[Linux command] Linux checks the log of a certain time period (sed -n)

Posted by chandler on Mon, 22 Nov 2021 20:32:34 +0100

preface

When searching for logs on linux, if I want to find logs for a certain period of time, such as looking for logs from 8 a.m. to 2 p.m. this morning.
It's not convenient to filter it directly with grep. You can use sed to find it according to time

sed -n '/ start time date /, / end time date / p' all.log

Find log

For example, the time formats of the following logs are similar   2019-10-21 07:44:20

2019-10-24 21:33:31,678 [django.request:93] [base:get_response] [WARNING]- Not Found: /http:/123.125.114.144/
2019-10-24 21:33:31,679 [django.server:124] [basehttp:log_message] [WARNING]- "HEAD http://123.125.114.144/ HTTP/1.1" 404 1678
2019-10-24 22:14:04,121 [django.server:124] [basehttp:log_message] [INFO]- code 400, message Bad request version ('HTTP')
2019-10-24 22:14:04,122 [django.server:124] [basehttp:log_message] [WARNING]- "GET ../../mnt/custom/ProductDefinition HTTP" 400 -
2019-10-24 22:16:21,052 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/login HTTP/1.1" 301 0
2019-10-24 22:16:21,123 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/login/ HTTP/1.1" 200 3876
2019-10-24 22:16:21,192 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/img/main_bg.png HTTP/1.1" 200 2801
2019-10-24 22:16:21,196 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/iconfont/style.css HTTP/1.1" 200 1638
2019-10-24 22:16:21,229 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/img/bg.jpg HTTP/1.1" 200 135990
2019-10-24 22:16:21,307 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/iconfont/fonts/icomoon.ttf?u4m6fy HTTP/1.1" 200 6900
2019-10-24 22:16:23,525 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/login/ HTTP/1.1" 302 0
2019-10-24 22:16:23,618 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/index/ HTTP/1.1" 200 18447
2019-10-24 22:16:23,709 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/js/commons.js HTTP/1.1" 200 13209
2019-10-24 22:16:23,712 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/css/admin.css HTTP/1.1" 200 19660
2019-10-24 22:16:23,712 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/css/common.css HTTP/1.1" 200 1004
2019-10-24 22:16:23,714 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/js/app.js HTTP/1.1" 200 20844
2019-10-24 22:16:26,509 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/report_list/1/ HTTP/1.1" 200 14649
2019-10-24 22:16:51,496 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/test_list/1/ HTTP/1.1" 200 24874
2019-10-24 22:16:51,721 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/add_case/ HTTP/1.1" 200 0
2019-10-24 22:16:59,707 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/test_list/1/ HTTP/1.1" 200 24874
2019-10-24 22:16:59,909 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/add_case/ HTTP/1.1" 200 0
2019-10-24 22:17:01,306 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/edit_case/1/ HTTP/1.1" 200 36504
2019-10-24 22:17:06,265 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/add_project/ HTTP/1.1" 200 17737
2019-10-24 22:17:07,825 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/project_list/1/ HTTP/1.1" 200 29789
2019-10-24 22:17:13,116 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/add_config/ HTTP/1.1" 200 24816
2019-10-24 22:17:19,671 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/config_list/1/ HTTP/1.1" 200 19532 

For example, I want to find the above from   2019-10-24 22:16:21   reach   2019-10-24 22:16:59   Log for this time period

sed -n '/2019-10-24 22:16:21/,/2019-10-24 22:16:59/p' all.log

[root@VM_0_2_centos logs]# sed -n  '/2019-10-24 22:16:21/,/2019-10-24 22:16:59/p' all.log
2019-10-24 22:16:21,052 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/login HTTP/1.1" 301 0
2019-10-24 22:16:21,123 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/login/ HTTP/1.1" 200 3876
2019-10-24 22:16:21,192 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/img/main_bg.png HTTP/1.1" 200 2801
2019-10-24 22:16:21,196 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/iconfont/style.css HTTP/1.1" 200 1638
2019-10-24 22:16:21,229 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/img/bg.jpg HTTP/1.1" 200 135990
2019-10-24 22:16:21,307 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/iconfont/fonts/icomoon.ttf?u4m6fy HTTP/1.1" 200 6900
2019-10-24 22:16:23,525 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/login/ HTTP/1.1" 302 0
2019-10-24 22:16:23,618 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/index/ HTTP/1.1" 200 18447
2019-10-24 22:16:23,709 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/js/commons.js HTTP/1.1" 200 13209
2019-10-24 22:16:23,712 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/css/admin.css HTTP/1.1" 200 19660
2019-10-24 22:16:23,712 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/css/common.css HTTP/1.1" 200 1004
2019-10-24 22:16:23,714 [django.server:124] [basehttp:log_message] [INFO]- "GET /static/assets/js/app.js HTTP/1.1" 200 20844
2019-10-24 22:16:26,509 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/report_list/1/ HTTP/1.1" 200 14649
2019-10-24 22:16:51,496 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/test_list/1/ HTTP/1.1" 200 24874
2019-10-24 22:16:51,721 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/add_case/ HTTP/1.1" 200 0
2019-10-24 22:16:59,707 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/test_list/1/ HTTP/1.1" 200 24874
[root@VM_0_2_centos logs]# 

It seems that the use is very simple, but there will be a big hole. For example, the / p after the time cannot be omitted

Pit encountered

The start time and end time must be in the log. If there is no time, the search will have no results. I have also been cheated. This is the sentence in the online tutorials, but some people in the comments always say that it was unsuccessful.
Later, after practice, there is no problem with the instruction, but the start time and end time must be in the log.

If there is no start time in the log, the query result is empty. For example, there is no start time at 22:16:22 on October 24, 2019

sed -n '/2019-10-24 22:16:22/,/2019-10-24 22:16:59/p' all.log

If there is no end time in the log, the query result is all logs from the start time to the last

sed -n '/2019-10-24 22:16:21/,/2019-10-24 22:16:58/p' all.log

Fuzzy query

If you don't know the start time of the log and can't be accurate to seconds, you can use fuzzy query, such as the query time period from 22:14 to 22:16 of 2019-10-24

sed -n '/2019-10-24 22:14:/,/2019-10-24 22:16:/p' all.log

[root@VM_0_2_centos logs]# sed -n  '/2019-10-24 22:14:*/,/2019-10-24 22:16:*/p' all.log
2019-10-24 22:14:04,121 [django.server:124] [basehttp:log_message] [INFO]- code 400, message Bad request version ('HTTP')
2019-10-24 22:14:04,122 [django.server:124] [basehttp:log_message] [WARNING]- "GET ../../mnt/custom/ProductDefinition HTTP" 400 -
2019-10-24 22:16:21,052 [django.server:124] [basehttp:log_message] [INFO]- "GET /api/login HTTP/1.1" 301 0
[root@VM_0_2_centos logs]# 

You can also fuzzy query by hour

sed -n '/2019-10-24 21/,/2019-10-24 22/p' all.log

Combined with grep query

sed can also be used in combination with grep. For example, I can query the information with a certain time period in the above log   POST   Log lines for

sed -n '/2019-10-24 22:16:21/,/2019-10-21 20:16:58/p' all.log | grep POST

[root@VM_0_2_centos logs]# sed -n  '/2019-10-24 22:16:21/,/2019-10-21 20:16:58/p' all.log | grep post
[root@VM_0_2_centos logs]# sed -n  '/2019-10-24 22:16:21/,/2019-10-21 20:16:58/p' all.log | grep POST
2019-10-24 22:16:23,525 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/login/ HTTP/1.1" 302 0
2019-10-24 22:16:51,721 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/add_case/ HTTP/1.1" 200 0
2019-10-24 22:16:59,909 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/add_case/ HTTP/1.1" 200 0
2019-10-24 22:17:19,864 [django.server:124] [basehttp:log_message] [INFO]- "POST /api/add_case/ HTTP/1.1" 200 0
[root@VM_0_2_centos logs]# 

Log export

We can query the logs of a certain period of time and export them to the local database

sed -n '/2019-10-24 22:16:21/,/2019-10-21 20:16:58/p' all.log > yoyo.log

[root@VM_0_2_centos logs]# sed -n  '/2019-10-24 22:16:21/,/2019-10-21 20:16:58/p' all.log > yoyo.log
[root@VM_0_2_centos logs]# ll
total 1740
-rw-r--r-- 1 root root    1907 Oct 24 22:54 11.txt
-rw-r--r-- 1 root root 1081515 Oct 24 23:04 all.log
-rw-r--r-- 1 root root  686962 Oct 24 23:04 script.log
-rw-r--r-- 1 root root    3053 Oct 24 23:08 yoyo.log
[root@VM_0_2_centos logs]# 

Topics: Linux