![6 inkqubo yokonwabisa bugs ekusebenzeni kweKubernetes [kunye nesisombululo sabo]](https://prohoster.info/wp-content/plugins/wp-fastest-cache-premium/pro/images/blank.gif)
Ukutyhubela iminyaka yokusebenzisa i-Kubernetes kwimveliso, siye saqokelela amabali amaninzi anomdla okuba iibugs kumacandelo enkqubo ahlukeneyo zikhokelele kwiziphumo ezingathandekiyo kunye / okanye ezingaqondakaliyo ezichaphazela ukusebenza kwezikhongozeli kunye neepods. Kweli nqaku senze ukhetho lwezona ziqhelekileyo okanye ezinomdla. Nokuba awuzange ube nethamsanqa ngokwaneleyo lokudibana neemeko ezinjalo, ukufunda ngamabali amafutshane anjengomcuphi - ngakumbi "isandla sokuqala" - kuhlala kunomdla, akunjalo?
Ibali 1. I-Supercronic kunye ne-Docker ejingayo
Kwelinye lamaqela, ngamaxesha athile sasifumana iDocker engumkhenkce, ephazamisana nokusebenza okuqhelekileyo kweqela. Kwangelo xesha, oku kulandelayo kwabonwa kwiilog zeDocker:
level=error msg="containerd: start init process" error="exit status 2: "runtime/cgo: pthread_create failed: No space left on device
SIGABRT: abort
PC=0x7f31b811a428 m=0
goroutine 0 [idle]:
goroutine 1 [running]:
runtime.systemstack_switch() /usr/local/go/src/runtime/asm_amd64.s:252 fp=0xc420026768 sp=0xc420026760
runtime.main() /usr/local/go/src/runtime/proc.go:127 +0x6c fp=0xc4200267c0 sp=0xc420026768
runtime.goexit() /usr/local/go/src/runtime/asm_amd64.s:2086 +0x1 fp=0xc4200267c8 sp=0xc4200267c0
goroutine 17 [syscall, locked to thread]:
runtime.goexit() /usr/local/go/src/runtime/asm_amd64.s:2086 +0x1
β¦
Eyona nto esinomdla kuyo ngale mpazamo ngumyalezo: pthread_create failed: No space left on device. Ukufunda ngokukhawuleza yachaza ukuba i-Docker ayinakukwazi ukwenza inkqubo, yiyo loo nto iba ngumkhenkce ngamaxesha athile.
Ekubekeni iliso, lo mfanekiso ulandelayo uhambelana nento eyenzekayo:
Imeko efanayo ibonwa kwezinye iindawo:
Kwiindawo ezifanayo sibona:
root@kube-node-1 ~ # ps auxfww | grep curl -c
19782
root@kube-node-1 ~ # ps auxfww | grep curl | head
root 16688 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 17398 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 16852 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 9473 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 4664 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 30571 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 24113 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 16475 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 7176 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>
root 1090 0.0 0.0 0 0 ? Z Feb06 0:00 | _ [curl] <defunct>Kwavela ukuba le ndlela yokuziphatha iyisiphumo sokusebenza kwepod (isixhobo se-Go esisisebenzisayo ukuqhuba imisebenzi yecron kwiipod):
_ docker-containerd-shim 833b60bb9ff4c669bb413b898a5fd142a57a21695e5dc42684235df907825567 /var/run/docker/libcontainerd/833b60bb9ff4c669bb413b898a5fd142a57a21695e5dc42684235df907825567 docker-runc
| _ /usr/local/bin/supercronic -json /crontabs/cron
| _ /usr/bin/newrelic-daemon --agent --pidfile /var/run/newrelic-daemon.pid --logfile /dev/stderr --port /run/newrelic.sock --tls --define utilization.detect_aws=true --define utilization.detect_azure=true --define utilization.detect_gcp=true --define utilization.detect_pcf=true --define utilization.detect_docker=true
| | _ /usr/bin/newrelic-daemon --agent --pidfile /var/run/newrelic-daemon.pid --logfile /dev/stderr --port /run/newrelic.sock --tls --define utilization.detect_aws=true --define utilization.detect_azure=true --define utilization.detect_gcp=true --define utilization.detect_pcf=true --define utilization.detect_docker=true -no-pidfile
| _ [newrelic-daemon] <defunct>
| _ [curl] <defunct>
| _ [curl] <defunct>
| _ [curl] <defunct>
β¦Ingxaki yile: xa umsebenzi uqhutywa kwi-supercronic, inkqubo eyenziwa yiyo ayikwazi ukuphelisa ngokuchanekileyo, ukujika ube .
Qaphela:: Ukuchaneka ngakumbi, iinkqubo ziveliswa yimisebenzi yecron, kodwa i-supercronic ayikho inkqubo ye-init kwaye ayikwazi "ukwamkela" iinkqubo eziveliswa ngabantwana bayo. Xa iimpawu ze-SIGHUP okanye ze-SIGTERM ziphakanyisiwe, azidluliselwa kwiinkqubo zomntwana, okubangela ukuba iinkqubo zomntwana zingapheli kwaye zihlale kwimeko ye-zombie. Unokufunda ngakumbi ngayo yonke le nto, umzekelo, kwi .
Kukho iindlela ezimbini zokusombulula iingxaki:
- Njengomsebenzi wexeshana - nyusa inani le-PIDs kwinkqubo ngexesha elinye:
/proc/sys/kernel/pid_max (since Linux 2.5.34) This file specifies the value at which PIDs wrap around (i.e., the value in this file is one greater than the maximum PID). PIDs greater than this value are not alloβ cated; thus, the value in this file also acts as a system-wide limit on the total number of processes and threads. The default value for this file, 32768, results in the same range of PIDs as on earlier kernels - Okanye uqalise imisebenzi kwi-supercronic hayi ngokuthe ngqo, kodwa usebenzisa okufanayo , ekwazi ukuphelisa iinkqubo ngokuchanekileyo kwaye ingavelisi i-zombies.
Ibali 2. "Zombies" xa ucima iqela
UKubelet waqala ukusebenzisa i-CPU eninzi:
Akukho mntu uya kuyithanda le nto, ngoko sazixhobisa waza waqalisa ukujamelana nengxaki. Iziphumo zophando zaba ngolu hlobo lulandelayo:
- UKubelet uchitha ngaphezulu kwesithathu sexesha lakhe le-CPU etsala idatha yememori kuwo onke amaqela:
- Kuluhlu lokuposa lwabaphuhlisi bekernel onokulufumana . Ngamafutshane, inqaku liza kuthi: iifayile ezahlukeneyo zetmpfs kunye nezinye izinto ezifanayo azisuswanga ngokupheleleyo kwinkqubo xa ucima iqela, into ebizwa zombi. Kungekudala okanye kamva baya kususwa kwi-cache yephepha, kodwa kukho imemori eninzi kumncedisi kwaye i-kernel ayiboni inqaku ekuchitheni ixesha ekucimeni. Yiyo loo nto beqhubeka befumba. Kutheni kusenzeka oku? Lo ngumncedisi onemisebenzi yecron ehlala idala imisebenzi emitsha, kunye neepods ezintsha. Ke, amaqela amatsha enzelwe izikhongozeli ezikuzo, ezithi zicinywe ngokukhawuleza.
- Kutheni i-cAdvisor kwi-kubelet ichitha ixesha elininzi kangaka? Oku kulula ukukubona ngokuphunyezwa okulula
time cat /sys/fs/cgroup/memory/memory.stat. Ukuba kumatshini ophilileyo umsebenzi uthatha imizuzwana eyi-0,01, ngoko kwi-cron02 eyingxaki ithatha imizuzwana eyi-1,2. Into kukuba i-cAdvisor, efunda idatha kwi-sysfs ngokucothayo, izama ukuthathela ingqalelo imemori esetyenziswa kumaqela e-zombie. - Ukususa ngenkani i-zombies, sizame ukucoca ii-caches njengoko kucetyiswa kwi-LKML:
sync; echo 3 > /proc/sys/vm/drop_caches, - kodwa i-kernel yajika yaba nzima kwaye yatshitshisa imoto.
Kwenziwe ntoni? Ingxaki iyalungiswa (, kunye nenkcazo bona ) ukuhlaziya i-Linux kernel kuguqulelo lwe-4.16.
Imbali 3. Systemd kunye nokunyuka kwayo
Kwakhona, i-kubelet itya izixhobo ezininzi kakhulu kwezinye iindawo, kodwa ngeli xesha kudla inkumbulo eninzi kakhulu:
Kuye kwavela ukuba kukho ingxaki kwi-systemd esetyenziswa ku-Ubuntu 16.04, kwaye iyenzeka xa ulawula ii-mounts ezenzelwe uxhulumaniso. subPath ukusuka kwiConfigMap okanye imfihlo. Emva kokuba i-pod iwugqibile umsebenzi wayo inkonzo ye-systemd kunye nenkonzo yayo yokunyuka ihlala kwinkqubo. Ngokuhamba kwexesha, inani elikhulu lazo liqokelelana. Kukho nemiba kulo mxholo:
- ;
- .
...eyokugqibela ebhekisa kwi-PR kwi-systemd: (umcimbi kwi-systemd - ).
Ingxaki ayisekho ku-Ubuntu 18.04, kodwa ukuba ufuna ukuqhubeka usebenzisa Ubuntu 16.04, unokufumana i-workaround yethu kwesi sihloko siluncedo.
Ke senze le DaemonSet ilandelayo:
---
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
labels:
app: systemd-slices-cleaner
name: systemd-slices-cleaner
namespace: kube-system
spec:
updateStrategy:
type: RollingUpdate
selector:
matchLabels:
app: systemd-slices-cleaner
template:
metadata:
labels:
app: systemd-slices-cleaner
spec:
containers:
- command:
- /usr/local/bin/supercronic
- -json
- /app/crontab
Image: private-registry.org/systemd-slices-cleaner/systemd-slices-cleaner:v0.1.0
imagePullPolicy: Always
name: systemd-slices-cleaner
resources: {}
securityContext:
privileged: true
volumeMounts:
- name: systemd
mountPath: /run/systemd/private
- name: docker
mountPath: /run/docker.sock
- name: systemd-etc
mountPath: /etc/systemd
- name: systemd-run
mountPath: /run/systemd/system/
- name: lsb-release
mountPath: /etc/lsb-release-host
imagePullSecrets:
- name: antiopa-registry
priorityClassName: cluster-low
tolerations:
- operator: Exists
volumes:
- name: systemd
hostPath:
path: /run/systemd/private
- name: docker
hostPath:
path: /run/docker.sock
- name: systemd-etc
hostPath:
path: /etc/systemd
- name: systemd-run
hostPath:
path: /run/systemd/system/
- name: lsb-release
hostPath:
path: /etc/lsb-release... kwaye isebenzisa iskripthi esilandelayo:
#!/bin/bash
# we will work only on xenial
hostrelease="/etc/lsb-release-host"
test -f ${hostrelease} && grep xenial ${hostrelease} > /dev/null || exit 0
# sleeping max 30 minutes to dispense load on kube-nodes
sleep $((RANDOM % 1800))
stoppedCount=0
# counting actual subpath units in systemd
countBefore=$(systemctl list-units | grep subpath | grep "run-" | wc -l)
# let's go check each unit
for unit in $(systemctl list-units | grep subpath | grep "run-" | awk '{print $1}'); do
# finding description file for unit (to find out docker container, who born this unit)
DropFile=$(systemctl status ${unit} | grep Drop | awk -F': ' '{print $2}')
# reading uuid for docker container from description file
DockerContainerId=$(cat ${DropFile}/50-Description.conf | awk '{print $5}' | cut -d/ -f6)
# checking container status (running or not)
checkFlag=$(docker ps | grep -c ${DockerContainerId})
# if container not running, we will stop unit
if [[ ${checkFlag} -eq 0 ]]; then
echo "Stopping unit ${unit}"
# stoping unit in action
systemctl stop $unit
# just counter for logs
((stoppedCount++))
# logging current progress
echo "Stopped ${stoppedCount} systemd units out of ${countBefore}"
fi
done... kwaye ibaleka yonke imizuzu emi-5 isebenzisa i-supercronic ekhankanywe ngaphambili. I-Dockerfile yayo ibonakala ngolu hlobo:
FROM ubuntu:16.04
COPY rootfs /
WORKDIR /app
RUN apt-get update &&
apt-get upgrade -y &&
apt-get install -y gnupg curl apt-transport-https software-properties-common wget
RUN add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu xenial stable" &&
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | apt-key add - &&
apt-get update &&
apt-get install -y docker-ce=17.03.0*
RUN wget https://github.com/aptible/supercronic/releases/download/v0.1.6/supercronic-linux-amd64 -O
/usr/local/bin/supercronic && chmod +x /usr/local/bin/supercronic
ENTRYPOINT ["/bin/bash", "-c", "/usr/local/bin/supercronic -json /app/crontab"]Ibali 4. Ukhuphiswano xa ucwangcisa iipod
Kwaphawulwa ukuba: ukuba sinepod ebekwe kwindawo kwaye umfanekiso wayo uphonswe ixesha elide, ke enye i-pod "ebetha" i-node efanayo iya ngokulula. ayiqalisi ukutsala umfanekiso wepod entsha. Endaweni yoko, ilinda de kutsalwe umfanekiso wepod yangaphambili. Ngenxa yoko, i-pod esele icwangcisiwe kwaye umfanekiso wayo unokukhutshelwa ngomzuzu nje uya kuphelela kwisimo se. containerCreating.
Iziganeko ziya kujongeka ngolu hlobo:
Normal Pulling 8m kubelet, ip-10-241-44-128.ap-northeast-1.compute.internal pulling image "registry.example.com/infra/openvpn/openvpn:master"Kuvela oko umfanekiso omnye osuka kwirejistri ecothayo unokuthintela ukusasazwa kwindawo nganye.
Ngelishwa, akukho ndlela zininzi zokuphuma kwimeko:
- Zama ukusebenzisa iRegistry yakho yeDocker ngokuthe ngqo kwiqela okanye ngokuthe ngqo kunye neqela (umzekelo, iGitLab Registry, Nexus, njl.);
- Sebenzisa eziluncedo ezifana .
Ibali lesi-5. Iindibano zijinga ngenxa yokungakhumbuli
Ngexesha lokusebenza kwezicelo ezahlukeneyo, siye sadibana nemeko apho i-node iyeka ngokupheleleyo ukufikeleleka: i-SSH ayiphenduli, zonke iidaemoni zokubeka iliso ziyawa, kwaye ke akukho nto (okanye phantse akukho nto) engaqhelekanga kwiilogi.
Ndiza kukuxelela kwimifanekiso ndisebenzisa umzekelo wendawo enye apho iMongoDB yayisebenza khona.
Yile nto ibonakala ngathi i-atop Π΄ΠΎ iingozi:
Kwaye njengale - ΠΏΠΎΡΠ»Π΅ iingozi:
Ekubekeni iliso, kukho ukutsiba okubukhali, apho i-node iyeka ukufumaneka:
Ke, ukusuka kwiscreenshots kuyacaca ukuba:
- I-RAM kumatshini isondele ekupheleni;
- Kukho ukutsiba okubukhali ekusebenziseni i-RAM, emva koko ukufikelela kumatshini wonke kukhubaziwe ngokukhawuleza;
- Umsebenzi omkhulu ufika kwi-Mongo, enyanzelisa inkqubo ye-DBMS ukuba isebenzise imemori eninzi kwaye ifunde ngokukhutheleyo kwidiski.
Kuyavela ukuba ukuba iLinux iphelelwa yinkumbulo yasimahla (uxinzelelo lwenkumbulo luseta) kwaye akukho swap, emva koko. Π΄ΠΎ Xa umbulali we-OOM efika, isenzo sokulinganisa sinokuvela phakathi kokuphosa amaphepha kwi-cache yephepha kunye nokuwabhala kwakhona kwidiski. Oku kwenziwa ngu kswapd, ekhulula ngenkalipho amaphepha enkumbulo amaninzi kangangoko kunikezelo olulandelayo.
Ngelishwa, ngomthwalo omkhulu we-I/O odityaniswe nenani elincinci lememori yasimahla, kswapd iba ngumqobo wenkqubo yonke, ngenxa yokuba zibotshelelwe kuyo zonke ulwabiwo (iimpazamo zephepha) lamaphepha enkumbulo kwindlela. Oku kunokuqhubeka ixesha elide kakhulu ukuba iinkqubo azifuni kuphinda zisebenzise imemori, kodwa zilungiswe kumda we-OOM-killer enzonzobileni.
Umbuzo wendalo ngulo: kutheni umbulali we-OOM eze kade kangaka? Kwi-iteration yayo yangoku, umbulali we-OOM usisidenge kakhulu: iya kubulala inkqubo kuphela xa umzamo wokwabela iphepha lememori ungaphumeleli, oko kukuthi. ukuba iphepha liyasilela. Oku akwenzeki ixesha elide, kuba kswapd ngokukhalipha ikhulula inkumbulo yamaphepha, ilahla indawo yokugcina yephepha (idiski yonke I/O kwindlela, enyanisweni) emva kwidiski. Ngeenkcukacha ezingakumbi, ngenkcazo yamanyathelo afunekayo ukuphelisa iingxaki ezinjalo kwi-kernel, unokufunda .
Lo kuziphatha ngeLinux kernel 4.6+.
Ibali 6. Iipods zixinga kwimo elindileyo
Kwamanye amaqela, apho kukho iipods ezininzi ezisebenzayo, saqala ukuqaphela ukuba uninzi lwazo "zixhoma" ixesha elide kurhulumente. Pending, nangona iziqulathi zeDocker ngokwazo sele zisebenza kwiinodi kwaye zinokusetyenzwa ngesandla.
Ngaphezu koko, kwi describe akukho nto iphosakeleyo:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 1m default-scheduler Successfully assigned sphinx-0 to ss-dev-kub07
Normal SuccessfulAttachVolume 1m attachdetach-controller AttachVolume.Attach succeeded for volume "pvc-6aaad34f-ad10-11e8-a44c-52540035a73b"
Normal SuccessfulMountVolume 1m kubelet, ss-dev-kub07 MountVolume.SetUp succeeded for volume "sphinx-config"
Normal SuccessfulMountVolume 1m kubelet, ss-dev-kub07 MountVolume.SetUp succeeded for volume "default-token-fzcsf"
Normal SuccessfulMountVolume 49s (x2 over 51s) kubelet, ss-dev-kub07 MountVolume.SetUp succeeded for volume "pvc-6aaad34f-ad10-11e8-a44c-52540035a73b"
Normal Pulled 43s kubelet, ss-dev-kub07 Container image "registry.example.com/infra/sphinx-exporter/sphinx-indexer:v1" already present on machine
Normal Created 43s kubelet, ss-dev-kub07 Created container
Normal Started 43s kubelet, ss-dev-kub07 Started container
Normal Pulled 43s kubelet, ss-dev-kub07 Container image "registry.example.com/infra/sphinx/sphinx:v1" already present on machine
Normal Created 42s kubelet, ss-dev-kub07 Created container
Normal Started 42s kubelet, ss-dev-kub07 Started containerEmva kokumba okuthile, senze ukucinga ukuba i-kubelet ayinalo ixesha lokuthumela lonke ulwazi malunga nemeko yeepods kunye novavanyo lokulungela / ukulungela kwiseva ye-API.
Kwaye emva kokufunda uncedo, sifumene ezi parameters zilandelayo:
--kube-api-qps - QPS to use while talking with kubernetes apiserver (default 5)
--kube-api-burst - Burst to use while talking with kubernetes apiserver (default 10)
--event-qps - If > 0, limit event creations per second to this value. If 0, unlimited. (default 5)
--event-burst - Maximum size of a bursty event records, temporarily allows event records to burst to this number, while still not exceeding event-qps. Only used if --event-qps > 0 (default 10)
--registry-qps - If > 0, limit registry pull QPS to this value.
--registry-burst - Maximum size of bursty pulls, temporarily allows pulls to burst to this number, while still not exceeding registry-qps. Only used if --registry-qps > 0 (default 10)Njengoko kubonakala, amaxabiso angagqibekanga mancinci kakhulu, kwaye kwi-90% bagubungela zonke iimfuno ... Nangona kunjalo, kwimeko yethu oku kwakunganele. Ngoko ke, sibeka la maxabiso alandelayo:
--event-qps=30 --event-burst=40 --kube-api-burst=40 --kube-api-qps=30 --registry-qps=30 --registry-burst=40... kwaye saqala kwakhona i-kubelets, emva koko sabona lo mfanekiso ulandelayo kwiigrafu zeefowuni kwiseva ye-API:
... kwaye ewe, yonke into yaqala ukundiza!
PS
Ngoncedo lwabo ekuqokeleleni iibugs kunye nokulungiselela eli nqaku, ndivakalisa umbulelo wam onzulu kwiinjineli ezininzi zenkampani yethu, ngakumbi kumlingane wam kwiqela lethu leR&D uAndrey Klimentyev ().
Iipps
Funda nakwibhlog yethu:
- «».
- Iingcebiso zeKubernetes kunye namaqhinga okuhamba:
- Β«";
- Β«";
- Β«";
- «».
umthombo: www.habr.com