4.2.4. OpenStack

This section gathers issues that happen with Virtual Service Router started in an OpenStack environment.

VM start errors

Symptoms
  • My VM can’t start, or is in a bad state (NOSTATE):

    $ nova list
    +--------------------------------------+------+--------+------------+-------------+------------------------------+
    | ID                                   | Name | Status | Task State | Power State | Networks                     |
    +--------------------------------------+------+--------+------------+-------------+------------------------------+
    | 52ad953d-19dd-47a9-b03d-dfe565e655e1 | vm3  | ERROR  | -          | NOSTATE     |                              |
    | b28e5aa1-05c9-494b-8f0e-0247d95bde87 | vm2  | ACTIVE | -          | Running     | private2=12.0.0.3            |
    | c4a52ed6-775d-45b3-96c2-8c2a6a1530ac | vm1  | ACTIVE | -          | Running     | private=11.0.0.6, 172.24.4.3 |
    +--------------------------------------+------+--------+------------+-------------+------------------------------+
    
Hints
  • Check the /var/log/nova/nova-compute.log file for ERROR. Considering the output, check the following issues.

Not enough memory

Symptoms

My VM can’t start, or is in a bad state (NOSTATE). On the compute node hosting the VM. /var/log/nova/nova-compute.log shows ERRORs and TRACEs like those:

Error launching a defined domain with XML: <domain type='kvm'>
[instance: 52ad953d-19dd-47a9-b03d-dfe565e655e1] Instance failed to spawn
...
...: unable to map backing store for hugepages: Cannot allocate memory
Hints
  • Add more memory to your compute node.

Cannot use hugepages of 1GB

Symptoms

Nova displays an error “Unable to find any usable hugetlbfs mount”.

On the controller node, /var/log/nova/nova-conductor.log shows ERRORs and TRACEs like this one:

error: Unable to find any usable hugetlbfs mount for 1048576 KiB
Hints
  • Hugepages cannot be allocated for the VM. It may be due to the size of the hugepages. Try to allocate more but smaller hugepages.

Performance degradation and security groups

Symptoms
  • VM packet processing is slower than expected.

Hints
  • Consider disabling security groups as numerous packets processing require many iptables/ebtables look-ups to direct packets properly when they’re enabled.

    Refer to OpenStack documentation on how to do that considering your running version.