(In reply to Alex Jia from comment #0)
> [root@kvm-07-guest10 ~]# podman rm -f support-tools
> WARN[0000] lstat
> /sys/fs/cgroup/devices/machine.slice/libpod-
> 26b987c9d039968bb4e3206ff572d08c5d4d886eee079922a419f5bfb398c827.scope: no
> such file or directory 
> 26b987c9d039968bb4e3206ff572d08c5d4d886eee079922a419f5bfb398c827
> 

BTW, is it a necessary WARN in here?

I actually think that this was touched during one of the meetings that we had in past about the rebase with Derrick and Scott. My impression was that the backwards compatibility is not a problem if it's documented. On the other hand if it would be easy to somehow maintain the backwards compatibility, then it would be appreciated by our customers.

The new toolbox will completely error out if old toolbox was ever run on the system.  

Reproducer:

1. Run old bash script toolbox once and exit:

# /tmp/rhcos-toolbox 
Spawning a container 'toolbox-root' with image 'registry.redhat.io/rhel8/support-tools'
Detected RUN label in the container image. Using that as the default...

[root@rhel84 /]# exit
exit


2.  Run new toolbox:

# rpm -q toolbox
toolbox-0.0.99.3-0.3.module+el8.5.0+12372+12f82d56.x86_64

# toolbox --version
toolbox version 0.0.99.2

# toolbox create
Error: TOOLBOX_PATH not set



The cause is that using old toolbox we mounted host /run to container /run (-v /run:/run), and the container creates a /run/.containerenv file that's supposed to only live in the container.  We basically leaked it out of the container.
Removing the file on the host fixes the problem:

# rm -f /run/.containerenv 

# toolbox create
Created container: support-tools-latest
Enter with: toolbox enter



We essentially break everyone that's used toolbox before. I feel like we should handle this in some way.  The backwards compatibility discussions we had previously were around the config options and UX/CLI changes.  Those are acceptable changes.

> We essentially break everyone that's used toolbox before.
> I feel like we should handle this in some way.  The backwards
> compatibility discussions we had previously were around
> the config options and UX/CLI changes.  Those are acceptable
> changes.

How do you want to handle it?

Is it enough if the following error message said something else:
  [root@kvm-07-guest10 ~]# toolbox enter support-tools
  Error: container support-tools is too old and no longer supported 
  Recreate it with Toolbox version 0.0.17 or newer.

The fact that a /run/.containerenv gets placed on the host is a bit thorny. We might be able to carefully side-step it, but it depends on what we exactly decide to do.

I think the simplest solution might be: if env variables $TOOLBOX_PATH and $container are not set and file /run/.containerenv exists, then print an error indicating the user may need to manually remove /run/.containerenv from their system.  

This at least hints at how to resolve the issue.  We'll likely create a kbase solution customers can search for that will explain the issue in more detail.

> I think the simplest solution might be: if env variables
> $TOOLBOX_PATH and $container are not set and file
> /run/.containerenv exists, then print an error indicating
> the user may need to manually remove /run/.containerenv
> from their system.

Ok, this sounds doable.

I got a patch that does:
  [root@kvm-07-guest10 ~]# toolbox enter support-tools
  Error: /run/.containerenv found on what looks like the host
  If this is the host, then remove /run/.containerenv and try again.
  Otherwise, contact your system administrator or file a bug.

Does it look OK?

Looks good to me, thanks!

Built toolbox-0.0.99.3-0.3.module+el8.5.0+12477+44413d02:
https://brewweb.engineering.redhat.com/brew/buildinfo?buildID=1717786

This bug has been verified on toolbox-0.0.99.3-0.3.module+el8.5.0+12477+44413d02.

[root@hpe-dl380pgen8-02-vm-8 ~]# rpm -q toolbox
toolbox-0.0.99.3-0.3.module+el8.5.0+12477+44413d02.x86_64

[root@hpe-dl380pgen8-02-vm-8 ~]# toolbox
Error: /run/.containerenv found on what looks like the host
If this is the host, then remove /run/.containerenv and try again.
Otherwise, contact your system administrator or file a bug.
[root@hpe-dl380pgen8-02-vm-8 ~]# rm -rf /run/.containerenv
[root@hpe-dl380pgen8-02-vm-8 ~]# toolbox
⬢[root@toolbox ~]# echo $HOST
/run/host
⬢[root@toolbox ~]# exit
logout
[root@hpe-dl380pgen8-02-vm-8 ~]# echo $?
0

Closing this bug as VERIFIED per Comment 15.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (Moderate: container-tools:rhel8 security, bug fix, and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2021:4154