System Tutorial
LINUX
There are a lot of logs in the Linux server. How to read the logs correctly and quickly locate errors? You must learn!
There are a lot of logs in the Linux server. How to read the logs correctly and quickly locate errors? You must learn!
Quickly locate errors in a large number of logs
Dynamic View Log
tail -f catalina.ou
Open the log file from the beginning
cat catalina.ou
You can use >nanjiangtest.txt to output a new log to view
[root@yesky logs]# cat -n catalina.out |grep 717892466 >nanjiangtest.txt
tail/head simple command usage:
[root@yesky logs]# tail -n number catalina.out 查询日志尾部最后number行的日志 [root@yesky logs]# tail -n +number catalina.out 查询number行之后的所有日志 [root@yesky logs]# head -n number catalina.out 查询日志文件中的前number行日志 [root@yesky logs]# head -n -number catalina.out 查询日志文件除了最后number行的其他所有日志
The first way (find the trip number based on keywords):
There are very few logs obtained with grep, we need to check nearby logs. This is what I did, first: cat -n test.log | grep "keyword" Get the line number of the key log
[root@yesky logs]# cat -n catalina.out |grep 717892466 13230539 [11:07 17:47:11] INFO nanjiang:Edit Old Article：717892466-2020-11- 07 17:47:11 13230593 [11:07 17:47:15] INFO nanjiangSave Article ID IS：717892466 13230595 717892466 article.getDisplayTime()1 = 2020-11-07 16:25:11 13230596 717892466 article.getDisplayTime()2 = 2020-11-07 16:25:11 13230601 [11:07 17:47:15] INFO 南江 10.10.10.39 edit article 717892466 编辑 文章
「cat -n catalina.out|tail -n 13230539|head -n 10」
-
tail -n 13230539means querying the log after line 13230539 -
head -n 10means to check the first 10 records in the previous query results
[root@yesky logs]# cat -n catalina.out |tail -n +13230539|head -n 10 13230539 [11:07 17:47:11] INFO nanjiang:Edit Old Article：717892466- 2020-11-07 17:47:11 13230540 [11:07 17:47:11] INFO Takes:2 ms class com.tmg.cms.manager. dao.article.impl.ArticleContentDaoImpl getListByArticleId [NzE3ODkyNDY2] [int] 13230541 [11:07 17:47:11] INFO Takes:1 ms class com.tmg.cms.manager. dao.resourceImage.impl.ResourceImageDaoImpl load 13230542 [11:07 17:47:11] INFO Takes:0 ms class com.tmg.cms.manager. dao.resourceImage.impl.ResourceImageDaoImpl load 13230543 [11:07 17:47:11] INFO Takes:1 ms class com.tmg.cms.manager. dao.resourceImage.impl.ResourceImageDaoImpl load 13230544 [11:07 17:47:11] INFO article.getImage3：/uploadImages/2020/ 312/02/3NXCRK4U3589_2.jpg 13230545 [11:07 17:47:11] INFO Takes:0 ms class com.tmg.cms.manager. dao.resourceImage.impl.ResourceImageDaoImpl load 13230546 [11:07 17:47:11] INFO Takes:2 ms class com.tmg.cms.manager. dao.privilege.impl.UserDaoImpl getUserByid 13230547 [11:07 17:47:11] INFO Takes:57 ms class com.tmg.cms.manager .dao.sitemap.impl.SitemapDaoImpl selectSitemapWithoutAudit [MQ==] [int] 13230548 [11:07 17:47:11] INFO Takes:5 ms class com.tmg.cms.manager .dao.forbidword.impl.ForbidwordDaoImpl getForbidwordBysiteid [MjI=] [int]
Second method: View logs within a specified time period
First, perform a log query within the range time period to see if it exists within the current day.
grep '11:07 18:29:20' catalina.out grep '11:07 18:31:11' catalina.out
Query within time range
sed -n '/11:07 18:29:20/,/11:07 18:31:11/p' catalina.out sed -n '/11:07 18:29:/,/11:07 18:31:/p' catalina.out
第三种方式：查看日志中特定字符的匹配数目
[root@yesky logs]# grep '1175109632' catalina.out | wc -l 154
第四种方式：查询最后number行，并查找关键字“结果”
[root@yesky logs]# tail -n 20 catalina.out | grep 'INFO Takes:1' [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.config.impl.ConfigInfoDaoImpl load [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTkwOTQ5] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzI0] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzI3] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzMw] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzA5NA==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [Mzc4Mg==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [OTM1MA==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MTE5MDMw] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTQ2MzQw] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTg2NzYy] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzYyMjA=] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.configModule.impl.ConfigModuleDaoImpl getPersonMenuList
第五种方式：查询最后number行，并查找关键字“结果”并且对结果进行标红
[root@yesky logs]# tail -n 20 catalina.out | grep 'INFO Takes:1' --color [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.config.impl.ConfigInfoDaoImpl load [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTkwOTQ5] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzI0] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzI3] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzMw] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzA5NA==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [Mzc4Mg==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [OTM1MA==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MTE5MDMw] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTQ2MzQw] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTg2NzYy] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzYyMjA=] [int]
第六种方式：查询最后number行，并查找关键字“结果”并且对结果进行标红，上下扩展两行
[root@yesky logs]# tail -n 20 catalina.out | grep 'INFO Takes:1' --color -a2 [11:11 22:02:51] INFO Takes:0 ms class com.tmg.cms.manager.dao.article.impl.ArticleContent DaoImpl getArticlePageNum [NzE4MTM2ODky] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.config.impl.ConfigInfoDaoImpl load [com.tmg.cms.manager.model.config.ConfigInfo] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTkwOTQ5] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzI0] [int] [11:11 22:02:51] INFO Takes:0 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzI1] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzI3] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzMw] [int] [11:11 22:02:51] INFO Takes:0 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzAzNg==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzA5NA==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [Mzc4Mg==] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [OTM1MA==] [int] [11:11 22:02:51] INFO Takes:0 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MTE0MjQ4] [int] [11:11 22:02:51] INFO Takes:0 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MTE4MDc4] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MTE5MDMw] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTQ2MzQw] [int] [11:11 22:02:51] INFO Takes:0 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTQ3MTIw] [int] [11:11 22:02:51] INFO Takes:0 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTY4OTYx] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [NTg2NzYy] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.sitemap.impl.SitemapDaoImpl getSitemapTop [MzYyMjA=] [int] [11:11 22:02:51] INFO Takes:1 ms class com.tmg.cms.manager.dao.configModule.impl.ConfigModuleDaoImpl getPersonMenuList [com.tmg.cms.manager.model.config.ConfigPersonMenu]
第七种方式：分页查看，使用空格翻页(使用more/less)
[root@yesky logs]# tail -n 2000 catalina.out | grep 'INFO Takes:1' --color -a2 | more [root@yesky logs]# tail -n 2000 catalina.out | grep 'INFO Takes:1' --color -a2 | less
附加
1.全屏导航
-
ctrl + F– 向前移动一屏 -
ctrl + B– 向后移动一屏 -
ctrl + D– 向前移动半屏 -
ctrl + U– 向后移动半屏
2.单行导航
-
j– 向前移动一行 -
k– 向后移动一行
3.其它导航
-
G– 移动到最后一行 -
g– 移动到第一行 -
q / ZZ– 退出 less 命令
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