Deploy Kafka with ZooKeeper on Portworx
Apache Kafka is a distributed event streaming platform for real-time data, using ZooKeeper for broker coordination, metadata management, and cluster state consistency. This page provides instructions for deploying Apache Kafka and ZooKeeper with Portworx Enterprise on Kubernetes.
note
ZooKeeper's role has been replaced by KRaft (Kafka Raft), an internal consensus protocol that manages metadata directly within Kafka brokers. All new Kafka 4.0 clusters use KRaft mode by default. ZooKeeper-based clusters are now officially deprecated and unsupported. For existing ZooKeeper-based clusters, Kafka provides migration tools (introduced in version 3.5) to transition metadata to KRaft mode.
To deploy Kafka with ZooKeeper on Portworx, complete the following collection of tasks:
- Create a StorageClass for dynamic provisioning.
- Deploy ZooKeeper for cluster state consistency.
- Deploy Kafka for configuring event streaming platform
- Verify Setup by creating a topic and consuming message from it.
Create a StorageClass
Portworx provides volume(s) to ZooKeeper as well as Kafka.
- Create
portworx-sc.yamlwith Portworx as the provisioner.
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: portworx-sc
provisioner: pxd.portworx.com
parameters:
repl: "1"
priority_io: "high"
group: "zk_vg"
fg: "true"
---
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: portworx-sc-rep2
provisioner: pxd.portworx.com
parameters:
repl: "2"
priority_io: "high"
group: "kafka_vg"
fg: "true"
---
- Apply the configuration on your cluster.
kubectl apply -f portworx-sc.yaml
Deploy ZooKeeper
A StatefulSet in Kubernetes requires a headless service to provide network identity to the pods it creates. A headless service is also needed when Kafka is deployed. A headless service does not use a cluster IP. For information on headless services, read this article.
This is also important for the later stages of the deployment of Kafka, since, we would need to access ZooKeeper via the DNS records that are created by this headless service.
- Create a file called
zookeeper-all.yamlwith the following content:
apiVersion: v1
kind: Service
metadata:
name: zk-headless
labels:
app: zk-headless
spec:
ports:
- port: 2888
name: server
- port: 3888
name: leader-election
clusterIP: None
selector:
app: zk
---
apiVersion: v1
kind: ConfigMap
metadata:
name: zk-config
data:
ensemble: "zk-0;zk-1;zk-2"
jvm.heap: "2G"
tick: "2000"
init: "10"
sync: "5"
client.cnxns: "60"
snap.retain: "3"
purge.interval: "1"
---
apiVersion: policy/v1beta1
kind: PodDisruptionBudget
metadata:
name: zk-budget
spec:
selector:
matchLabels:
app: zk
minAvailable: 2
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: zk
spec:
selector:
matchLabels:
app: zk
serviceName: zk-headless
replicas: 3
template:
metadata:
labels:
app: zk
annotations:
pod.alpha.kubernetes.io/initialized: "true"
spec:
# Use the stork scheduler to enable more efficient placement of the pods
schedulerName: stork
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: px/running
operator: NotIn
values:
- "false"
- key: px/enabled
operator: NotIn
values:
- "false"
podAntiAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- key: "app"
operator: In
values:
- zk-headless
topologyKey: "kubernetes.io/hostname"
containers:
- name: k8szk
imagePullPolicy: Always
image: gcr.io/google_samples/k8szk:v1
ports:
- containerPort: 2181
name: client
- containerPort: 2888
name: server
- containerPort: 3888
name: leader-election
env:
- name : ZK_ENSEMBLE
valueFrom:
configMapKeyRef:
name: zk-config
key: ensemble
- name : ZK_HEAP_SIZE
valueFrom:
configMapKeyRef:
name: zk-config
key: jvm.heap
- name : ZK_TICK_TIME
valueFrom:
configMapKeyRef:
name: zk-config
key: tick
- name : ZK_INIT_LIMIT
valueFrom:
configMapKeyRef:
name: zk-config
key: init
- name : ZK_SYNC_LIMIT
valueFrom:
configMapKeyRef:
name: zk-config
key: tick
- name : ZK_MAX_CLIENT_CNXNS
valueFrom:
configMapKeyRef:
name: zk-config
key: client.cnxns
- name: ZK_SNAP_RETAIN_COUNT
valueFrom:
configMapKeyRef:
name: zk-config
key: snap.retain
- name: ZK_PURGE_INTERVAL
valueFrom:
configMapKeyRef:
name: zk-config
key: purge.interval
- name: ZK_CLIENT_PORT
value: "2181"
- name: ZK_SERVER_PORT
value: "2888"
- name: ZK_ELECTION_PORT
value: "3888"
command:
- sh
- -c
- zkGenConfig.sh && zkServer.sh start-foreground
readinessProbe:
exec:
command:
- "zkOk.sh"
initialDelaySeconds: 15
timeoutSeconds: 5
livenessProbe:
exec:
command:
- "zkOk.sh"
initialDelaySeconds: 15
timeoutSeconds: 5
volumeMounts:
- name: datadir
mountPath: /var/lib/zookeeper
securityContext:
runAsUser: 1000
fsGroup: 1000
volumeClaimTemplates:
- metadata:
name: datadir
spec:
storageClassName: portworx-sc
accessModes: [ "ReadWriteOnce" ]
resources:
requests:
storage: 2Gi
- Apply this configuration
kubectl apply -f zookeeper-all.yaml
- Verify that the ZooKeeper pods are running with provisioned Portworx volumes.
kubectl get pods
NAME READY STATUS RESTARTS AGE
zk-0 1/1 Running 0 23h
zk-1 1/1 Running 0 23h
zk-2 1/1 Running 0 23h
kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESSMODES STORAGECLASS AGE
data-zk-0 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc 23h
data-zk-1 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc 23h
data-zk-2 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc 23h
kubectl get sts
NAME DESIRED CURRENT AGE
zk 3 3 1d
pxctl volume inspect pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002
Volume : 816480848884203913
Name : pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002
Size : 3.0 GiB
Format : ext4
HA : 1
IO Priority : LOW
Creation time : Aug 7 14:07:16 UTC 2017
Shared : no
Status : up
State : Attached: k8s-0
Device Path : /dev/pxd/pxd816480848884203913
Labels : pvc=data-zk-0
Reads : 59
Reads MS : 252
Bytes Read : 466944
Writes : 816
Writes MS : 3608
Bytes Written : 53018624
IOs in progress : 0
Bytes used : 65 MiB
Replica sets on nodes:
Set 0
Node : 10.140.0.5
- Verify that the ZooKeeper ensemble is working.
kubectl exec zk-0 -- /opt/zookeeper/bin/zkCli.sh create /foo bar
WATCHER::
WatchedEvent state:SyncConnected type:None path:null
Created /foo
kubectl exec zk-2 -- /opt/zookeeper/bin/zkCli.sh get /foo
WATCHER::
WatchedEvent state:SyncConnected type:None path:null
cZxid = 0x10000004d
bar
ctime = Tue Aug 08 14:18:11 UTC 2017
mZxid = 0x10000004d
mtime = Tue Aug 08 14:18:11 UTC 2017
pZxid = 0x10000004d
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 3
numChildren = 0
Deploy Kafka
-
Retrieve the FQDN of each ZooKeeper Pod by entering the following command:
for i in 0 1 2; do kubectl exec zk-$i -- hostname -f; donezk-0.zk-headless.default.svc.cluster.local
zk-1.zk-headless.default.svc.cluster.local
zk-2.zk-headless.default.svc.cluster.local -
Download the kafka-all.yaml file and use the
zookeeper.connectproperty to specify your ZooKeeper hosts as a comma-separated list. -
Apply the spec by entering the following command:
kubectl apply -f kafka-all.yaml -
This step is optional. Run the following
kubectl applycommand if you are installing Kafka with ZooKeeper on AWS EKS:kubectl apply -f https://raw.githubusercontent.com/Yolean/kubernetes-kafka/master/rbac-namespace-default/node-reader.ymlclusterrole.rbac.authorization.k8s.io/node-reader created
clusterrolebinding.rbac.authorization.k8s.io/kafka-node-reader created -
Verify that Kafka resources are created on the cluster.
kubectl get pods -l "app=kafka" -n kafka -w
NAME READY STATUS RESTARTS AGE
kafka-0 1/1 Running 0 17s
kafka-1 0/1 Init:0/1 0 3s
kafka-1 0/1 Init:0/1 0 4s
kafka-1 0/1 PodInitializing 0 5s
kafka-1 0/1 Running 0 6s
kafka-1 1/1 Running 0 9s
kafka-2 0/1 Pending 0 0s
kafka-2 0/1 Pending 0 1s
kafka-2 0/1 Pending 0 3s
kafka-2 0/1 Init:0/1 0 4s
kafka-2 0/1 Init:0/1 0 6s
kafka-2 0/1 PodInitializing 0 8s
kafka-2 0/1 Running 0 9s
kafka-2 1/1 Running 0 15s
kubectl get pvc -n kafka
NAME STATUS VOLUME CAPACITY ACCESSMODES STORAGECLASS AGE
data-kafka-0 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 1m
data-kafka-1 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 57s
data-kafka-2 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 48s
pxctl volume list
ID NAME SIZE HA SHARED ENCRYPTED IO_PRIORITY SCALE STATUS
523341158152507227 pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3 GiB 1 no no LOW 0 up - attached on 10.140.0.4
816480848884203913 pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3 GiB 1 no no LOW 0 up - attached on 10.140.0.5
262949240358217536 pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3 GiB 2 no no LOW 0 up - attached on 10.140.0.3
733731201475618092 pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3 GiB 2 no no LOW 0 up - attached on 10.140.0.5
360663112422496357 pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3 GiB 2 no no LOW 0 up - attached on 10.140.0.4
168733173797215691 pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3 GiB 1 no no LOW 0 up - attached on 10.140.0.3
pxctl volume inspect pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002
Volume : 262949240358217536
Name : pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002
Size : 3.0 GiB
Format : ext4
HA : 2
IO Priority : LOW
Creation time : Aug 8 15:10:51 UTC 2017
Shared : no
Status : up
State : Attached: k8s-2
Device Path : /dev/pxd/pxd262949240358217536
Labels : pvc=data-kafka-0
Reads : 37
Reads MS : 8
Bytes Read : 372736
Writes : 354
Writes MS : 3096
Bytes Written : 53641216
IOs in progress : 0
Bytes used : 65 MiB
Replica sets on nodes:
Set 0
Node : 10.140.0.5
Node : 10.140.0.3
Verify Setup
- Find the Kafka brokers
for i in 0 1 2; do kubectl exec -n kafka kafka-$i -- hostname -f; done
kafka-0.broker.kafka.svc.cluster.local
kafka-1.broker.kafka.svc.cluster.local
kafka-2.broker.kafka.svc.cluster.local
- Create a topic with 3 partitions and which has a replication factor of 3
kubectl exec -n kafka -it kafka-0 -- bash
bin/kafka-topics.sh --zookeeper zk-headless.default.svc.cluster.local:2181 --create --if-not-exists --topic px-kafka-topic --partitions 3 --replication-factor 3
Created topic "px-kafka-topic".
bin/kafka-topics.sh --list --zookeeper zk-headless.default.svc.cluster.local:2181
px-kafka-topic
bin/kafka-topics.sh --describe --zookeeper zk-headless.default.svc.cluster.local:2181 --topic px-kafka-topic
Topic:px-kafka-topic PartitionCount:3 ReplicationFactor:3 Configs:
Topic: px-kafka-topic Partition: 0 Leader: 0 Replicas: 0,1,2 Isr: 0,1,2
Topic: px-kafka-topic Partition: 1 Leader: 1 Replicas: 1,2,0 Isr: 1,2,0
Topic: px-kafka-topic Partition: 2 Leader: 2 Replicas: 2,0,1 Isr: 2,0,1
- Publish messages on the topic
bin/kafka-console-producer.sh --broker-list kafka-0.broker.kafka.svc.cluster.local:9092,kafka-1.broker.kafka.svc.cluster.local:9092,kafka-2.broker.kafka.svc.cluster.local:9092 --topic px-kafka-topic
>Hello Kubernetes!
>This is Portworx saying hello
>Kafka says, I am just a messenger
- Consume messages from the topic
bin/kafka-console-consumer.sh --zookeeper zk-headless.default.svc.cluster.local:2181 —topic px-kafka-topic --from-beginning
This is Portworx saying hello
Hello Kubernetes!
Kafka says, I am just a messenger
Verify Scaling
Portworx Enterprise runs as a DaemonSet in Kubernetes. Hence when you add a new node to your kuberentes cluster you do not need to explicitly run Portworx on it.
The Portworx cluster before scaling the Kubernetes nodes.
pxctl cluster list
Cluster ID: px-kafka-cluster
Cluster UUID: xxxxxxxx-xxxx-xxxx-xxxx-52d914ff39d2
Status: OK
Nodes in the cluster:
ID DATA IP CPU MEM TOTAL MEM FREE CONTAINERS VERSION STATUS
k8s-0 10.140.0.5 8.717949 3.9 GB 2.3 GB N/A 1.2.9-17d16e4 Online
k8s-1 10.140.0.3 4.081633 3.9 GB 2.2 GB N/A 1.2.9-17d16e4 Online
k8s-2 10.140.0.4 9.5 3.9 GB 2.2 GB N/A 1.2.9-17d16e4 Online
kubectl get nodes -o wide
NAME STATUS AGE VERSION EXTERNAL-IP OS-IMAGE KERNEL-VERSION
k8s-0 Ready 2d v1.7.0 <none> Ubuntu 16.10 4.8.0-56-generic
k8s-1 Ready 2d v1.7.0 <none> Ubuntu 16.10 4.8.0-56-generic
k8s-2 Ready 2d v1.7.0 <none> Ubuntu 16.10 4.8.0-56-generic
k8s-3 Ready 19h v1.7.0 <none> Ubuntu 16.10 4.8.0-56-generic
k8s-master Ready 2d v1.7.0 <none> Ubuntu 16.10 4.8.0-56-generic
Portworx scales along with your cluster.
pxctl status
Status: PX is operational
License: Trial (expires in 28 days)
Node ID: k8s-1
IP: 10.140.0.4
Local Storage Pool: 1 pool
POOL IO_PRIORITY RAID_LEVEL USABLE USED STATUS ZONE REGION
0 MEDIUM raid0 10 GiB 594 MiB Online default default
Local Storage Devices: 1 device
Device Path Media Type Size Last-Scan
0:1 /dev/sdb STORAGE_MEDIUM_SSD 10 GiB 07 Aug 17 12:48 UTC
total - 10 GiB
Cluster Summary
Cluster ID: px-kafka-cluster
Cluster UUID: 8xxxxxxxx-xxxx-xxxx-xxxx-f99420435a90
IP ID Used Capacity Status
10.140.0.4 k8s-1 594 MiB 10 GiB Online (This node)
10.140.0.3 k8s-2 594 MiB 10 GiB Online
10.140.0.5 k8s-0 655 MiB 10 GiB Online
10.140.0.6 k8s-3 338 MiB 10 GiB Online
Global Storage Pool
Total Used : 2.1 GiB
Total Capacity : 40 GiB
pxctl cluster list
Cluster ID: px-kafka-cluster
Cluster UUID: xxxxxxxx-xxxx-xxxx-xxxx-52d914ff39d2
Status: OK
Nodes in the cluster:
ID DATA IP CPU MEM TOTAL MEM FREE CONTAINERS VERSION STATUS
k8s-1 10.140.0.4 8.163265 3.9 GB 2.2 GB N/A 1.2.9-17d16e4 Online
k8s-2 10.140.0.3 6.565657 3.9 GB 2.2 GB N/A 1.2.9-17d16e4 Online
k8s-0 10.140.0.5 4.102564 3.9 GB 2.3 GB N/A 1.2.9-17d16e4 Online
k8s-3 10.140.0.6 4.040404 3.9 GB 3.4 GB N/A 1.2.9-17d16e4 Online
Scale the Kafka cluster.
kubectl scale -n kafka sts kafka --replicas=4
statefulset "kafka" scaled
kubectl get pods -n kafka -l "app=kafka" -w
NAME READY STATUS RESTARTS AGE
kafka-0 1/1 Running 0 3h
kafka-1 1/1 Running 0 3h
kafka-2 1/1 Running 0 3h
kafka-3 0/1 PodInitializing 0 24s
kafka-3 0/1 Running 0 32s
kafka-3 1/1 Running 0 34s
kubectl get pvc -n kafka
NAME STATUS VOLUME CAPACITY ACCESSMODES STORAGECLASS AGE
data-kafka-0 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 3h
data-kafka-1 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 3h
data-kafka-2 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 3h
data-kafka-3 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 6m
Verify that the newly created kafka broker is part of the cluster.
kubectl exec -n kafka -it kafka-0 -- bash
zkCli.sh
You'll see a prompt similar to this:
[zk: localhost:2181(CONNECTED) 0]
Next, type:
ls /brokers/ids
[0, 1, 2, 3]
ls /brokers/topics
[px-kafka-topic]
get /brokers/ids/3
{"listener_security_protocol_map":{"PLAINTEXT":"PLAINTEXT"},"endpoints":["PLAINTEXT://kafka-3.broker.kafka.svc.cluster.local:9092"],"jmx_port":-1,"host":"kafka-3.broker.kafka.svc.cluster.local","timestamp":"1502217586002","port":9092,"version":4}
cZxid = 0x1000000e9
ctime = Tue Aug 08 18:39:46 UTC 2017
mZxid = 0x1000000e9
mtime = Tue Aug 08 18:39:46 UTC 2017
pZxid = 0x1000000e9
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x25dbd0e499e000b
dataLength = 246
numChildren = 0
Verify Pod and Node Failover
Pod Failover for ZooKeeper
Killing the ZooKeeper Java process in the container terminates the pod. You could alternatively delete the pod as well. The Portworx volumes provide durable storage to the ZooKeeper pods which are run as a StatefulSet. Get the earlier inserted value from ZooKeeper to verify the same.
kubectl exec zk-0 -- pkill java
kubectl get pod -w -l "app=zk"
NAME READY STATUS RESTARTS AGE
zk-0 1/1 Running 0 1d
zk-1 1/1 Running 0 1d
zk-2 1/1 Running 0 1d
zk-0 0/1 Error 0 1d
zk-0 0/1 Running 1 1d
zk-0 1/1 Running 1 1d
kubectl exec zk-0 -- zkCli.sh get /foo
WATCHER::
WatchedEvent state:SyncConnected type:None path:null
bar
cZxid = 0x10000004d
ctime = Tue Aug 08 14:18:11 UTC 2017
mZxid = 0x10000004d
mtime = Tue Aug 08 14:18:11 UTC 2017
pZxid = 0x10000004d
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 3
numChildren = 0
Pod Failover for Kafka
Find the hosts of the running kafka cluster, cordon a node so that pods are scheduled on it. Kill a kafka pod and notice that it is scheduled on a newer node, joining the cluster back again with durable storage which is backed by the Portworx volume.
kubectl get pods -n kafka -o wide
NAME READY STATUS RESTARTS AGE IP NODE
kafka-0 1/1 Running 0 21h 10.0.160.3 k8s-2
kafka-1 1/1 Running 0 21h 10.0.192.3 k8s-0
kafka-2 1/1 Running 0 21h 10.0.64.4 k8s-1
kafka-3 1/1 Running 0 18h 10.0.112.1 k8s-3
kubectl cordon k8s-0
node "k8s-0" cordoned
kubectl get nodes
NAME STATUS AGE VERSION
k8s-0 Ready,SchedulingDisabled 2d v1.7.0
k8s-1 Ready 2d v1.7.0
k8s-2 Ready 2d v1.7.0
k8s-3 Ready 19h v1.7.0
k8s-master Ready 2d v1.7.0
kubectl get pvc -n kafka | grep data-kafka-1
data-kafka-1 Bound pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3Gi RWO portworx-sc-rep2 22h
/opt/pwx/bin/pxctl volume list | grep pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002
733731201475618092 pvc-xxxxxxxx-xxxx-xxxx-xxxx-42010a8c0002 3 GiB 2 no no LOW 0 up - attached on 10.140.0.5
kubectl exec -n kafka -it kafka-0 -- bash
bin/kafka-topics.sh --describe --zookeeper zk-headless.default.svc.cluster.local:2181 --topic px-kafka-topic
Topic:px-kafka-topic PartitionCount:3 ReplicationFactor:3 Configs:
Topic: px-kafka-topic Partition: 0 Leader: 0 Replicas: 0,1,2 Isr: 0,1,2
Topic: px-kafka-topic Partition: 1 Leader: 1 Replicas: 1,2,0 Isr: 1,2,0
Topic: px-kafka-topic Partition: 2 Leader: 2 Replicas: 2,0,1 Isr: 2,0,1
kubectl delete po/kafka-1 -n kafka
pod "kafka-1" deleted
kubectl get pods -n kafka -w
NAME READY STATUS RESTARTS AGE
kafka-0 1/1 Running 0 22h
kafka-1 0/1 Terminating 0 22h
kafka-2 1/1 Running 0 22h
kafka-3 1/1 Running 0 18h
kafka-1 0/1 Terminating 0 22h
kafka-1 0/1 Terminating 0 22h
kafka-1 0/1 Pending 0 0s
kafka-1 0/1 Pending 0 0s
kafka-1 0/1 Init:0/1 0 0s
kafka-1 0/1 Init:0/1 0 2s
kafka-1 0/1 PodInitializing 0 3s
kafka-1 0/1 Running 0 5s
kafka-1 1/1 Running 0 11s
kubectl get pods -n kafka -o wide
NAME READY STATUS RESTARTS AGE IP NODE
kafka-0 1/1 Running 0 22h 10.0.160.3 k8s-2
kafka-1 1/1 Running 0 1m 10.0.112.2 k8s-3
kafka-2 1/1 Running 0 22h 10.0.64.4 k8s-1
kafka-3 1/1 Running 0 18h 10.0.112.1 k8s-3
bin/kafka-topics.sh --describe --zookeeper zk-headless.default.svc.cluster.local:2181 --topic px-kafka-topic
Topic:px-kafka-topic PartitionCount:3 ReplicationFactor:3 Configs:
Topic: px-kafka-topic Partition: 0 Leader: 0 Replicas: 0,1,2 Isr: 0,2,1
Topic: px-kafka-topic Partition: 1 Leader: 1 Replicas: 1,2,0 Isr: 2,0,1
Topic: px-kafka-topic Partition: 2 Leader: 2 Replicas: 2,0,1 Isr: 2,0,1
Node Failover
In the case of a StatefulSet, a node may become unreachable under one of the following conditions:
- The node is down for maintenance
- There has been a network partition.
There is no way for Kubernetes to know which of the case is it. Hence Kubernetes would not schedule the Statefulset and the pods running on those nodes would enter the ‘Terminating’ or ‘Unknown’ state after a timeout. If there was a network partition and when the partition heals, Kubernetes will complete the deletion of the Pod and remove it from the API server. It would subsequently schedule a new pod to honor the replication requirements mentioned in the Podspec.
For further information : Statefulset Pod Deletion
Decommissioning a Kubernetes node deletes the node object form the APIServer. Before that you would want to decomission your Portworx node from the cluster. Follow the steps mentioned in Decommision a Portworx node Once done, delete the Kubernetes node if it requires to be deleted permanently.