Found a swap file by the name ".server.xml.swp"
owned by: root dated: Thu Oct 26 09:15:39 2017
file name: /data/tomcat-server/conf/server.xml
While opening file "server.xml"
dated: Mon Nov 6 11:20:47 2017
NEWER than swap file!
(1) Another program may be editing the same file. If this is the case,
be careful not to end up with two different instances of the same
file when making changes. Quit, or continue with caution.
(2) An edit session for this file crashed.
If you did this already, delete the swap file ".server.xml.swp"
to avoid this message.
Swap file ".server.xml.swp" already exists!
[O]pen Read-Only, (E)dit anyway, (R)ecover, (D)elete it, (Q)uit, (A)bort:
解決方案：ls -a 查看隱藏文件，在linux系統中 隱藏文件以點開頭，如果發現類型 .server.xml.swp 的文件！直接刪除就可以了