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伺服器日誌顯示，半分鐘報一次錯誤：

Mar 29, 2016 10:37:23 AM java.util.prefs.FileSystemPreferences checkLockFile0ErrorCode WARNING: Could not lock User prefs.  Unix error code 2. Mar 29, 2016 10:37:23 AM java.util.prefs.FileSystemPreferences checkLockFile0ErrorCode WARNING: Could not lock User prefs.  Unix error code 2. Mar 29, 2016 10:37:23 AM java.util.prefs.FileSystemPreferences syncWorld WARNING: Couldn't flush user prefs: java.util.prefs.BackingStoreException: Couldn't get file lock. Mar 29, 2016 10:37:23 AM java.util.prefs.FileSystemPreferences syncWorld WARNING: Couldn't flush user prefs: java.util.prefs.BackingStoreException: Couldn't get file lock. Mar 29, 2016 10:37:25 AM java.util.prefs.FileSystemPreferences checkLockFile0ErrorCode WARNING: Could not lock System prefs. Unix error code 0. Mar 29, 2016 10:37:25 AM java.util.prefs.FileSystemPreferences checkLockFile0ErrorCode WARNING: Could not lock System prefs. Unix error code 0. Mar 29, 2016 10:37:25 AM java.util.prefs.FileSystemPreferences syncWorld WARNING: Couldn't flush system prefs: java.util.prefs.BackingStoreException: Couldn't get file lock. Mar 29, 2016 10:37:25 AM java.util.prefs.FileSystemPreferences syncWorld WARNING: Couldn't flush system prefs: java.util.prefs.BackingStoreException: Couldn't get file lock. 本來無傷大雅，但是把日誌都給我頂沒了讓我很惆悵，於是決定解決掉他，多方查詢，發現造成這個問題的原因是jdk去鎖定使用者配置的時候無法鎖定，其實就是各種許可權問題，好多文章說去掉/etc/.java就可以了 我試了試 不行 看了如下兩篇文章 http://www.ithao123.cn/content-10680341.html http://www-01.ibm.com/support/docview.wss?uid=swg21515420 得到了一些啟發 然後我發現需要給tomcat的登入使用者賦值/etc/.java的操作許可權，由於是自帶的tomcat6，我開啟tomcat6.conf檔案後發現這麼一行: TOMCAT_USER="tomcat" 出於偷懶，果斷改成root，至此，問題解決 下面才是重點
但是畢竟讓tomcat拿到root許可權不是什麼安全的事情，如果日後集團安全檢查，一定會掃出漏洞，所以把tomcat使用者的許可權都賦值： # chown tomcat:tomcat -R /etc/.java/.systemPrefs # chown tomcat:tomcat -R /etc/.java # chown tomcat:tomcat -R /var/lock/subsys/tomcat6 # chown tomcat:tomcat -R /var/log/tomcat6 # chown tomcat:tomcat -R /var/lib/tomcat6 # chown tomcat:tomcat -R /var/cache/tomcat6 # chown tomcat:tomcat -R /etc/rc.d/init.d/tomcat6 # chown tomcat:tomcat -R /etc/logrotate.d/tomcat6 # chown tomcat:tomcat -R /etc/sysconfig/tomcat6 # chown tomcat:tomcat -R /etc/tomcat6 # chown tomcat:tomcat -R /usr/sbin/tomcat6 # chown tomcat:tomcat -R /usr/share/tomcat6 # chown tomcat:tomcat -R /usr/share/java/tomcat6 再把tomcat登入使用者改回tomcat，重啟，果然依舊沒有問題