losetup

Mir sind solche Mounts immer mal wieder untergekommen:

servername:~ # umount /some/nfspath
umount.nfs: /some/nfspath: device is busy
umount.nfs: /some/nfspath: device is busy
servername:~ # losetup -a | grep /some/nfspath
loop: can't get info on device /dev/loop21: Stale NFS file handle
/dev/loop41: [001a]:14119 (/some/nfspath/loopback-blockdevice)
servername:~ # losetup -d /dev/loop41
loop: can't delete device /dev/loop41: Device or resource busy
servername:~ # 

Und nun? Die Lösung lag darin, zuerst die zugehörige Partition loszuwerden:

servername:~ # dmsetup table | grep loop41
loop41p1: 0 314566656 linear 7:41 2048
servername:~ # dmsetup remove loop41p1
servername:~ # losetup -d /dev/loop41
servername:~ # umount /some/nfspath
servername:~ #