1.可以通过清除系统日志来清理空间，输入以下命令即可清理对应文件

cat /dev/null > /var/log/syslog

cat /dev/null > /var/adm/sylog

cat /dev/null > /var/log/wtmp

cat /dev/null > /var/log/maillog

cat /dev/null > /var/log/messages

cat /dev/null > /var/log/openwebmail.log

cat /dev/null > /var/log/maillog

cat /dev/null > /var/log/secure

cat /dev/null > /var/log/httpd/error_log

cat /dev/null > /var/log/httpd/ssl_error_log

cat /dev/null > /var/log/httpd/ssl_request_log

cat /dev/null > /var/log/httpd/ssl_access_log