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kafkacat -b localhost:9092 \
         -t _kafka-connect-group-01-status \
         -C \
         -o-3 \
         -c3 \
         -f 'Topic %t / Partition %p / Offset: %o / Timestamp: %T\nHeaders: %h\nKey (%K bytes): %k\nPayload (%S bytes): %s\n--\n'

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Retrieving Docker Image Sizes

There are two metrics that are important to consider when discussing the size of Docker images.

1. Compressed size - This is often referred to as the wire size. This affects how fast/slow images can be pulled from a registry. This impacts the first run experience on machines where images are not cached.
2. Uncompressed size - This is often referred to as the size on disk. This affects how much local storage is required to support your Docker workloads.

The example commands shown below will work on Windows, MacOS, and Linux.

How to Measure the Compressed Size

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# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software

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Producer

Setup
bin/kafka-topics.sh --zookeeper esv4-hcl197.grid.linkedin.com:2181 --create --topic test-rep-one --partitions 6 --replication-factor 1
bin/kafka-topics.sh --zookeeper esv4-hcl197.grid.linkedin.com:2181 --create --topic test --partitions 6 --replication-factor 3

Single thread, no replication

bin/kafka-run-class.sh org.apache.kafka.clients.tools.ProducerPerformance test7 50000000 100 -1 acks=1 bootstrap.servers=esv4-hcl198.grid.linkedin.com:9092 buffer.memory=67108864 batch.size=8196

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#Required Python packages
#pip3 install msal

import json
import msal
import random
import requests
import string
import sys
import time

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1. Add a sidecar container:
cat <<EOF > patch-file.yaml
spec:
  template:
    spec:
      shareProcessNamespace: true
      securityContext:
        runAsUser: 0
        fsGroup: 0
      volumes:

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scaled down the statefulset, backed up the PVC definition, removed it, scaled back up and the pod came back.

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for ns in $(kubectl get k -A --no-headers | cut -d' ' -f1)
do
  printf "namespace=$ns\n"
  kubectl patch -n "$ns" kt $(kubectl get kt -n "$ns" -o custom-columns=TOPIC_NAME:.metadata.name | grep strimzi-topic-operator | head -n 1) -p '{"spec": {"config": {"min.insync.replicas": 1}}}' --type=merge
  printf "\n"
done

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cat <<EOF > /tmp/open.sh
open service:jmx:rmi:///jndi/rmi://127.0.0.1:9999/jmxrmi
beans
EOF

curl -L https://github.com/jiaqi/jmxterm/releases/download/v1.0.2/jmxterm-1.0.2-uber.jar -o /tmp/jmxterm.jar

java -jar /tmp/jmxterm.jar -i /tmp/open.sh

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# Testing process to expand k8s PVCs without losing data

#region Install
# Check the current cluster
kubectl config current-context

# Add bitnami repo
helm repo list
helm repo add bitnami https://charts.bitnami.com/bitnami