---
id: 2b7f490f-0596-439d-a19e-506f8d99db3e
---

# Kafka Message Deserialization Errors Incident.
---

This incident type involves errors that occur during the process of converting serialized data received by the Kafka message queue into a usable format. Deserialization errors can happen for various reasons, such as incorrect data types or missing fields in the serialized data. These errors can cause issues with the application's functionality and can lead to service disruptions or outages. Troubleshooting and resolving these errors can require a deep understanding of the application's code and the data being processed.

### Parameters
```shell
export KAFKA_LOG_FILE="PLACEHOLDER"

export TOPIC_NAME="PLACEHOLDER"

export ZOOKEEPER_HOST="PLACEHOLDER"

export ZOOKEEPER_PORT="PLACEHOLDER"

export VERSION_NUMBER="PLACEHOLDER"

export SUBJECT_NAME="PLACEHOLDER"

export BROKER_HOST="PLACEHOLDER"

export BROKER_PORT="PLACEHOLDER"


```

## Debug

### Find the most recent log file for the Kafka broker
```shell
ls -t /var/log/kafka/kafka.log.* | head -1
```

### Filter the log file for deserialization errors
```shell
grep "Error deserializing key/value" ${KAFKA_LOG_FILE}
```

### Check the topic configuration for message encoding
```shell
kafka-configs.sh --describe --zookeeper ${ZOOKEEPER_HOST}:${ZOOKEEPER_PORT} --entity-type topics --entity-name ${TOPIC_NAME}
```

### Check the message schema for compatibility issues
```shell
kafka-schema-registry.sh --compatibility --subject ${SUBJECT_NAME} --version ${VERSION_NUMBER}
```

### View the raw bytes of a message
```shell
kafka-console-consumer.sh --bootstrap-server ${BROKER_HOST}:${BROKER_PORT} --topic ${TOPIC_NAME} --from-beginning --formatter "kafka.tools.DefaultMessageFormatter" --property print.key=true --property print.value=true --max-messages 1
```

## Repair

### Consider scaling up the resources allocated to the Kafka message queue, such as increasing the number of partitions or brokers, to handle the increased load.
```shell


#!/bin/bash



# Set variables

${NUM_PARTITIONS}

${NUM_BROKERS}



# Stop Kafka service

sudo systemctl stop kafka



# Update Kafka configuration file with new partition and broker values

sudo sed -i "s/^num.partitions=.*/num.partitions=$NUM_PARTITIONS/" /path/to/server.properties

sudo sed -i "s/^num.brokers=.*/num.brokers=$NUM_BROKERS/" /path/to/server.properties



# Start Kafka service

sudo systemctl start kafka


```

This incident type involves errors that occur during the process of converting serialized data received by the Kafka message queue into a usable format. Deserialization errors can happen for various reasons, such as incorrect data types or missing fields in the serialized data. These errors can cause issues with the application's functionality and can lead to service disruptions or outages. Troubleshooting and resolving these errors can require a deep understanding of the application's code and the data being processed.


```shell
export KAFKA_LOG_FILE="PLACEHOLDER"

export TOPIC_NAME="PLACEHOLDER"

export ZOOKEEPER_HOST="PLACEHOLDER"

export ZOOKEEPER_PORT="PLACEHOLDER"

export VERSION_NUMBER="PLACEHOLDER"

export SUBJECT_NAME="PLACEHOLDER"

export BROKER_HOST="PLACEHOLDER"

export BROKER_PORT="PLACEHOLDER"


```


### Find the most recent log file for the Kafka broker

```shell
ls -t /var/log/kafka/kafka.log.* | head -1
```

### Filter the log file for deserialization errors

```shell
grep "Error deserializing key/value" ${KAFKA_LOG_FILE}
```

### Check the topic configuration for message encoding

```shell
kafka-configs.sh --describe --zookeeper ${ZOOKEEPER_HOST}:${ZOOKEEPER_PORT} --entity-type topics --entity-name ${TOPIC_NAME}
```

### Check the message schema for compatibility issues

```shell
kafka-schema-registry.sh --compatibility --subject ${SUBJECT_NAME} --version ${VERSION_NUMBER}
```

### View the raw bytes of a message

```shell
kafka-console-consumer.sh --bootstrap-server ${BROKER_HOST}:${BROKER_PORT} --topic ${TOPIC_NAME} --from-beginning --formatter "kafka.tools.DefaultMessageFormatter" --property print.key=true --property print.value=true --max-messages 1
```


### Consider scaling up the resources allocated to the Kafka message queue, such as increasing the number of partitions or brokers, to handle the increased load.

```shell


#!/bin/bash



# Set variables

${NUM_PARTITIONS}

${NUM_BROKERS}



# Stop Kafka service

sudo systemctl stop kafka



# Update Kafka configuration file with new partition and broker values

sudo sed -i "s/^num.partitions=.*/num.partitions=$NUM_PARTITIONS/" /path/to/server.properties

sudo sed -i "s/^num.brokers=.*/num.brokers=$NUM_BROKERS/" /path/to/server.properties



# Start Kafka service

sudo systemctl start kafka


```


Kafka Message Deserialization Errors Incident.

Overview

Parameters

Debug

Find the most recent log file for the Kafka broker

Filter the log file for deserialization errors

Check the topic configuration for message encoding

Check the message schema for compatibility issues

View the raw bytes of a message

Repair

Consider scaling up the resources allocated to the Kafka message queue, such as increasing the number of partitions or brokers, to handle the increased load.

Learn more

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