root@debian:~# update-alternatives --config editor
There are 8 choices for the alternative editor (providing /usr/bin/editor).
Selection Path Priority Status
------------------------------------------------------------
0 /usr/bin/joe 70 auto mode
* 1 /bin/nano 40 manual mode
2 /usr/bin/jmacs 50 manual mode
3 /usr/bin/joe 70 manual mode
4 /usr/bin/jpico 50 manual mode
5 /usr/bin/jstar 50 manual mode
6 /usr/bin/rjoe 25 manual mode
7 /usr/bin/vim.basic 30 manual mode
8 /usr/bin/vim.tiny 10 manual mode
Press enter to keep the current choice[*], or type selection number: 8
update-alternatives: using /usr/bin/vim.tiny to provide /usr/bin/editor (editor) in manual mode.
输入命令之后，提示选择，根据自己喜好进行选择即可，这里我选择的是VI编辑器，输入8。
现在crontab编辑器已经变成了VI。
如果没有切换成功，请手动重启一下服务：/etc/init.d/cron restart
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