Dear All, We are upgrading one of our openstack cluster from ussuri to wallaby and for this we are first upgrading OS of lxc container from ubuntu to 18 to 20(hosts OS is also upgraded to 20). We are destroying LXC containers(which don't form quorum like nova,neutron,heat,cinder,horizon) of one infra node and then creating it again. The new containers are getting created with Ubuntu 20 as the host OS is 20. Playbook for cinder, nova neutron were completed successfully for new containers of ubuntu 20. But Playbook is failing for heat, placement and memcached due to python version mismatch: fatal: [host5_heat_api_container-25f90e52]: FAILED! => {"attempts": 5, "changed": false, "cmd": ["/openstack/venvs/heat-21.2.5/bin/pip3", "install", "-U", "--constraint", "/openstack/venvs/heat-21.2.5/global-constraints.txt", "--constraint", "/openstack/venvs/heat-21.2.5/constraints.txt", "--pre", "--log", "/var/log/python_venv_build.log", "cryptography", "keystonemiddleware", "openstack-heat", "osprofiler", "pymemcache", "PyMySQL", "python-ceilometerclient", "python-glanceclient", "python-heatclient", "python-keystoneclient", "python-memcached", "python-neutronclient", "python-novaclient", "python-openstackclient", "python-swiftclient", "python-troveclient", "systemd-python"], "msg": "stdout: Ignoring python-saharaclient: markers 'python_version == \"2.7\"' don't match your environment\nIgnoring python-saharaclient: markers 'python_version == \"3.6\"' don't match your environment\nIgnoring python-saharaclient: markers 'python_version == \"3.7\"' don't match your environment\nIgnoring oslo.limit: markers 'python_version == \"2.7\"' don't match your environment\nIgnoring oslo.limit: markers 'python_version == \"3.6\"' don't match your environment\nIgnoring oslo.limit: markers 'python_version == \"3.7\"' don't match your environment\nIgnoring sphinxcontrib-actdiag: markers 'python_version == \"2.7\"' don't match your environment\nIgnoring sphinxcontrib-actdiag: markers 'python_version == \"3.6\"' don't match your environment\nIgnoring sphinxcontrib-actdiag: markers 'python_version == \"3.7\"' don't match your environment\nIgnoring os-api-ref: markers 'python_version == \"2.7\"' don't match your environment\nIgnoring os-api-ref: markers 'python_version == \"3.6\"' don't match your environment\nIgnoring os-api-ref: markers 'python_version == \"3.7\"' don't match your environment\nIgnoring oslo.concurrency: markers 'python_version == \"2.7\"' don't match your environment\nIgnoring oslo.concurrency: markers 'python_version == \"3.6\"' don't match your environment\nIgnoring oslo.concurrency: markers 'python_version == \"3.7\"' don't match your environment\nIgnoring osprofiler: markers 'python_version == \"2.7\"' don't match your environment\nIgnoring osprofiler: markers 'python_version == \"3.6\"' don't match your environment\nIgnoring osprofiler: markers 'python_version == \"3.7\"' don't match your environment\nIgnoring os-resource-classes: markers 'python_version == \"2.7\"' don't match your environment\nIgnoring os-resource-classes: markers 'python_version == \"3.6\"' don't match your environment\nIgnoring os-resource-classes: markers I understand that 2.7 version is depricated but where should make changes to fix it? https://docs.openstack.org/releasenotes/python-heatclient/ussuri.html I tried updating few variable to fix python version like: /etc/ansible/roles/os_heat/defaults/main.yml #heat_venv_python_executable: "{{ openstack_venv_python_executable | default('python3') }}" updated it from python2 to python 3 Tried few more variables but that didn't work. Any idea how we can fix this version mismatch issue ? Regards, Danish