1. Create a new folder, such as/testmount/dev/sdb1/test.
2.cp -p /cognos/* /test Copy all files under /cognos to /test, which is your sdb 1, and keep all file attributes.
3.mv /cognos /cognos 1 You should name your folder, and don't delete it as a backup.
4. umount /test uninstalls sdb 1 mkdir /cognos to create a folder with the same permissions as the previous mount point, and ls -l has the same viewing permissions. Be sure to pay attention to the authority, otherwise it will be very sad. Chmod chown, these two commands are used to modify permissions and users, and they are reserved.
5. Try mount /dev/sdb 1 /cognos. Is everything all right with your application?
6.vim /etc/fatab adds a line.
/dev/sdb 1 /cognos ext3 default value 0 0
Stop working for a day