How to redirect docker logs with grep command to a text file?

Question

For finding specific logs from the docker logs, I am using the grep with docker logs as below

docker logs -f docker_container 2>&1 | grep "KafkaRecordGenerator:197"

Which is giving the correct result in the console. I need to redirect these logs to a text file. For that, I used the below command

docker logs -f docker_container 2>&1 | grep "KafkaRecordGenerator:197" >> test.txt

Here the new file test.txt is created but the output is not redirected to the test.txt file. How to redirect the docker logs with grep command to a text file?

Check out this answer https://stackoverflow.com/a/7162898/11344502 — anemyte, Apr 16 '21 at 13:45

score 2 · Accepted Answer · answered Apr 16 '21 at 13:53

2

As per the anemyte's comment, --line-buffered with grep command fixed my problem. The final command is,

docker logs -f docker_container 2>&1 | grep --line-buffered "KafkaRecordGenerator:197" >> test.txt

answered Apr 16 '21 at 13:53

Chintamani Manjare

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How to redirect docker logs with grep command to a text file?

1 Answers1