Podman commands throw error, 'user namespaces are not enabled in /proc/sys/user/max_user_namespaces'

Overview of the Issue

This issue occurs in the following circumstances:

  1. An organization is configuring Podman for a vFunction trial
  2. Podman is installed as the Root user and works well for that user
  3. When the Sudoless user who will be doing the vFunction Installation attempts to run Podman commands, the following error is generated
podman ps 
user namespaces are not enabled in /proc/sys/user/max_user_namespaces
Error: cannot re-exec process
  1. Unexpectedly, zero Namespaces are configured
cat /proc/sys/user/max_user_namespaces
0

Steps to Resolve the Issue

Take the following steps to resolve the problem:

  1. SSH to the Linux VM as the root user or with sudo access
  2. Run the following command to modify the max user namespaces on the VM
echo "user.max_user_namespaces=10000" > /etc/sysctl.d/42-rootless.conf
  1. Reload Systemctl
sysctl --system
  1. Switch users back to the Sudoless user who will install vFunction and attempt to again run Podman commands

Updated on 25 Apr 2025