Hi!
Check whether the disk capacity is full.
You can use the command df –h. If the disk is full, check the specific cause.If the fault persists, go to the next step.
You can use the command df –i to check the disk inode.
If /var usage is 100% and is found that '/var/spool/postfix/maildrop' is used too much, it might be you. In the system, that enables the cron function.
The program executed by the cron process has output content and the output content is sent to the cron user via email.
However, the sendmail file is not started, so the system creates many 'maildrop' files.
You can:
1. Clear the 'maildrop' files;
2. Edit the /etc/crontab file; make the ouput connect to '/dev/null'.