linux 根目录被沾满找不到原因,仿佛丢了4.7G

系统:SMP Wed Dec 19 10:46:58 EST 2018 x86_64 x86_64 x86_64 GNU/Linux

主机:3个node 的kvm虚拟机

系统收到告警,node-2 磁盘 / 目录的占用率98%,系统开始出现问题,于是把tranffic切到standby,ssh到node-2查看:

先执行了:df -h

[root@rmeda1-2 ~]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/vda2 9.8G 9.6G 240M 98% /

devtmpfs 15G 0 15G 0% /dev

tmpfs 15G 0 15G 0% /dev/shm

tmpfs 15G 129M 15G 1% /run

tmpfs 15G 0 15G 0% /sys/fs/cgroup

/dev/vdb2 57G 2.3G 55G 5% /var/cassandra/data

/dev/vdb1 9.4G 44M 9.3G 1% /var/cassandra/commitlog

/dev/vda1 997M 252M 746M 26% /boot

/dev/mapper/volgroup00-lv_home 15G 1.8G 13G 12% /home

/dev/mapper/volgroup00-lv_varlog 9.8G 3.0G 6.8G 31% /var/log

/dev/mapper/volgroup00-lv_tmp 2.0G 35M 2.0G 2% /tmp

tmpfs 3.0G 0 3.0G 0% /run/user/1001

tmpfs 3.0G 0 3.0G 0% /run/user/0

可以看出系统没有误报,确实根目录使用率达到了98%.

2. 切到根目录下查看,每个目录下的大小

[root@rmeda1-2 ~]#cd /

[root@rmeda1-2 /]#du -ah --max-depth=1

219M ./boot

0 ./dev

1.7G ./home

du: cannot access ‘./proc/20709/task/20709/fd/4’: No such file or directory