when use dib in docker, loopdev attach -- losetup ... failed

[peihp2009]

Using a centos:7 docker image, i run a container and do the following operations.

In my host machine:
#docker pull centos:7
#docker run -it --privileged=true --name hp-dib centos:7 bash

Enter the container:
#git clone https://opendev.org/openstack/diskimage-builder.git
#yum -y install bzip2 util-linux dosfstools gdisk kpartx sudo curl git squashfs-tools qemu-img policycoreutils-python procps-ng
#cd /diskimage-builder
#git checkout 2.9.0 （i use the 2.9.0 tag to support python2）
#pip install -r requirements.txt
#python setup.py install
#diskimage-builder -o /opt/centos7.qcow2 vm centos7

------------------------------------------------------------------>
the error happend :

...
...
...
Calculating image size (this may take a minute)...
2021-04-19 03:56:19.552 INFO diskimage_builder.block_device.blockdevice [-] Wrote final block device config to [/tmp/dib_build.HXVBq69a/states/block-device/config.json]
2021-04-19 03:56:20.186 INFO diskimage_builder.block_device.blockdevice [-] create() called
2021-04-19 03:56:20.188 INFO diskimage_builder.block_device.level0.localloop [-] Create image file [/tmp/dib_image.27AEiozV/image0.raw]
2021-04-19 03:56:20.189 INFO diskimage_builder.block_device.level0.localloop [-] loopdev attach
losetup: /tmp/dib_image.27AEiozV/image0.raw: failed to set up loop device: No such file or directory
2021-04-19 03:56:20.221 ERROR diskimage_builder.block_device.level0.localloop [-] losetup failed
2021-04-19 03:56:20.222 ERROR diskimage_builder.block_device.blockdevice [-] Create failed; rollback initiated
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/blockdevice.py", line 385, in cmd_create
    node.create()
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/level0/localloop.py", line 110, in create
    block_device = loopdev_attach(self.filename)
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/level0/localloop.py", line 54, in loopdev_attach
    raise BlockDeviceSetupException("losetup failed")
BlockDeviceSetupException: losetup failed
2021-04-19 03:56:20.223 INFO diskimage_builder.block_device.level0.localloop [-] Remove image file [/tmp/dib_image.27AEiozV/image0.raw]
2021-04-19 03:56:20.224 ERROR diskimage_builder.block_device.blockdevice [-] Rollback complete, exiting
Traceback (most recent call last):
  File "/usr/bin/dib-block-device", line 10, in <module>
    sys.exit(main())
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/cmd.py", line 120, in main
    return bdc.main()
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/cmd.py", line 115, in main
    self.args.func()
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/cmd.py", line 36, in cmd_create
    self.bd.cmd_create()
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/blockdevice.py", line 385, in cmd_create
    node.create()
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/level0/localloop.py", line 110, in create
    block_device = loopdev_attach(self.filename)
  File "/usr/lib/python2.7/site-packages/diskimage_builder/block_device/level0/localloop.py", line 54, in loopdev_attach
    raise BlockDeviceSetupException("losetup failed")
diskimage_builder.block_device.exception.BlockDeviceSetupException: losetup failed
2021-04-19 03:56:20.881 INFO diskimage_builder.block_device.blockdevice [-] State already cleaned - no way to do anything here
*** /tmp/dib_build.HXVBq69a/mnt is not a directory
<-----------------------------------------------------------------------------------------

the error codes in/usr/lib/python2.7/site-packages/diskimage_builder/block_device/level0/localloop.py :

def loopdev_attach(filename):
    logger.info("loopdev attach")
    logger.debug("Calling [sudo losetup --show -f %s]", filename)
    subp = subprocess.Popen(["sudo", "losetup", "--show", "-f",
                             filename], stdout=subprocess.PIPE)
    rval = subp.wait()
    if rval == 0:
        # [:-1]: Cut of the newline
        block_device = subp.stdout.read()[:-1].decode("utf-8")
        logger.info("New block device [%s]", block_device)
        return block_device
    else:
        logger.error("losetup failed")
        raise BlockDeviceSetupException("losetup failed")
<---------------------------------------------------------------------------------------->

What should i do to resolve this problem ? thanks~

[Ian Wienand (iwienand)]

We use dib in docker for all the nodepool-builders, so it should work. Are you running this as a privileged container?

I'm not aware of anything that would stop 2.9.0 working, but honestly it's so far behind I wouldn't be surprised if things aren't work.

[peihp2009 (peihp2009)]

when i use the latest code, the same problem still exists.

the latest code support python3,so i installed python3.

this is a privileged container,becasue i use "docekr run --privileged=true".

---------------------------------------------------->
2021-04-19 09:15:40.563 | Calculating image size (this may take a minute)...
2021-04-19 09:15:41.850 | INFO diskimage_builder.block_device.blockdevice [-] Wrote final block device config to [/tmp/dib_build.RComQZ3I/states/block-device/config.json]
2021-04-19 09:15:42.631 | INFO diskimage_builder.block_device.blockdevice [-] create() called
2021-04-19 09:15:42.633 | INFO diskimage_builder.block_device.level0.localloop [-] Create image file [/tmp/dib_image.uF2GpEg8/image0.raw]
2021-04-19 09:15:42.634 | INFO diskimage_builder.block_device.level0.localloop [-] loopdev attach
2021-04-19 09:15:42.634 | INFO diskimage_builder.block_device.utils [-] Calling [sudo losetup --show -f /tmp/dib_image.uF2GpEg8/image0.raw]
2021-04-19 09:15:42.659 | ERROR diskimage_builder.block_device.blockdevice [-] Create failed; rollback initiated
2021-04-19 09:15:42.659 | Traceback (most recent call last):
2021-04-19 09:15:42.659 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/block_device/blockdevice.py", line 407, in cmd_create
2021-04-19 09:15:42.659 | node.create()
2021-04-19 09:15:42.659 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/block_device/level0/localloop.py", line 101, in create
2021-04-19 09:15:42.659 | block_device = loopdev_attach(self.filename)
2021-04-19 09:15:42.659 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/block_device/level0/localloop.py", line 44, in loopdev_attach
2021-04-19 09:15:42.659 | block_device = exec_sudo(["losetup", "--show", "-f", filename])
2021-04-19 09:15:42.659 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/block_device/utils.py", line 143, in exec_sudo
2021-04-19 09:15:42.659 | raise e
2021-04-19 09:15:42.659 | diskimage_builder.block_device.exception.BlockDeviceSetupException: exec_sudo failed
2021-04-19 09:15:42.659 | INFO diskimage_builder.block_device.level0.localloop [-] Remove image file [/tmp/dib_image.uF2GpEg8/image0.raw]
2021-04-19 09:15:42.663 | ERROR diskimage_builder.block_device.blockdevice [-] Rollback complete, exiting
2021-04-19 09:15:42.664 | Traceback (most recent call last):
2021-04-19 09:15:42.664 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/lib/dib-block-device.py", line 7, in <module>
2021-04-19 09:15:42.664 | sys.exit(main())
2021-04-19 09:15:42.664 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/block_device/cmd.py", line 120, in main
2021-04-19 09:15:42.664 | return bdc.main()
2021-04-19 09:15:42.664 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/block_device/cmd.py", line 115, in main
2021-04-19 09:15:42.665 | self.args.func()
2021-04-19 09:15:42.665 | File "/usr/local/lib/python3.6/site-packages/diskimage_builder/block_device/cmd.py", line 36, in cmd_create
2021-04-19 09:15:42.665 | self.bd.cmd_create()
2021-04-19 09:15:42.665 | File "/usr/local/lib/python3.6/site-packages/diskimag...

[Ian Wienand (iwienand)]

> 2021-04-19 09:15:42.633 | INFO diskimage_builder.block_device.level0.localloop [-] Create image file [/tmp/dib_image.uF2GpEg8/image0.raw]

This simply does an open() to a specified size, I don't see how that could fail really.

> 2021-04-19 09:15:42.634 | INFO diskimage_builder.block_device.utils [-] Calling [sudo losetup --show -f /tmp/dib_image.uF2GpEg8/image0.raw]

it seems like this can't find the file "image0.raw"?

What happens if you do something like

 dd if=/dev/zero of=/tmp/disk.img bs=1M count=10
 sudo losetup --show -f /tmp/disk.img

?

[peihp2009 (peihp2009)]

sorry, I try the #3 resolution way, but it not working.