Setting quota on XFS root filesystem fails with error "setquota: No correct mountpoint specified"

• While configuring quota on a root filesystem which is formatted with XFS, following error is observed

server:~ # setquota -u user1 5000 8000 0 0 /dev/sda4
setquota: Cannot find mountpoint for device /dev/sda4
setquota: No correct mountpoint specified.
setquota: Cannot initialize mountpoint scan.

• The entry in /etc/fstab file is already configured to enable quota, however in the mount options we still see noquota being used

server:~ # cat /etc/fstab | grep ' / '
UUID=c3c2cc2a-84f7-4495-9816-f8e2df8155e0  /             xfs   defaults,usrquota,grpquota  0  1

server:~ # cat /proc/mounts | grep ' / '
/dev/sda4 / xfs rw,relatime,attr2,inode64,logbufs=8,logbsize=32k,noquota 0 0

• xfs_quota command also confirms the same 

server:~ #  xfs_quota -x -c 'state -v' /
User quota are not enabled on /dev/sda4
Group quota are not enabled on /dev/sda4
Project quota are not enabled on /dev/sda4

• For XFS root filesystem, quota needs to be enabled with the boot parameter "rootflags="
• Edit the file /etc/default/grub by adding "rootflags=" parameter to the line starting with GRUB_CMDLINE_LINUX_DEFAULT

GRUB_CMDLINE_LINUX_DEFAULT="boot=/dev/sda3 USE_BY_UUID_DEVICE_NAMES=1 earlyprintk=ttyS0 console=ttyS0 rootdelay=300 net.ifnames=0 dis_ucode_ldr scsi_mod.use_blk_mq=1 multipath=off rootflags=uquota,gquota,pquota"

• If not done already, check the status of quotaon service. It should be active. 

server:~ # systemctl status quotaon.service

• It is always a good idea to create a backup of grub.cfg file, before generating a new grub2 configuration file

server:~ # cp /boot/grub2/grub.cfg /boot/grub2/grub.cfg.bkp 

• Generate a new grub2 configuration file and reboot the server

server:~ # grub2-mkconfig -o /boot/grub2/grub.cfg
server:~ # systemctl reboot

• After rebooting, ensure that usrquota, grpquota (and/or prjquota) mount options are visible for root filesystem

server:~ # cat /proc/mounts | grep ' / '
/dev/sda4 / xfs rw,relatime,attr2,inode64,logbufs=8,logbsize=32k,usrquota,prjquota,grpquota 0 0

• Now, running xfs_quota command will report default values which can be modified by setting user, group or project quota either through command line or by using YaST

server:~ # xfs_quota -x -c 'state -v' /
User quota state on / (/dev/sda4)
  Accounting: ON
  Enforcement: ON
  Inode: #1088896 (6 blocks, 6 extents)
Blocks grace time: [7 days]
Blocks max warnings: 5
Inodes grace time: [7 days]
Inodes max warnings: 5
Realtime Blocks grace time: [7 days]
Group quota state on / (/dev/sda4)
  Accounting: ON
  Enforcement: ON
  Inode: #1088897 (7 blocks, 5 extents)
Blocks grace time: [7 days]
Blocks max warnings: 5
Inodes grace time: [7 days]
Inodes max warnings: 5
Realtime Blocks grace time: [7 days]
Project quota state on / (/dev/sda4)
  Accounting: ON
  Enforcement: ON
  Inode: #1088898 (1 blocks, 1 extents)
Blocks grace time: [7 days]
Blocks max warnings: 5
Inodes grace time: [7 days]
Inodes max warnings: 5
Realtime Blocks grace time: [7 days]

• For root filesystems formatted with type XFS, the default kernel mount option used is noquota. This is why setquota command or YaST fails to enable any type of quota for this filesystem. 
• From the man page of xfs_quota:

• For detailed procedure on how to set quota using YaST, kindly refer to the following documents:

1. SLES 12 : https://documentation.suse.com/sles/12-SP5/html/SLES-all/cha-y2-userman.html#sec-y2-userman-adv-quota
2. SLES 15 : https://documentation.suse.com/sles/15-SP4/html/SLES-all/cha-yast-userman.html#sec-yast-userman-adv-quota

• Some useful man pages referred during the course of setting quota

1. man xfs
2. man xfs_quota
3. man dracut.cmdline