FAQs

driftfix 'slew' Warning

Cause: The current QEMU model does not support the driftfix=slew parameter.

Solution:

sudo crudini --set /etc/nova/nova.conf libvirt hw_machine_type virt
systemctl restart openstack-nova-compute

QEMU Error: device requires xxx bytes, block backend provides xxx bytes

Cause: QEMU_EFI.fd is not aligned with the memory.

Solution: Align with QEMU_EFI.fd. For details, see Deploying EDK2.

QEMU Error: qemu-system-aarch64: -accel kvm: info: [qemu] fix VIRT_MEM range 0xc0000000 - 0x2c0000000

Cause: The lowest address for memory mapping is not configured.

Solution:

# Add the kernel parameter to the compute node.
sudo sysctl -w vm.mmap_min_addr="65536"
# Make it permanently effective.
echo "vm.mmap_min_addr=65536" | sudo tee -a /etc/sysctl.conf

openstack-nova-compute Startup Error: AttributeError: module 'lib' has no attribute 'X509_V_FLAG_NOTIFY_POLICY'. Did you mean: 'X509_V_FLAG_EXPLICIT_POLICY'?

Cause: The versions of OpenSSL and related components are incorrect.

Solution: Reinstall pyopenssl.

pip install pyopenssl==23.2.0
yum install python3-cryptography-35.0.0-1.oe2403sp2 python3-pyOpenSSL-20.0.1-2.oe2403sp2

Python Package Installation Conflict: keystoneauth1.exceptions.http.InternalServerError: Internal Server Error (HTTP 500)

Cause: The version of the Python package on which OpenStack depends is incorrect.

Solution: Check the sources of the Jinja2, Urllib3, Requests, and MarkupSafe packages. If a package is not from the OpenStack_Wallaby repository, there is a high probability that a package conflict occurs. In this case, uninstall the package and reinstall it.

yum list installed |grep xx
rpm -e xx --nodeps
yum install xx
yum list installed |grep xx

su -s /bin/sh -c "keystone-manage db_sync" keystone
systemctl restart httpd

cVM Deployment Error: No valid host found

Cause: The compute node does not detect the secure memory, or the secure memory information of the compute node is not synchronized to the controller node.

Solution:

Check the OpenStack resource usage by following instructions in Querying VM Information. Check whether the storage and CPU resources are sufficient and whether the secure memory information is obtained. If no secure memory information exists, check the following items in sequence.

Whether the TMM driver is installed.
```
lsmod | grep tmm_driver
```
Whether virtCCA is enabled. The value 1 indicates that virtCCA is enabled.
```
cat /sys/kernel/tmm/virtcca_enabled
```
Whether libvirt identifies virtCCA.
```
virsh domcapabilities | grep virtcca
```

If any of the preceding items fails, perform the following operations.

Install the TMM driver.
```
insmod tmm_driver.ko
```
Clear the libvirt node information cache. Restart the libvirt process and check that libvirt can identify virtCCA.
```
rm -rf /var/cache/libvirt/qemu/capabilities/*
systemctl restart libvirtd
virsh domcapabilities | grep virtcca
```

Restart httpd and nova-compute.

systemctl restart httpd openstack-nova-compute

SR-IOV Timeout, neutron-openvswitch Startup Failure, and neutron-dhcp Error Reported: Failed reporting state!: oslo_messaging.exceptions.MessagingTimeout: Timed out waiting for a reply to message ID

Cause: The DPDK parameter is configured for Open vSwitch. Therefore, Open vSwitch cannot be started when the DPDK service has not been started.

Solution:

Delete the DPDK parameter of Open vSwitch.

ovs-vsctl --no-wait remove Open_vSwitch . other_config dpdk-init
ovs-vsctl --no-wait remove Open_vSwitch . other_config dpdk-socket-mem
ovs-vsctl --no-wait remove Open_vSwitch . other_config dpdk-lcore-mask
ovs-vsctl --no-wait remove Open_vSwitch . other_config pmd-cpu-mask
ovs-vsctl --no-wait remove Open_vSwitch . other_config dpdk-pmd-driver
ovs-vsctl --no-wait remove Open_vSwitch . other_config vhost-iommu-support

Check whether Open vSwitch has the DPDK parameter. If false is returned, the DPDK parameter has been deleted.
```
ovs-vsctl get Open_vSwitch . dpdk_initialized
```

Restart the service.

systemctl restart openvswitch neutron-openvswitch

Parent topic: Feature Guide