在Ubuntu系统下安装sar出错，信息为：Please check if data collecting is enabled in /etc/default/sysstat
1、安装sysstat
apt-get install sysstat
2、安装后无法使用：
Cannot open /var/log/sysstat/sa02: No such file or directory
Please check if data collecting is enabled in /etc/default/sysstat
3、修改配置文件：vi /etc/default/sysstat
将False改为True
----
# Should sadc collect system activity informations? Valid values
# are "true" and "false". Please do not put other values, they
# will be overwritten by debconf!
ENABLED="true"
----
4、重启sysstat服务即可
service sysstat restart