Cinder Driver Fails to Initialize with “NetApp API failed. Reason-408: Request Timeout”

Applies to

• OpenStack Cinder using NetApp ONTAP drivers
• Red Hat OpenStack Platform (RHOSP)
• Environments with intermediate network devices between Cinder host and ONTAP

Issue

The OpenStack Cinder driver fails to initialize when configured for NetApp ONTAP backend storage. The following error is seen repeatedly in the Cinder logs:

Failed to initialize driver.: cinder.volume.drivers.netapp.dataontap.client.api.NaApiError: NetApp API failed. Reason-408: Request Timeoutcinder.volume.manager urllib.error.HTTPError: HTTPError 408: Request Timeout
cinder.volume.drivers.netapp.dataontap.client.api.NaApiError: NetApp API failed. Reason-408: Request Timeout

Validation:
Run ping tests with increasing packet sizes to check MTU behavior:

Example Commands:
ping -M do -s 1620 <ONTAP-IP>
ping -M do -s 1621 <ONTAP-IP>
ping <ONTAP-IP> vrf <VRF_NAME> packet-size 1620
ping <ONTAP-IP> vrf <VRF_NAME> packet-size 1621

Note:
<VRF_NAME> = Virtual Routing and Forwarding table on a router (e.g., Out-of-Band management VRF).
<ONTAP-IP> = ONTAP cluster management IP.

Sample Outputs :

 Success Case

RHEL3# ping 10.x.x.x vrf <VRF_NAME> packet-size 1620
PING 10.x.x.x (10.x.x.x): 1620 data bytes
1628 bytes from 10.x.x.x: icmp_seq0 ttl=63 time=0.886 ms
1628 bytes from 10.x.x.x: icmp_seq1 ttl=63 time=0.705 ms
1628 bytes from 10.x.x.x: icmp_seq2 ttl=63 time=0.785 ms
1628 bytes from 10.x.x.x: icmp_seq3 ttl=63 time=0.697 ms
1628 bytes from 10.x.x.x: icmp_seq4 ttl=63 time=0.646 ms

--- <IP_ADDRESS> ping statistics ---
5 packets transmitted, 5 packets received, 0.00% packet loss
round-trip min/avg/max = 0.646/0.705/0.886 ms

Failure Case

RHEL3# ping 10.x.x.x vrf <VRF_NAME> packet-size 1621
PING 10.x.x.x (10.x.x.x): 1621 data bytes
Request 1 timed out
Request 2 timed out
Request 3 timed out
Request 4 timed out
Request 5 timed out

--- <IP_ADDRESS> ping statistics ---
5 packets transmitted, 0 packets received, 100.00% packet loss