主要用到split命令：可以将一个大文件分割成多个小文件，有时候文件太大了需要将文件分割成更小的片段，如数据库备份sql文件或者应用log
# 分切文件
这里举例分切一个423M的文件，将其分成若干个50m一个的小文件，分出来的文件默认aa,ab,ac..结尾
代码语言：javascript复制[root@summer test]# ll
total 432836
-rw-r--r-- 1 root root 443222812 Dec 14 09:33 tidb_install.zip
[root@summer test]# du -sh *
423M tidb_install.zip
[root@summer test]# cat tidb_install.zip | split -b 50m - ls_tidb_install.zip
[root@summer test]# ll
total 865672
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipaa
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipab
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipac
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipad
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipae
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipaf
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipag
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipah
-rw-r--r-- 1 root root 23792412 Dec 14 15:46 ls_tidb_install.zipai
-rw-r--r-- 1 root root 443222812 Dec 14 09:33 tidb_install.zip
[root@summer test]# du -sh *
50M ls_tidb_install.zipaa
50M ls_tidb_install.zipab
50M ls_tidb_install.zipac
50M ls_tidb_install.zipad
50M ls_tidb_install.zipae
50M ls_tidb_install.zipaf
50M ls_tidb_install.zipag
50M ls_tidb_install.zipah
23M ls_tidb_install.zipai
423M tidb_install.zip
[root@summer test]# mv ls_tidb_install.zipa* ../test2
[root@summer test]# cd ../test2
[root@summer test2]# du -sh *
50M ls_tidb_install.zipaa
50M ls_tidb_install.zipab
50M ls_tidb_install.zipac
50M ls_tidb_install.zipad
50M ls_tidb_install.zipae
50M ls_tidb_install.zipaf
50M ls_tidb_install.zipag
50M ls_tidb_install.zipah
23M ls_tidb_install.zipai# 合并文件
合并后的文件注意大小应和切割前的文件大小一致（可以看到这里都是423M）
代码语言：javascript复制[root@summer test2]# cat ls_tidb_install.zipa* > tidb_install.zip
[root@summer test2]# ll
total 865672
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipaa
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipab
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipac
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipad
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipae
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipaf
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipag
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipah
-rw-r--r-- 1 root root 23792412 Dec 14 15:46 ls_tidb_install.zipai
-rw-r--r-- 1 root root 443222812 Dec 14 15:50 tidb_install.zip
[root@summer test2]# du -sh *
50M ls_tidb_install.zipaa
50M ls_tidb_install.zipab
50M ls_tidb_install.zipac
50M ls_tidb_install.zipad
50M ls_tidb_install.zipae
50M ls_tidb_install.zipaf
50M ls_tidb_install.zipag
50M ls_tidb_install.zipah
23M ls_tidb_install.zipai
423M tidb_install.zip# 解压验证
代码语言：javascript复制[root@summer test2]# unzip tidb_install.zip
Archive: tidb_install.zip
creating: tidb_install/
inflating: tidb_install/install.sh
creating: tidb_install/include/
inflating: tidb_install/include/chk_install.sh
inflating: tidb_install/include/common.sh
inflating: tidb_install/include/Menu.sh
inflating: tidb_install/include/sysinfo.sh
inflating: tidb_install/include/tidb.sh
creating: tidb_install/src/
inflating: tidb_install/src/tidb-latest-linux-amd64.tar.gz
[root@summer test2]# ll
total 865672
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipaa
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipab
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipac
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipad
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipae
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipaf
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipag
-rw-r--r-- 1 root root 52428800 Dec 14 15:46 ls_tidb_install.zipah
-rw-r--r-- 1 root root 23792412 Dec 14 15:46 ls_tidb_install.zipai
drwxr-xr-x 4 root root 50 Jul 12 13:05 tidb_install
-rw-r--r-- 1 root root 443222812 Dec 14 15:50 tidb_install.zip
[root@summer test2]# 
