Unable To Umount

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on an EL5 XEN DOM0 system I have following volume

$ df -h /srv Filesystem Size Used Avail Use% Mounted on
/dev/sdc1 917G 858G 60G 94% /srv

that partition was used by virtual machines but they were all halted.

service xendomains stop

$ xm list Name ID Mem(MiB) VCPUs State Time(s)
Domain-0 0 3000 2 r—– 695.1

$ service xend stop

nothing is using the partition
$ lsof |grep srv

$ fuser -m /srv

$ fuser -km /srv

but i can not umount /srv

$ umount /srv umount: /srv: device is busy umount: /srv: device is busy

what could keeping the device “busy” … ?



4 thoughts on - Unable To Umount

  • Run as root:
    # lsof +D /srv

    Again, run this as root. Compare (test example from my system):
    $ fuser -m /boot 2>/dev/null | wc
    0 44 264
    # fuser -m /boot 2>/dev/null | wc
    0 223 1338

    That’s 180 processes I’d miss as an ordinary user.

    I’m sure you’ve checked, but where is your PWD?


  • Although the prompt is a $, I assume you’re actually doing this as root?

    Is the device NFS exported? I’ve seem that prevent umounting even though nothing shows up in the process list.