{"id":33803,"date":"2019-10-31T21:54:45","date_gmt":"2019-10-31T18:54:45","guid":{"rendered":"https:\/\/prohoster.info\/blog\/on-vam-ne-drook\/"},"modified":"2019-10-31T21:54:45","modified_gmt":"2019-10-31T18:54:45","slug":"on-vam-ne-drook","status":"publish","type":"post","link":"https:\/\/prohoster.info\/ro\/blog\/administrirovanie\/on-vam-ne-drook","title":{"rendered":"El nu este Drook","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Av\u00e2nd \u00een vedere popularitatea \u00een cre\u0219tere a Rook, vreau s\u0103 discut despre capcanele \u0219i problemele care v\u0103 a\u0219teapt\u0103.<\/p>\n

Despre mine: Experien\u021b\u0103 \u00een administrarea ceph din versiunea hammer, fondator al comunit\u0103\u021bii t.me\/ceph_ro<\/a><\/noindex> pe Telegram.<\/p>\n

Pentru a nu fi acuzat de subiectivism, voi face referire la post\u0103rile acceptate pe Habr (judec\u00e2nd dup\u0103 rating) despre problemele cu ceph. M-am confruntat \u0219i eu cu cele mai multe probleme men\u021bionate \u00een aceste post\u0103ri. Linkurile c\u0103tre materialele folosite sunt la sf\u00e2r\u0219itul postului.<\/p>\n

\u00cen postarea despre Rook men\u021bion\u0103m ceph nu \u00eent\u00e2mpl\u0103tor - Rook este, \u00een esen\u021b\u0103, ceph ambalat \u00een kubernetes, ceea ce \u00eenseamn\u0103 c\u0103 mo\u0219tene\u0219te toate problemele sale. S\u0103 \u00eencepem cu problemele ceph.
\n<\/a><\/noindex><\/p>\n

Simplificarea gestion\u0103rii clusterului<\/h3>\n

\nUnul dintre avantajele Rook este confortul gestion\u0103rii ceph prin kubernetes.<\/p>\n

Cu toate acestea, ceph con\u021bine mai mult de 1000 de parametrii de configurare, \u00een timp ce prin rook putem modifica doar o mic\u0103 parte dintre ace\u0219tia.<\/p>\n

Exemplu pe Luminous
\n> ceph daemon mon.a config show | wc -l
\n1401<\/p><\/blockquote>\n

Rook se pozi\u021bioneaz\u0103 ca o modalitate convenabil\u0103 de a instala \u0219i actualiza ceph<\/b>
\nNu exist\u0103 probleme cu instalarea ceph f\u0103r\u0103 Rook - playbook-ul ansible dureaz\u0103 30 de minute s\u0103 se scrie, dar exist\u0103 o mul\u021bime de probleme cu actualizarea. <\/p>\n

Citat din postarea lui Krok<\/i><\/p>\n

Exemplu: func\u021bionarea incorect\u0103 a tunabilelor crush dup\u0103 actualizarea de la hummer la jewel<\/p>\n

> ceph osd crush show-tunables
\n{
\n\u2026
\n \u201estraw_calc_version\u201d: 1,
\n \u201eallowed_bucket_algs\u201d: 22,
\n \u201eprofile\u201d: \u201eunknown\u201d,
\n \u201eoptimal_tunables\u201d: 0,
\n\u2026
\n}<\/p><\/blockquote>\n

Dar chiar \u0219i \u00een cadrul versiunilor minore exist\u0103 probleme.<\/p>\n

Exemplu: Actualizarea 12.2.6 care duce clusterul \u00een stare de s\u0103n\u0103tate eronat\u0103 \u0219i PG-uri condi\u021bionat corupte
\nceph.com\/releases\/v12-2-8-released<\/a><\/noindex><\/p>\n

S\u0103 nu ne actualiz\u0103m, s\u0103 a\u0219tept\u0103m \u0219i s\u0103 test\u0103m? Dar totu\u0219i folosim Rook pentru confortul actualiz\u0103rilor printre altele.<\/p>\n

Dificultatea recuper\u0103rii \u00een caz de dezastru a clusterului \u00een Rook <\/h3>\n

\nExemplu: OSD-ul cade gener\u00e2nd erori. Suspecta\u021bi c\u0103 problema este unul dintre parametrii din configurare, vre\u021bi s\u0103 schimba\u021bi configura\u021bia pentru un anumit daemon, dar nu pute\u021bi, pentru c\u0103 ave\u021bi kubernetes \u0219i DaemonSet.<\/p>\n

Nu exist\u0103 alternativ\u0103. ceph tell osd.Num injectargs nu func\u021bioneaz\u0103 - OSD-ul e c\u0103zut.<\/p>\n

Dificultatea depan\u0103rii<\/h3>\n

\nPentru anumite set\u0103ri \u0219i teste de performan\u021b\u0103, este necesar s\u0103 v\u0103 conecta\u021bi direct la socket-ul daemonului osd. \u00cen cazul Rook, trebuie s\u0103 g\u0103si\u021bi containerul dorit, apoi s\u0103 intra\u021bi \u00een el, s\u0103 descoperi\u021bi absen\u021ba instrumentelor de depanare \u0219i s\u0103 fi\u021bi foarte dezam\u0103git.<\/p>\n

Dificultatea ridic\u0103rii succesive a OSD-ului<\/h3>\n

\nExemplu: OSD-ul cade din cauza OOM, \u00eencepe rebalance-ul, dup\u0103 care cad urm\u0103toarele.<\/p>\n

Solu\u021bie: Ridica\u021bi OSD-ul pe r\u00e2nd, a\u0219tepta\u021bi s\u0103 se \u00eencadreze complet \u00een cluster \u0219i ridica\u021bi urm\u0103toarele. (Mai multe detalii \u00een raportul Ceph. Anatomia dezastrului).<\/p>\n

\u00cen cazul instal\u0103rilor baremetal, acest lucru se face simplu manual, iar \u00een cazul Rook \u0219i cu un OSD pe nod problemele nu sunt mari, problemele cu ridicarea sequential\u0103 vor ap\u0103rea dac\u0103 OSD > 1 pe nod. <\/p>\n

Desigur, ele sunt rezolvabile, dar purt\u0103m Rook pentru simplificare, iar ceea ce ob\u021binem este complicare.<\/p>\n

Complexitatea stabilirii limitelor pentru demonii ceph.<\/h3>\n

\nPentru instal\u0103rile baremetal ceph este destul de u\u0219or s\u0103 se calculeze resursele necesare pentru cluster\u2014exist\u0103 formule \u0219i cercet\u0103ri disponibile. C\u00e2nd folosi\u021bi CPU-uri slabe, va trebui totu\u0219i s\u0103 face\u021bi o serie de teste de performan\u021b\u0103, s\u0103 \u00eenv\u0103\u021ba\u021bi ce este Numa, dar totul este de fapt mai simplu dec\u00e2t \u00een Rook.<\/p>\n

\u00cen cazul Rook, pe l\u00e2ng\u0103 limitele de memorie care pot fi calculate, apare \u00eentrebarea stabilirii limitei CPU.<\/p>\n

\u0218i aici va trebui s\u0103 depune\u021bi eforturi cu testele de performan\u021b\u0103. \u00cen cazul subevalu\u0103rii limitelor, ve\u021bi ob\u021bine un cluster lent, iar dac\u0103 stabili\u021bi unlimit, ve\u021bi avea o utilizare activ\u0103 a CPU-ului \u00een timpul reechilibrului, ceea ce va influen\u021ba negativ aplica\u021biile dvs. \u00een kubernetes.<\/p>\n

Probleme cu interac\u021biunea re\u021bea v1.<\/h3>\n

\nPentru ceph se recomand\u0103 utilizarea unei re\u021bele de 2x10gb. Una pentru traficul clien\u021bilor, cealalt\u0103 pentru nevoile de serviciu ale ceph (reechilibrare). Dac\u0103 folosi\u021bi ceph pe baremetal, atunci aceast\u0103 separare este u\u0219or de configurat, dar dac\u0103 utiliza\u021bi Rook, separarea pe re\u021bele v\u0103 va provoca probleme, deoarece nu orice configura\u021bie de cluster permite conectarea a dou\u0103 re\u021bele diferite \u00een pod.<\/p>\n

Probleme cu interac\u021biunea re\u021bea v2.<\/h3>\n

\nDac\u0103 renun\u021ba\u021bi la separarea re\u021belelor, atunci \u00een timpul reechilibr\u0103rii traficul ceph va umple \u00eentreaga l\u0103\u021bime de band\u0103 \u0219i aplica\u021biile dvs. \u00een kubernetes vor func\u021biona lent sau se vor opri. Pute\u021bi reduce viteza reechilibr\u0103rii ceph, dar astfel, datorit\u0103 reechilibr\u0103rii prelungite, risca\u021bi ca al doilea nod s\u0103 ias\u0103 din cluster din cauza discului sau OOM, iar acolo ave\u021bi deja o garan\u021bie de read only pe cluster.<\/p>\n

Reechilibrare \u00eendelungat\u0103 \u2014 \u00eent\u00e2rzieri lungi \u00een aplica\u021bii.<\/h3>\n

\nCitat din postarea Ceph. Anatomia dezastrului.<\/i><\/p>\n

Performan\u021ba clusterului de testare:<\/p>\n

Opera\u021bia de scriere de 4 Kbyte dureaz\u0103 1 ms, performan\u021ba este de 1000 de opera\u021bii\/secund\u0103 \u00eentr-un singur fir.<\/p>\n

Opera\u021bia de dimensiune 4 Mbyte (dimensiunea obiectului) dureaz\u0103 22 ms, performan\u021ba este de 45 de opera\u021bii\/secund\u0103.<\/p>\n

Prin urmare, atunci c\u00e2nd un domeniu din trei e\u0219ueaz\u0103, clusterul se afl\u0103 pentru o vreme \u00eentr-o stare degradat\u0103, iar jum\u0103tate dintre obiectele active sunt distribuite \u00eentre diferitele versiuni, astfel c\u0103 jum\u0103tate din opera\u021biile de scriere vor \u00eencepe cu o recuperare for\u021bat\u0103.<\/p>\n

Timpul de recuperare for\u021bat\u0103 este estimat aproximativ - opera\u021biile de scriere \u00een obiectul degradat.<\/p>\n

\u00cent\u00e2i citim 4 MB \u00een 22 ms, scriem \u00een 22 ms \u0219i apoi \u00een 1 ms scriem 4 KB de date propriu-zise. \u00cen total, 45 ms pentru o opera\u021bie de scriere \u00een obiectul degradat pe SSD, c\u00e2nd performan\u021ba normal\u0103 a fost de 1 ms - o sc\u0103dere a performan\u021bei de 45 de ori.<\/p>\n

Cu c\u00e2t procentajul obiectelor degradate este mai mare, cu at\u00e2t devine tot mai \u00eengrijor\u0103tor.<\/p><\/blockquote>\n

Astfel, viteza de rebalansare este critic\u0103 pentru func\u021bionarea corect\u0103 a clusterului.<\/p>\n

Set\u0103ri specifice pentru serverele ceph<\/h3>\n

\nCeph necesit\u0103 uneori o ajustare specific\u0103 a gazdelor. <\/p>\n

Exemplu: set\u0103rile sysctl \u0219i aceea\u0219i JumboFrame, unele dintre aceste set\u0103ri pot afecta negativ payload-ul dvs.<\/p>\n

Necesitatea real\u0103 pentru Rook r\u0103m\u00e2ne sub semnul \u00eentreb\u0103rii<\/h3>\n

\nDac\u0103 sunte\u021bi \u00een cloud, ave\u021bi un stocaj de la furnizorul de cloud, ceea ce este mult mai convenabil. <\/p>\n

Dac\u0103 v\u0103 afla\u021bi pe serverele proprii, gestionarea ceph va fi mai convenabil\u0103 f\u0103r\u0103 kubernetes. <\/p>\n

\u00cenchiria\u021bi servere de la un furnizor de g\u0103zduire de tip low cost? Atunci v\u0103 a\u0219teapt\u0103 multe probleme cu re\u021beaua, \u00eent\u00e2rzierile \u0219i l\u0103\u021bimea de band\u0103, ceea ce influen\u021beaz\u0103 evident ceph \u00een mod negativ.<\/p>\n

\u00cen total:<\/b> Implementarea kubernetes \u0219i integrarea stoc\u0103rii sunt sarcini diferite, cu premise diferite \u0219i op\u021biuni de solu\u021bii diferite - amestec\u00e2ndu-le, se face un trade-off posibil periculos \u00een favoarea uneia sau alteia. Combinarea acestor solu\u021bii va fi foarte dificil\u0103 chiar \u0219i \u00een etapa de proiectare, iar dup\u0103 aceea exist\u0103 perioada de exploatare.<\/p>\n

Lista bibliografic\u0103:<\/p>\n

Postare #1<\/a><\/noindex> Dar voi vorbi\u021bi despre Ceph... este el at\u00e2t de bun?
\nPostare #2<\/a><\/noindex> Ceph. Anatomia unui e\u0219ec
\n
Sursa: habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0412 \u0441\u0432\u044f\u0437\u0438 \u0441 \u043d\u0430\u0431\u0438\u0440\u0430\u044e\u0449\u0435\u0439 \u043f\u043e\u043f\u0443\u043b\u044f\u0440\u043d\u043e\u0441\u0442\u044c\u044e Rook \u0445\u043e\u0447\u0435\u0442\u0441\u044f \u043f\u043e\u0433\u043e\u0432\u043e\u0440\u0438\u0442\u044c \u043e \u0435\u0433\u043e \u043f\u043e\u0434\u0432\u043e\u0434\u043d\u044b\u0445 \u043a\u0430\u043c\u043d\u044f\u0445 \u0438 \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430\u0445, \u043a\u043e\u0442\u043e\u0440\u044b\u0435 \u0436\u0434\u0443\u0442 \u0432\u0430\u0441 \u043d\u0430 \u043f\u0443\u0442\u0438. \u041e \u0441\u0435\u0431\u0435: \u041e\u043f\u044b\u0442 \u0430\u0434\u043c\u0438\u043d\u0438\u0441\u0442\u0440\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f ceph \u0441 \u0432\u0435\u0440\u0441\u0438\u0438 hammer, \u043e\u0441\u043d\u043e\u0432\u0430\u0442\u0435\u043b\u044c \u043a\u043e\u043c\u044c\u044e\u043d\u0438\u0442\u0438 t.me\/ceph_ru \u0432 \u0442\u0435\u043b\u0435\u0433\u0440\u0430\u043c. \u0414\u0430\u0431\u044b \u043d\u0435 \u0431\u044b\u0442\u044c \u0433\u043e\u043b\u043e\u0441\u043b\u043e\u0432\u043d\u044b\u043c \u044f \u0431\u0443\u0434\u0443 \u0441\u0441\u044b\u043b\u0430\u0442\u044c\u0441\u044f \u043d\u0430 \u043f\u0440\u0438\u043d\u044f\u0442\u044b\u0435 \u0445\u0430\u0431\u0440\u043e\u043c (\u0441\u0443\u0434\u044f \u043f\u043e \u0440\u0435\u0439\u0442\u0438\u043d\u0433\u0443) \u043f\u043e\u0441\u0442\u044b \u043e \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430\u0445 \u0441 ceph. \u0421 \u0431\u041e\u043b\u044c\u0448\u0435\u0439 \u0447\u0430\u0441\u0442\u044c\u044e \u043f\u0440\u043e\u0431\u043b\u0435\u043c \u0432 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-33803","post","type-post","status-publish","format-standard","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\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\n","aioseo_head_json":{"title":"\ud83e\udd47Nu e\u0219ti dRook | ProHoster","description":"Av\u00e2nd \u00een vedere popularitatea tot mai mare a Rook, vreau s\u0103 discut despre capcanele \u0219i problemele care v\u0103 a\u0219teapt\u0103 pe parcurs. Despre mine: Experien\u021b\u0103 \u00een administrarea ceph din versiunea hammer, fondator al comunit\u0103\u021bii","canonical_url":"https:\/\/prohoster.info\/ro\/blog\/administrirovanie\/on-vam-ne-drook","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"ro_RO","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\u041e\u043d \u0432\u0430\u043c \u043d\u0435 \u0434Rook | ProHoster","og:description":"\u0412 \u0441\u0432\u044f\u0437\u0438 \u0441 \u043d\u0430\u0431\u0438\u0440\u0430\u044e\u0449\u0435\u0439 \u043f\u043e\u043f\u0443\u043b\u044f\u0440\u043d\u043e\u0441\u0442\u044c\u044e Rook \u0445\u043e\u0447\u0435\u0442\u0441\u044f \u043f\u043e\u0433\u043e\u0432\u043e\u0440\u0438\u0442\u044c \u043e \u0435\u0433\u043e \u043f\u043e\u0434\u0432\u043e\u0434\u043d\u044b\u0445 \u043a\u0430\u043c\u043d\u044f\u0445 \u0438 \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430\u0445, \u043a\u043e\u0442\u043e\u0440\u044b\u0435 \u0436\u0434\u0443\u0442 \u0432\u0430\u0441 \u043d\u0430 \u043f\u0443\u0442\u0438. \u041e \u0441\u0435\u0431\u0435: \u041e\u043f\u044b\u0442 \u0430\u0434\u043c\u0438\u043d\u0438\u0441\u0442\u0440\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f ceph \u0441 \u0432\u0435\u0440\u0441\u0438\u0438 hammer, \u043e\u0441\u043d\u043e\u0432\u0430\u0442\u0435\u043b\u044c \u043a\u043e\u043c\u044c\u044e\u043d\u0438\u0442\u0438","og:url":"https:\/\/prohoster.info\/ro\/blog\/administrirovanie\/on-vam-ne-drook","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":"2019-10-31T18:54:45+00:00","article:modified_time":"2019-10-31T18:54:45+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"33803","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":"2026-01-21 16:46:22","breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2021-03-01 02:33:24","updated":"2026-01-21 16:46:22","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts\/33803","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/comments?post=33803"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/posts\/33803\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/media?parent=33803"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/categories?post=33803"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/ro\/wp-json\/wp\/v2\/tags?post=33803"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}