I got the worry message in the midnight, about the web server is down.
When I login, the server shows man directories can not mount as read and write.
Directory can not write has happened before, when the disk is full.
But can not mount disk as rewrite is not the disk full issue.
It’s not work when I clean these large log.
And I also check the disk free space with df -l command.
It’s fail after system snapshot.
when I roll back to the snapshot then boot up system.
System is work.
I think this issue may cause by snapshot tool.
And I also modify the nginx log rotate setting.
It might help me to issue out the root cause easily.