If you hit this error trying to format a partition after you have installed a new disk in your server:
~# mkfs -t xfs -f -i size=2048 /dev/sdav2 mkfs.xfs: cannot open /dev/sdav2: Device or resource busy
Maybe you have multipath enabled and the new device has been detected. Run this command to see if multipath has detected it.
~# multipath -ll /dev/sdav 2796a30585a4b6e45 dm-12 , size=2.2T features='0' hwhandler='0' wp=rw |-+- policy='service-time 0' prio=0 status=active | `- #:#:#:# sdav 66:48 active undef running
then to fix it, remove from multipath:
~# multipath -f /dev/sdav
And finally you can format it without any problem:
~# mkfs -t xfs -f -i size=2048 /dev/sdav2
meta-data=/dev/device isize=2048 agcount=4, agsize=3277258 blks
= sectsz=512 attr=2
data = bsize=4096 blocks=13109032, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0
log =internal log bsize=4096 blocks=6400, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0