I’m experiencing an issue with project quotas on an ext4 filesystem, specifically with the hard limit not blocking writes when exceeded.

Here are the steps I’ve taken to set up project quotas:

1. Check mount and modules loaded:

# mount | grep /data
/dev/sdb on /data type ext4 (rw,relatime,prjquota)

2. Create a Test Folder:

# mkdir /data/TestFolder

3. Define Projects:

# echo "TestFolder:100" > /etc/projid
# echo "100:/data/TestFolder" > /etc/projects

4. Set Project Quota Attributes:

# chattr +P -p 100 /data/TestFolder

5. Set Project Quotas:

# setquota -P -t 0 0 -a /data
# setquota -P TestFolder 100M 110M 0 0 /data

Disable grace time and set 100Mb/110Mb for soft/hard limits

6. Check Quotas:

# repquota -Ps /data
*** Report for project quotas on device /dev/sdb
Block grace time: 00:00; Inode grace time: 00:00
                        Space limits                File limits
Project         used    soft    hard  grace    used  soft  hard  grace
----------------------------------------------------------------------
TestFolder --      4K  92160K    150M              1     0     0
#0        --     20K      0K      0K               2     0     0

Now, create first testfile for reach soft limit:

# dd if=/dev/zero of=/data/TestFolder/test1.bin bs=1M count=100
sdb: warning, project block quota exceeded.
100+0 records in
100+0 records out
104857600 bytes (105 MB, 100 MiB) copied, 0.0860563 s, 1.2 GB/s

# repquota -Ps /data
*** Report for project quotas on device /dev/sdb
Block grace time: 00:00; Inode grace time: 00:00
                        Space limits                File limits
Project         used    soft    hard  grace    used  soft  hard  grace
----------------------------------------------------------------------
TestFolder +-    101M    100M    110M   none       2     0     0
#0        --     20K      0K      0K               2     0     0

Second test for reach the hard limit:

# dd if=/dev/zero of=/data/TestFolder/test2.bin bs=1M count=100
100+0 records in
100+0 records out
104857600 bytes (105 MB, 100 MiB) copied, 0.0942253 s, 1.1 GB/s

# repquota -Ps /data
*** Report for project quotas on device /dev/sdb
Block grace time: 00:00; Inode grace time: 00:00
                        Space limits                File limits
Project         used    soft    hard  grace    used  soft  hard  grace
----------------------------------------------------------------------
TestFolder +-    201M    100M    110M   none       3     0     0
#0        --     20K      0K      0K               2     0     0