{"id":38965,"date":"2019-10-31T22:27:03","date_gmt":"2019-10-31T19:27:03","guid":{"rendered":"https:\/\/prohoster.info\/blog\/liveness-probes-v-kubernetes-mogut-byt-opasny\/"},"modified":"2019-10-31T22:27:03","modified_gmt":"2019-10-31T19:27:03","slug":"liveness-probes-v-kubernetes-mogut-byt-opasny","status":"publish","type":"post","link":"https:\/\/prohoster.info\/et\/blog\/administrirovanie\/liveness-probes-v-kubernetes-mogut-byt-opasny","title":{"rendered":"Kuberneteses olevad Liveness probes v\u00f5ivad olla ohtlikud","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<p><i><b>M\u00e4rkus t\u00f5lke kohta.<\/b>: Zalando juhtiv insener Henning Jacobs on korduvalt m\u00e4rganud Kubernetes'i kasutajatel probleeme liveness (ja readiness) probe'ide m\u00f5istmise ja nende \u00f5ige rakendamisega. Seet\u00f5ttu koondas ta oma m\u00f5tted sellesse l\u00fchikesse m\u00e4rkusesse, mis aja jooksul muutub K8si dokumentatsiooni osaks.<\/i><\/p>\n<p><img decoding=\"async\" alt=\"Kuberneteses olevad Liveness probes v\u00f5ivad olla ohtlikud\" src=\"\/wp-content\/uploads\/2019\/10\/b246e18dadd582889382f306508135a8.jpg\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\nKubernetes'is tuntud kui <i>liveness probes<\/i> <i>(st. s\u00f5na otseses m\u00f5ttes \u00abeluj\u00f5udluse testid\u00bb \u2014 m\u00e4rk. t\u00f5lk.)<\/i>, v\u00f5ivad olla \u00fcsna ohtlikud. Soovitan neid v\u00f5imaluse korral v\u00e4ltida: eranditeks on ainult juhtumid, kui need on t\u00f5eliselt vajalikud ja te t\u00e4ielikult m\u00f5istate nende kasutamise erip\u00e4ra ja tagaj\u00e4rgi. Selles publikatsioonis r\u00e4\u00e4gitakse liveness- ja readiness-kontrollidest ning tuuakse v\u00e4lja, millal <i>asub<\/i> ja millal neid ei tohiks rakendada.<noindex><a rel=\"nofollow\" name=\"habracut\"><\/a><\/noindex><\/p>\n<p>Minu kolleeg Sandor jagas hiljuti Twitteris k\u00f5ige sagedasemaid vigu, millega ta kokku puutub, sealhulgas readiness\/liveness probe'ide kasutamisel.<\/p>\n<p><noindex><a rel=\"nofollow\" href=\"https:\/\/twitter.com\/sszuecs\/status\/1175377157343907840\"><img decoding=\"async\" alt=\"Kuberneteses olevad Liveness probes v\u00f5ivad olla ohtlikud\" src=\"\/wp-content\/uploads\/2019\/10\/8bc2e834e77e2b51baf06d2465a97b4f.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/a><\/noindex><\/p>\n<p>Vale seadistamine <code>livenessProbe<\/code> v\u00f5ib halvendada k\u00f5rge koormuse olukordi (lumepalliefekt + potentsiaalselt pikk konteineri\/rakenduse k\u00e4ivitamine) ja p\u00f5hjustada teisi negatiivseid tagaj\u00e4rgi, nagu s\u00f5ltuvuste kokkuvarisemine <i>(vt ka <noindex><a rel=\"nofollow\" href=\"https:\/\/srcco.de\/posts\/k3s-outage-traefik-acme-lets-encrypt-local-path.html\">minu hiljutine artikkel<\/a><\/noindex> K3s+ACME kombineeritud p\u00e4ringute piiramisest)<\/i>. Veel hullem on see, kui liveness probe on kombineeritud s\u00f5ltuvuste tervisekontrolliga, milleks on v\u00e4line andmebaas. <b>\u00fcks andmebaasi rike taask\u00e4ivitab k\u00f5ik teie konteinerid<\/b>!<\/p>\n<p>\u00dcks peamine s\u00f5num <i>\u00ab\u00c4rge kasutage liveness probe'e\u00bb<\/i> antud juhul aitab v\u00e4he, seega vaatame, milleks readiness- ja liveness-kontrollid on m\u00f5eldud. <\/p>\n<p><i>M\u00e4rkus: enamik allpool toodud testidest oli algselt kaasatud Zalando arendajate sisemisse dokumentatsiooni.<\/i><\/p>\n<h2>Readiness ja Liveness kontrollid<\/h2>\n<p>\nKubernetes pakub kahte olulist mehhanismi, mida nimetatakse <noindex><a rel=\"nofollow\" href=\"https:\/\/kubernetes.io\/docs\/tasks\/configure-pod-container\/configure-liveness-readiness-probes\/\">liveness probes ja readiness probes<\/a><\/noindex>. Need t\u00e4idavad perioodiliselt teatud toimingut \u2014 n\u00e4iteks saadavad HTTP-p\u00e4ringu, avavad TCP-\u00fchenduse v\u00f5i k\u00e4ivitavad k\u00e4su konteineris \u2014 et kinnitada, et rakendus t\u00f6\u00f6tab korralikult.<\/p>\n<p>Kubernetes kasutab <b>readiness probes<\/b>, et m\u00f5ista, millal konteiner on valmis liiklust vastu v\u00f5tma. Pod loetakse t\u00f6\u00f6k\u00f5lblikuks, kui k\u00f5ik selle konteinerid on valmis. \u00dcks selle mehhanismi rakendamise viise on j\u00e4lgida, milliseid pod'e kasutatakse Kubernetes'i teenuste (ja eriti Ingress'i) taustatekohtadeks.<\/p>\n<p><b>Elamise kontrollid<\/b> aitavad Kubernetes\u2019il m\u00f5ista, millal on aeg konteinerit taask\u00e4ivitada. N\u00e4iteks v\u00f5imaldab selline kontroll haarata deadlock\u2019ist, kus rakendus \u201ehakkab\u201d paigale. Konteineri taask\u00e4ivitamine sellises seisundis aitab rakendust liigutada surnud punktist edasi, hoolimata vigadest, kuid see v\u00f5ib samuti viia kaskaadsete t\u00f5rgeteni (vt allpool).<\/p>\n<p>Kui proovite rakenduse v\u00e4rskendust juurutada, mis ei l\u00e4hi elamise \/ valmiduse kontrollidest, j\u00e4\u00e4b selle juurutamine seisma, kuna Kubernetes ootab staatust <code>Valmis<\/code> k\u00f5ikide pod'ide puhul.<\/p>\n<h2>N\u00e4ide<\/h2>\n<p>\nSiin on n\u00e4ide valmiduse kontrollist, mis kontrollib teed <code>\/health<\/code> HTTP kaudu vaikeseadetega (<i>intervall<\/i>: 10 sekundit, <i>aegumine<\/i>: 1 sekund, <i>eduka k\u00fcnnise<\/i>: 1, <i>eba\u00f5nnestumise k\u00fcnnise<\/i>: 3):<\/p>\n<pre><code class=\"plaintext\"># \u0447\u0430\u0441\u0442\u044c \u043e\u0431\u0449\u0435\u0433\u043e \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u044f deployment'\u0430\/\u0441\u0442\u0435\u043a\u0430\npodTemplate:\n  spec:\n    containers:\n    - name: my-container\n      # ...\n      readinessProbe:\n        httpGet:\n          path: \/health\n          port: 8080<\/code><\/pre>\n<p><\/p>\n<h2>Soovitused<\/h2>\n<p><\/p>\n<ol>\n<li> HTTP l\u00f5pp-punktiga (nt REST) mikroteenuste puhul <b>m\u00e4\u00e4rake alati valmiduse kontroll<\/b>, mis kontrollib, kas rakendus (pod) on valmis liiklust vastu v\u00f5tma.<\/li>\n<li> Veenduge, et valmiduse kontroll <b>katab veebiserveri tegeliku porti valmiduse<\/b>:\n<ul>\n<li> kasutades haldusotstarbeliseks portides, mida nimetatakse \u201eadmin\u201d v\u00f5i \u201emanagement\u201d (nt 9090), <code>readinessProbe<\/code>, veenduge, et l\u00f5pp-punkt tagastab OK, ainult kui peamine HTTP-port (n\u00e4iteks 8080) on valmis liiklust vastu v\u00f5tma*;\n<p><i>* Olen teadlik v\u00e4hemalt \u00fchest juhtumist Zalando\u2019s, kus seda ei juhtunud, see t\u00e4hendab <code>readinessProbe<\/code> et kontrolliti \u201ehaldus\u201d porti, kuid server ise ei hakanud t\u00f6\u00f6le, kuna vahem\u00e4lu laadimisega olid probleeme.<\/i><\/li>\n<li> readiness probe'i lisamine eraldi porti v\u00f5ib viia selleni, et peamise pordi koormus ei kajastu tervisekontrollis (st serveri l\u00f5imede bassein on t\u00e4is, kuid tervisekontroll n\u00e4itab endiselt, et k\u00f5ik on korras).<\/li>\n<\/ul>\n<\/li>\n<li> Veenduge, et <b>valmiduse kontroll h\u00f5lmab andmebaasi initsialiseerimist \/ migratsiooni<\/b>;\n<ul>\n<li> k\u00f5ige lihtsam viis selle saavutamiseks on p\u00f6\u00f6rduda HTTP-serveri poole alles p\u00e4rast initsialiseerimise (nt andmebaasi migratsiooni) l\u00f5ppu; <noindex><a rel=\"nofollow\" href=\"https:\/\/flywaydb.org\/\">Flyway<\/a><\/noindex> jne.); see t\u00e4hendab, et selle asemel, et muuta tervisekontrolli staatust, \u00e4rge k\u00e4ivitage veebiserverit enne, kui andmebaasi migreerimine on l\u00f5pule viidud*.\n<p><i>* Samuti on v\u00f5imalik k\u00e4ivitada andmebaasi migreerimisi init-konteineritest v\u00e4ljaspool pod'i. Ma olen endiselt enesesisemise rakenduste pooldaja, st rakenduse konteiner, mis teab, kuidas andmebaasi \u00f5igele seisundile viia, ilma v\u00e4lise koordineerimiseta.<\/i><\/li>\n<\/ul>\n<\/li>\n<li> Kasutage <code>httpGet<\/code> readiness-kontrollide jaoks t\u00fc\u00fcpiliste tervisekontrollide l\u00f5pp-punktide kaudu (nt <code>\/health<\/code>).<\/li>\n<li> <b>Tutvu vaikev\u00e4\u00e4rtustega kontrolli parameetrite osas.<\/b> (<code>interval: 10s<\/code>, <code>timeout: 1s<\/code>, <code>successThreshold: 1<\/code>, <code>failureThreshold: 3<\/code>):\n<ul>\n<li> vaikev\u00e4\u00e4rtused t\u00e4hendavad, et pod muutub <i>not-ready<\/i> umbes 30 sekundi p\u00e4rast (3 eba\u00f5nnestunud tervisekontrolli).<\/li>\n<\/ul>\n<\/li>\n<li> Kasutage eraldi porti \u2018admin\u2019 v\u00f5i \u2018management\u2019 jaoks, kui tehnoloogiline virn (n\u00e4iteks Java\/Spring) seda v\u00f5imaldab, et eraldada tervise ja metoodika haldamine tavaliikluse eest:\n<ul>\n<li> aga \u00e4rge unustage punkti 2.<\/li>\n<\/ul>\n<\/li>\n<li> Vajadusel v\u00f5ib valmisoleku kontrolli kasutada teadmiste kaldumiseks\/vahem\u00e4lu laadimiseks ja v\u00e4ljastada olekukoodi 503, kuni konteiner ei ole \u2018soojenenud\u2019:\n<ul>\n<li> soovitan tuttavaks saada uue kontrolliga <code>startupProbe<\/code>, <noindex><a rel=\"nofollow\" href=\"https:\/\/sysdig.com\/blog\/whats-new-kubernetes-1-16\/\">mis tuli v\u00e4lja versioonis 1.16<\/a><\/noindex> <i>(oleme sellest kirjutanud vene keeles. <noindex><a rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/flant\/blog\/467477\/\">siin<\/a><\/noindex> \u2014 toimetaja m\u00e4rkus)<\/i>.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<p><\/p>\n<h2>Hoiatused<\/h2>\n<p><\/p>\n<ol>\n<li> <b>\u00c4rge toetuge v\u00e4listele s\u00f5ltuvustele<\/b> (nagu andmete ladustamine) valmisoleku\/eluviiside testide l\u00e4biviimisel \u2014 see v\u00f5ib p\u00f5hjustada kaskaadseid eba\u00f5nnestumisi:\n<ul>\n<li> v\u00f5tame n\u00e4iteks stateful teenuse RESTiga, millel on 10 pod'i, mis s\u00f5ltuvad \u00fchest Postgresi andmebaasist: kui kontroll s\u00f5ltub t\u00f6\u00f6tavast \u00fchendusest andmebaasiga, v\u00f5ivad k\u00f5ik 10 pod'i kokku kukkuda, kui\u00fchenduses tekib viivitus \u2014 see l\u00f5ppeb tavaliselt halvemini kui v\u00f5iks;<\/li>\n<li> pange t\u00e4hele, et Spring Data kontrollib vaikimisi andmebaasiga \u00fchendust*;\n<p><i>* See on Spring Data Redis vaikimisi k\u00e4itumine (v\u00e4hemalt oli see nii, kui ma viimati kontrollisin), mis viis \"katastroofilise\" t\u00f5rkeni: kui Redis j\u00e4i l\u00fchikeseks ajaks k\u00e4tte saamata, kukkusid k\u00f5ik pod'id \"\u00e4ra\".<\/i><\/li>\n<li> \"v\u00e4line\" t\u00e4hendus v\u00f5ib selles kontekstis t\u00e4hendada ka teisi sama rakenduse pod'e, st ideaaljuhul ei tohiks kontroll s\u00f5ltuda teise klastrite pod'i seisundist, et v\u00e4ltida kaskaadseid eba\u00f5nnestumisi:\n<ul>\n<li> tulemused v\u00f5ivad varieeruda rakenduste puhul, millel on jagatud olek (nt m\u00e4lus hoitav vahem\u00e4lu pod'ides).<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li> <b>\u00c4rge kasutage eluviisi kontrolli<\/b> pod'ide jaoks (v\u00e4lja arvatud juhud, kui need on t\u00f5eliselt vajalikud ja olete t\u00e4ielikult teadlikud nende kasutamise erip\u00e4rast ja tagaj\u00e4rgedest):\n<ul>\n<li> liveness probe v\u00f5ib aidata taastada 'hangunud' konteinerid, kuid kuna te kontrollite t\u00e4ielikult oma rakendust, ei tohiks selliseid asju nagu 'hangunud' protsessid ja deadlock'id ideaaljuhul juhtuda: parem alternatiiv on rakenduse tahtlik kokkuvarisemine ja selle naasmine eelnevalt stabiilsesse olekusse;<\/li>\n<li> eba\u00f5nnestunud liveness probe toob kaasa konteineri taask\u00e4ivitamise, mis v\u00f5ib potentsiaalselt s\u00fcvendada laadimisega seotud vigu: konteineri taask\u00e4ivitamine p\u00f5hjustab seiskumise (v\u00e4hemalt rakenduse k\u00e4ivitamise ajal, \u00fctleme, \u00fcle 30 sekundi), tekitades uusi vigu, suurendades koormust teistele konteineritele ja t\u00f5stes nende rikke t\u00f5en\u00e4osust jne;<\/li>\n<li> liveness-proovid koos v\u00e4lise s\u00f5ltuvusega on halvim v\u00f5imalik kombinatsioon, mis \u00e4hvardab kaskaadsete t\u00f5rgete ohtu: isegi v\u00e4ike viivitus andmebaasi k\u00fcljelt v\u00f5ib p\u00f5hjustada k\u00f5igi teie konteinerite taask\u00e4ivitamise!<\/li>\n<\/ul>\n<\/li>\n<li> liveness- ja readiness-proovide parameetrid <b>peavad olema erinevad<\/b>:\n<ul>\n<li> liveness probe'i v\u00f5ib kasutada sama health check'iga, kuid k\u00f5rgema aktiveerimissummega (<code>failureThreshold<\/code>), n\u00e4iteks m\u00e4\u00e4rata olek <i>not-ready<\/i> p\u00e4rast 3 katset ja arvata, et liveness probe eba\u00f5nnestus p\u00e4rast 10 katset;<\/li>\n<\/ul>\n<\/li>\n<li> <b>\u00c4rge kasutage exec-proove<\/b>, kuna nendega on seotud tuntud probleemid, mis p\u00f5hjustavad zombiprotsesside tekkimist:\n<ul>\n<li> detailid: vt. <noindex><a rel=\"nofollow\" href=\"https:\/\/www.youtube.com\/watch?v=QKI-JRs2RIE\">Datadogi spetsialistide ettekannet<\/a><\/noindex>.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<p><\/p>\n<h2>Elulookirjeldus<\/h2>\n<p><\/p>\n<ul>\n<li> Kasutage readiness probe'e, et m\u00e4\u00e4rata, millal pod on valmis liiklust vastu v\u00f5tma.<\/li>\n<li> Kasutage liveness proove ainult siis, kui need on t\u00f5eliselt vajalikud.<\/li>\n<li> Valesti kasutatud readiness\/liveness probes v\u00f5ivad p\u00f5hjustada k\u00e4ttesaadavuse v\u00e4henemist ja kaskaadseid t\u00f5rkeid.<\/li>\n<\/ul>\n<p>\n<noindex><a rel=\"nofollow\" href=\"https:\/\/twitter.com\/sszuecs\/status\/1175655221382529025\"><img decoding=\"async\" alt=\"Kuberneteses olevad Liveness probes v\u00f5ivad olla ohtlikud\" src=\"\/wp-content\/uploads\/2019\/10\/8c212c41d6e69cd515a85d2b6100aaed.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/a><\/noindex><\/p>\n<h2>T\u00e4iendavad materjalid teema kohta<\/h2>\n<p><\/p>\n<ul>\n<li> <noindex><a rel=\"nofollow\" href=\"https:\/\/kubernetes.io\/docs\/tasks\/configure-pod-container\/configure-liveness-readiness-probes\/\">Kubernetes docs: Liveness ja Readiness Proovide konfigureerimine<\/a><\/noindex>;<\/li>\n<li> <noindex><a rel=\"nofollow\" href=\"https:\/\/blog.colinbreck.com\/kubernetes-liveness-and-readiness-probes-revisited-how-to-avoid-shooting-yourself-in-the-other-foot\/\">Kubernetes Liveness ja Readiness Proovid uuesti vaatamisel: Kuidas mitte endale jalga tulistada<\/a><\/noindex>;<\/li>\n<li> <noindex><a rel=\"nofollow\" href=\"https:\/\/keepingitclassless.net\/2018\/12\/december-4-nre-labs-outage-post-mortem\/\">NRE Labs'i katkestuse j\u00e4reldused<\/a><\/noindex> (k\u00e4tkeb ka livenessProbe'i).<\/li>\n<\/ul>\n<p><\/p>\n<h2>Uuendus nr 1 alates 2019-09-29<\/h2>\n<p>\n<noindex><a rel=\"nofollow\" href=\"https:\/\/twitter.com\/BarrWill1\/status\/1178144162526453760\">Init-konteinerite kohta andmebaasi migreerimisel<\/a><\/noindex>: lisatud jalus.<\/p>\n<p><noindex><a rel=\"nofollow\" href=\"https:\/\/twitter.com\/ejc3\/status\/1178077779293683713\">EJ tuletas mulle meelde<\/a><\/noindex> PDB-st: \u00fcks liveness-proovide muresid on koordinatsiooni puudumine pod'ide vahel. Kuberneteses on <noindex><a rel=\"nofollow\" href=\"https:\/\/kubernetes.io\/docs\/tasks\/run-application\/configure-pdb\/\">Pod Disruption Budgets (PDB)<\/a><\/noindex> rakenduse paralleelsete rikete arvu piiramiseks, mida see v\u00f5ib kogeda, kuid proovide puhul ei arvestata PDB-d. Ideaalis saame k\u00e4skida K8s: \u201eTaask\u00e4ivita \u00fcks pod, kui selle proov eba\u00f5nnestub, kuid \u00e4ra taask\u00e4ivita k\u00f5iki, et mitte olukorda halvendada\u201d.<\/p>\n<p><noindex><a rel=\"nofollow\" href=\"https:\/\/twitter.com\/bboreham\/status\/1178083887991398400\">Bryan v\u00e4ljendas seda suurep\u00e4raselt<\/a><\/noindex>: \u201eKasutage elususe proove, kui teate t\u00e4pselt, et <b>parim asi, mida teha, on rakendus \u201etapmine\u201c<\/b>(\u00e4rge \u00fcle pingutage).<\/p>\n<p><noindex><a rel=\"nofollow\" href=\"https:\/\/twitter.com\/bboreham\/status\/1178207929540972544\"><img decoding=\"async\" alt=\"Kuberneteses olevad Liveness probes v\u00f5ivad olla ohtlikud\" src=\"\/wp-content\/uploads\/2019\/10\/524122a63bd4acd950bf9fc8aeeb45be.jpg\" style=\"display:block;margin: 0 auto;\" \/><\/a><\/noindex><\/p>\n<h2>Uuendus nr 2, 29.09.2019<\/h2>\n<p>\n<noindex><a rel=\"nofollow\" href=\"https:\/\/twitter.com\/Guillaume_Swiss\/status\/1178258781152563200\">Seoses dokumentatsiooni lugemisega enne kasutamist<\/a><\/noindex>: l\u00f5in vastava taotluse (<noindex><a rel=\"nofollow\" href=\"https:\/\/github.com\/kubernetes\/website\/issues\/16607\">feature request<\/a><\/noindex>) elususe proove k\u00e4sitleva dokumentatsiooni t\u00e4iustamiseks.<\/p>\n<h2>P.S. t\u00f5lkijalt<\/h2>\n<p>\nLugege ka meie blogist:<\/p>\n<ul>\n<li> \u00ab<noindex><a rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/flant\/blog\/415393\/\">Kubernetes: podi elu<\/a><\/noindex>\u00bb;<\/li>\n<li> \u00ab<noindex><a rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/flant\/blog\/425085\/\">Google'i versiooni j\u00e4rgi 7 parimat praktikat konteinerite kasutamiseks<\/a><\/noindex>\u00bb;<\/li>\n<li> \u00ab<noindex><a rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/flant\/blog\/353272\/\">7 konteinerip\u00f5histe rakenduste projekteerimise p\u00f5him\u00f5tet<\/a><\/noindex>\u00bb.<\/li>\n<\/ul>\n<p>Allikas: <a content=\"nofollow\" rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/flant\/blog\/470958\/\">habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>\u041f\u0440\u0438\u043c. \u043f\u0435\u0440\u0435\u0432.: \u0412\u0435\u0434\u0443\u0449\u0438\u0439 \u0438\u043d\u0436\u0435\u043d\u0435\u0440 \u0438\u0437 \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u0438 Zalando \u2014 Henning Jacobs \u2014 \u043d\u0435 \u0440\u0430\u0437 \u0437\u0430\u043c\u0435\u0447\u0430\u043b \u0443 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u0435\u0439 Kubernetes \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u044b \u0432 \u043f\u043e\u043d\u0438\u043c\u0430\u043d\u0438\u0438 \u043f\u0440\u0435\u0434\u043d\u0430\u0437\u043d\u0430\u0447\u0435\u043d\u0438\u044f liveness (\u0438 readiness) probes \u0438 \u0438\u0445 \u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u043e\u0433\u043e \u043f\u0440\u0438\u043c\u0435\u043d\u0435\u043d\u0438\u044f. \u041f\u043e\u0441\u0435\u043c\u0443 \u043e\u043d \u0441\u043e\u0431\u0440\u0430\u043b \u0441\u0432\u043e\u0438 \u043c\u044b\u0441\u043b\u0438 \u0432 \u044d\u0442\u0443 \u0451\u043c\u043a\u0443\u044e \u0437\u0430\u043c\u0435\u0442\u043a\u0443, \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u0441\u043e \u0432\u0440\u0435\u043c\u0435\u043d\u0435\u043c \u0441\u0442\u0430\u043d\u0435\u0442 \u0447\u0430\u0441\u0442\u044c\u044e \u0434\u043e\u043a\u0443\u043c\u0435\u043d\u0442\u0430\u0446\u0438\u0438 K8s. \u041f\u0440\u043e\u0432\u0435\u0440\u043a\u0438 \u0441\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u044f, \u0438\u0437\u0432\u0435\u0441\u0442\u043d\u044b\u0435 \u0432 Kubernetes \u043a\u0430\u043a liveness probes (\u0442.\u0435., \u0434\u043e\u0441\u043b\u043e\u0432\u043d\u043e, [&hellip;]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":29232,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-38965","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.2.1 - aioseo.com -->\n\t<meta name=\"description\" content=\"\u041f\u0440\u0438\u043c. \u043f\u0435\u0440\u0435\u0432.: \u0412\u0435\u0434\u0443\u0449\u0438\u0439 \u0438\u043d\u0436\u0435\u043d\u0435\u0440 \u0438\u0437 \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u0438 Zalando \u2014 Henning Jacobs \u2014 \u043d\u0435 \u0440\u0430\u0437 \u0437\u0430\u043c\u0435\u0447\u0430\u043b \u0443 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u0435\u0439 Kubernetes 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