblk<\/a><\/noindex>, v\u0161imnete si, \u017ee za\u0159\u00edzen\u00ed\/tom DRBD drbd0 je spojeno se z\u00e1lo\u017en\u00edm za\u0159\u00edzen\u00edm <code>\/dev\/sdb1<\/code>:<\/p>\n<pre><code class=\"bash\"># lsblk<\/code><\/pre>\n<p>\n<img decoding=\"async\" alt=\"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7\" src=\"\/wp-content\/uploads\/2020\/07\/afb0be2e739c3ce71a556e78c8a55f07.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<i>Seznam blokov\u00fdch za\u0159\u00edzen\u00ed<\/i><\/p>\n<p>Chcete-li vypnout zdroj, spus\u0165te:<\/p>\n<pre><code class=\"bash\"># drbdadm down test<\/code><\/pre>\n<p>\nChcete-li zkontrolovat stav zdroje, spus\u0165te n\u00e1sleduj\u00edc\u00ed p\u0159\u00edkaz (m\u011bjte na pam\u011bti, \u017ee v t\u00e9to f\u00e1zi se o\u010dek\u00e1v\u00e1 stav disk\u016f <i>Nekonzistentn\u00ed\/Nekonzistentn\u00ed<\/i>):<\/p>\n<pre><code class=\"bash\"># drbdadm status test\nOR\n# drbdsetup status test --verbose --statistics \t#for  a more detailed status<\/code><\/pre>\n<p>\n<img decoding=\"async\" alt=\"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7\" src=\"\/wp-content\/uploads\/2020\/07\/a45da69bfbc4199ef263359b623fdd05.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<i>Kontrola stavu zdroje na u<br \/>\nz\u00e1loh<\/i><\/p>\n<h4>Krok 6: Nastaven\u00ed prim\u00e1rn\u00edho zdroje\/zdroje pro po\u010d\u00e1te\u010dn\u00ed synchronizaci za\u0159\u00edzen\u00ed<\/h4>\n<p>\nV t\u00e9to f\u00e1zi je DRBD ji\u017e p\u0159ipraven k provozu. Nyn\u00ed mus\u00edme ur\u010dit, kter\u00fd uzel m\u00e1 b\u00fdt pou\u017e\u00edv\u00e1n jako zdroj pro po\u010d\u00e1te\u010dn\u00ed synchronizaci za\u0159\u00edzen\u00ed.<\/p>\n<p>Spus\u0165te n\u00e1sleduj\u00edc\u00ed p\u0159\u00edkaz pouze na jednom uzlu, abyste zah\u00e1jili po\u010d\u00e1te\u010dn\u00ed plnou synchronizaci:<\/p>\n<pre><code class=\"bash\"># drbdadm primary --force test\n# drbdadm status test<\/code><\/pre>\n<p>\n<img decoding=\"async\" alt=\"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7\" src=\"\/wp-content\/uploads\/2020\/07\/6505d6350609e03da02f30eeafecd72c.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<i>Nastaven\u00ed prim\u00e1rn\u00edho uzlu jako po\u010d\u00e1te\u010dn\u00edho za\u0159\u00edzen\u00ed<\/i><br \/>\nPo dokon\u010den\u00ed synchronizace by m\u011bly b\u00fdt stavy obou disk\u016f UpToDate.<\/p>\n<h4>Krok 7: Testov\u00e1n\u00ed nastaven\u00ed DRBD <\/h4>\n<p>\nNakonec mus\u00edme zkontrolovat, zda bude za\u0159\u00edzen\u00ed DRBD fungovat tak, jak pot\u0159ebujeme pro ukl\u00e1d\u00e1n\u00ed replikovan\u00fdch dat. Pamatujte, \u017ee jsme pou\u017eili pr\u00e1zdn\u00fd diskov\u00fd svazek, tak\u017ee mus\u00edme vytvo\u0159it souborov\u00fd syst\u00e9m na za\u0159\u00edzen\u00ed a p\u0159imontovat ho, abychom ov\u011b\u0159ili, zda jej m\u016f\u017eeme pou\u017e\u00edt pro ukl\u00e1d\u00e1n\u00ed replikovan\u00fdch dat.<\/p>\n<p>Mus\u00edme vytvo\u0159it souborov\u00fd syst\u00e9m na za\u0159\u00edzen\u00ed pomoc\u00ed n\u00e1sleduj\u00edc\u00edho p\u0159\u00edkazu na uzlu, ze kter\u00e9ho jsme zah\u00e1jili po\u010d\u00e1te\u010dn\u00ed plnou synchronizaci (na kter\u00e9m je zdroj s prim\u00e1rn\u00ed rol\u00ed):<\/p>\n<pre><code class=\"bash\"># mkfs -t ext4 \/dev\/drbd0<\/code><\/pre>\n<p>\n<img decoding=\"async\" alt=\"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7\" src=\"\/wp-content\/uploads\/2020\/07\/32c9ac65a06993e58d9ce3b568fadca1.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<i>Vytv\u00e1\u0159\u00edme souborov\u00fd syst\u00e9m na svazku Drbd<\/i><\/p>\n<p>Pot\u00e9 jej p\u0159imontujte tak, jak je uk\u00e1z\u00e1no (m\u016f\u017eete d\u00e1t bodu montov\u00e1n\u00ed vhodn\u00e9 jm\u00e9no):<\/p>\n<pre><code class=\"bash\"># mkdir -p \/mnt\/DRDB_PRI\/\n# mount \/dev\/drbd0 \/mnt\/DRDB_PRI\/\n<\/code><\/pre>\n<p>\nNyn\u00ed zkop\u00edrujte nebo vytvo\u0159te n\u011bjak\u00e9 soubory na v\u00fd\u0161e uveden\u00e9m bod\u011b montov\u00e1n\u00ed a prove\u010fte dlouh\u00fd seznam pomoc\u00ed <noindex><a rel=\"nofollow\" href=\"https:\/\/www.tecmint.com\/tag\/linux-ls-command\/\">p\u0159\u00edkazu ls<\/a><\/noindex>:<\/p>\n<pre><code class=\"bash\"># cd \/mnt\/DRDB_PRI\/\n# ls -l <\/code><\/pre>\n<p>\n<img decoding=\"async\" alt=\"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7\" src=\"\/wp-content\/uploads\/2020\/07\/a32321e2b5c587215dc06d2b3960a4bc.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<i>Zobrazit seznam obsahu prim\u00e1rn\u00edho svazku Drbd<\/i><\/p>\n<p>D\u00e1le odmontujte za\u0159\u00edzen\u00ed (ujist\u011bte se, \u017ee mont\u00e1\u017e nen\u00ed otev\u0159en\u00e1, zm\u011b\u0148te adres\u00e1\u0159 po odmontov\u00e1n\u00ed, abyste se vyhnuli chyb\u00e1m) a zm\u011b\u0148te roli uzlu z prim\u00e1rn\u00edho na sekund\u00e1rn\u00ed:<\/p>\n<pre><code class=\"bash\"># umount \/mnt\/DRDB_PRI\/\n# cd\n# drbdadm secondary test<\/code><\/pre>\n<p>\nDruh\u00fd uzel (na kter\u00e9m je zdroj se sekund\u00e1rn\u00ed rol\u00ed) p\u0159eve\u010fte na prim\u00e1rn\u00ed, pot\u00e9 k n\u011bmu p\u0159ipojte za\u0159\u00edzen\u00ed a prove\u010fte dlouh\u00fd seznam bod\u016f montov\u00e1n\u00ed. Pokud nastaven\u00ed funguje spr\u00e1vn\u011b, m\u011bly by tam b\u00fdt v\u0161echny soubory ulo\u017een\u00e9 na svazku:<\/p>\n<pre><code class=\"bash\"># drbdadm primary test\n# mkdir -p \/mnt\/DRDB_SEC\/\n# mount \/dev\/drbd0 \/mnt\/DRDB_SEC\/\n# cd \/mnt\/DRDB_SEC\/\n# ls  -l <\/code><\/pre>\n<p>\n<img decoding=\"async\" alt=\"Nastavujeme DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7\" src=\"\/wp-content\/uploads\/2020\/07\/c54d7754a01987765a19b5bde95fc555.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<i>Kontrola nastaven\u00ed DRBD b\u011b\u017e\u00edc\u00edho na sekund\u00e1rn\u00edm uzlu.<\/i><\/p>\n<p>Pro dal\u0161\u00ed informace se obra\u0165te na referen\u010dn\u00ed str\u00e1nky administrativn\u00edch n\u00e1stroj\u016f:<\/p>\n<pre><code class=\"bash\"># man drbdadm\n# man drbdsetup\n# man drbdmeta<\/code><\/pre>\n<p>\nN\u00e1pov\u011bda: <noindex><a rel=\"nofollow\" href=\"https:\/\/docs.linbit.com\/docs\/users-guide-8.4\/\">U\u017eivatelsk\u00e1 p\u0159\u00edru\u010dka DRBD<\/a><\/noindex>.<\/p>\n<h4>Shrnut\u00ed<\/h4>\n<p>\nDRBD je mimo\u0159\u00e1dn\u011b flexibiln\u00ed a univerz\u00e1ln\u00ed, co\u017e z n\u011bj \u010din\u00ed ide\u00e1ln\u00ed \u0159e\u0161en\u00ed pro replikaci \u00falo\u017ei\u0161t\u011b, vhodn\u00e9 pro p\u0159id\u00e1n\u00ed HA prakticky do jak\u00e9koli aplikace. V tomto \u010dl\u00e1nku jsme uk\u00e1zali, jak nainstalovat DRBD na CentOS 7, a stru\u010dn\u011b demonstrovali, jak jej pou\u017e\u00edvat pro replikaci \u00falo\u017ei\u0161t\u011b. Nev\u00e1hejte se s n\u00e1mi pod\u011blit o sv\u00e9 n\u00e1zory prost\u0159ednictv\u00edm formul\u00e1\u0159e pro zp\u011btnou vazbu n\u00ed\u017ee.<\/p>\n<p>\n<noindex><a rel=\"nofollow\" href=\"https:\/\/otus.pw\/17x7\/\">Zjistit v\u00edce o kurzu.<\/a><\/noindex><\/p>\n<p>Zdroj: <a content=\"nofollow\" rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/otus\/blog\/509710\/\">habr.com<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>\u041f\u0435\u0440\u0435\u0432\u043e\u0434 \u0441\u0442\u0430\u0442\u044c\u0438 \u043f\u043e\u0434\u0433\u043e\u0442\u043e\u0432\u043b\u0435\u043d \u0432 \u043f\u0440\u0435\u0434\u0434\u0432\u0435\u0440\u0438\u0438 \u0441\u0442\u0430\u0440\u0442\u0430 \u043a\u0443\u0440\u0441\u0430 \u00ab\u0410\u0434\u043c\u0438\u043d\u0438\u0441\u0442\u0440\u0430\u0442\u043e\u0440 Linux. \u0412\u0438\u0440\u0442\u0443\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u044f \u0438 \u043a\u043b\u0430\u0441\u0442\u0435\u0440\u0438\u0437\u0430\u0446\u0438\u044f\u00bb. DRBD (Distributed Replicated Block Device \u2014 \u0440\u0430\u0441\u043f\u0440\u0435\u0434\u0435\u043b\u0451\u043d\u043d\u043e\u0435 \u0440\u0435\u043f\u043b\u0438\u0446\u0438\u0440\u0443\u0435\u043c\u043e\u0435 \u0431\u043b\u043e\u0447\u043d\u043e\u0435 \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432\u043e) \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 \u0441\u043e\u0431\u043e\u0439 \u0440\u0430\u0441\u043f\u0440\u0435\u0434\u0435\u043b\u0435\u043d\u043d\u043e\u0435, \u0433\u0438\u0431\u043a\u043e\u0435 \u0438 \u0443\u043d\u0438\u0432\u0435\u0440\u0441\u0430\u043b\u044c\u043d\u043e \u0440\u0435\u043f\u043b\u0438\u0446\u0438\u0440\u0443\u0435\u043c\u043e\u0435 \u0440\u0435\u0448\u0435\u043d\u0438\u0435 \u0445\u0440\u0430\u043d\u0435\u043d\u0438\u044f \u0434\u0430\u043d\u043d\u044b\u0445 \u0434\u043b\u044f Linux. \u041e\u043d\u043e \u043e\u0442\u0440\u0430\u0436\u0430\u0435\u0442 \u0441\u043e\u0434\u0435\u0440\u0436\u0438\u043c\u043e\u0435 \u0431\u043b\u043e\u0447\u043d\u044b\u0445 \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432, \u0442\u0430\u043a\u0438\u0445 \u043a\u0430\u043a \u0436\u0435\u0441\u0442\u043a\u0438\u0435 \u0434\u0438\u0441\u043a\u0438, \u0440\u0430\u0437\u0434\u0435\u043b\u044b, \u043b\u043e\u0433\u0438\u0447\u0435\u0441\u043a\u0438\u0435 \u0442\u043e\u043c\u0430 \u0438 \u0442.\u0434. \u043c\u0435\u0436\u0434\u0443 \u0441\u0435\u0440\u0432\u0435\u0440\u0430\u043c\u0438. \u041e\u043d\u043e \u0441\u043e\u0437\u0434\u0430\u0435\u0442 \u043a\u043e\u043f\u0438\u0438 \u0434\u0430\u043d\u043d\u044b\u0445 \u043d\u0430 [&hellip;]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":87365,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-87364","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.3 - aioseo.com -->\n\t<meta name=\"description\" content=\"\u041f\u0435\u0440\u0435\u0432\u043e\u0434 \u0441\u0442\u0430\u0442\u044c\u0438 \u043f\u043e\u0434\u0433\u043e\u0442\u043e\u0432\u043b\u0435\u043d \u0432 \u043f\u0440\u0435\u0434\u0434\u0432\u0435\u0440\u0438\u0438 \u0441\u0442\u0430\u0440\u0442\u0430 \u043a\u0443\u0440\u0441\u0430 \u00ab\u0410\u0434\u043c\u0438\u043d\u0438\u0441\u0442\u0440\u0430\u0442\u043e\u0440 Linux.\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"Yuri Gagarin\"\/>\n\t<link rel=\"canonical\" href=\"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/nastraivaem-drbd-dlya-replikaczii-hranilishha-na-dva-centos-7-servera\" \/>\n\t\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 5.0.3\" \/>\n\t\t<meta property=\"og:locale\" content=\"cs_CZ\" \/>\n\t\t<meta property=\"og:site_name\" content=\"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"\ud83e\udd47\u041d\u0430\u0441\u0442\u0440\u0430\u0438\u0432\u0430\u0435\u043c DRBD \u0434\u043b\u044f \u0440\u0435\u043f\u043b\u0438\u043a\u0430\u0446\u0438\u0438 \u0445\u0440\u0430\u043d\u0438\u043b\u0438\u0449\u0430 \u043d\u0430 \u0434\u0432\u0430 CentOS 7 \u0441\u0435\u0440\u0432\u0435\u0440\u0430 | ProHoster\" \/>\n\t\t<meta property=\"og:description\" content=\"\u041f\u0435\u0440\u0435\u0432\u043e\u0434 \u0441\u0442\u0430\u0442\u044c\u0438 \u043f\u043e\u0434\u0433\u043e\u0442\u043e\u0432\u043b\u0435\u043d \u0432 \u043f\u0440\u0435\u0434\u0434\u0432\u0435\u0440\u0438\u0438 \u0441\u0442\u0430\u0440\u0442\u0430 \u043a\u0443\u0440\u0441\u0430 \u00ab\u0410\u0434\u043c\u0438\u043d\u0438\u0441\u0442\u0440\u0430\u0442\u043e\u0440 Linux.\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/nastraivaem-drbd-dlya-replikaczii-hranilishha-na-dva-centos-7-servera\" \/>\n\t\t<meta property=\"og:image\" content=\"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg\" \/>\n\t\t<meta property=\"og:image:secure_url\" content=\"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg\" \/>\n\t\t<meta property=\"og:image:width\" content=\"350\" \/>\n\t\t<meta property=\"og:image:height\" content=\"350\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2020-07-07T11:42:29+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2020-07-07T11:42:29+00:00\" \/>\n\t\t<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/prohoster\" \/>\n\t\t<meta property=\"article:author\" content=\"https:\/\/www.facebook.com\/prohoster\" \/>\n\t\t<!-- All in One SEO -->\n\n","aioseo_head_json":{"title":"\ud83e\udd47Nastaven\u00ed DRBD pro replikaci \u00falo\u017ei\u0161t\u011b na dvou serverech CentOS 7 | ProHoster","description":"P\u0159eklad \u010dl\u00e1nku byl p\u0159ipraven p\u0159ed zah\u00e1jen\u00edm kurzu \u201eAdministr\u00e1tor Linux.","canonical_url":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/nastraivaem-drbd-dlya-replikaczii-hranilishha-na-dva-centos-7-servera","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"cs_CZ","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u041d\u0430\u0441\u0442\u0440\u0430\u0438\u0432\u0430\u0435\u043c DRBD \u0434\u043b\u044f \u0440\u0435\u043f\u043b\u0438\u043a\u0430\u0446\u0438\u0438 \u0445\u0440\u0430\u043d\u0438\u043b\u0438\u0449\u0430 \u043d\u0430 \u0434\u0432\u0430 CentOS 7 \u0441\u0435\u0440\u0432\u0435\u0440\u0430 | ProHoster","og:description":"\u041f\u0435\u0440\u0435\u0432\u043e\u0434 \u0441\u0442\u0430\u0442\u044c\u0438 \u043f\u043e\u0434\u0433\u043e\u0442\u043e\u0432\u043b\u0435\u043d \u0432 \u043f\u0440\u0435\u0434\u0434\u0432\u0435\u0440\u0438\u0438 \u0441\u0442\u0430\u0440\u0442\u0430 \u043a\u0443\u0440\u0441\u0430 \u00ab\u0410\u0434\u043c\u0438\u043d\u0438\u0441\u0442\u0440\u0430\u0442\u043e\u0440 Linux.","og:url":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/nastraivaem-drbd-dlya-replikaczii-hranilishha-na-dva-centos-7-servera","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2020-07-07T11:42:29+00:00","article:modified_time":"2020-07-07T11:42:29+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"87364","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":null,"schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"seo_analyzer_scan_date":null,"breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2021-02-28 13:52:23","updated":"2022-09-29 17:59:08","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/87364","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/comments?post=87364"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/87364\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media\/87365"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media?parent=87364"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/categories?post=87364"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/tags?post=87364"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}