Flows not created intermittently
Affects | Status | Importance | Assigned to | Milestone | ||
---|---|---|---|---|---|---|
Juniper Openstack | Status tracked in Trunk | |||||
R1.1 |
In Progress
|
Undecided
|
Anand H. Krishnan | |||
R2.0 |
Fix Committed
|
Undecided
|
Anand H. Krishnan | |||
R2.1 |
Fix Committed
|
Undecided
|
Anand H. Krishnan | |||
Trunk |
Fix Committed
|
Undecided
|
Anand H. Krishnan |
Bug Description
1. It was observed that many compute nodes have flows in HOLD state. Ideally, HOLD state should only be a temporary state. When Vrouter kernel module identifies a new flow, it allocates an entry from flow-table puts it in HOLD state and sends message to Agent for flow setup. Once agent programs the flow the action moves from HOLD to FORWARD/DENY/etc… as appropriate.
2. It was observed that randomly new flow sessions do not get setup.
1. Vrouter kernel module is receiving packets
2. No flows are being created by Vrouter module
3. No packets trapped on pkt0 for flow-setup
4. No logs in agent trace-buffer for flows
5. Vrouter dropstats show that “Flow Unusable” keeps incrementing
3. If flows in HOLD state deleted, the session gets setup and works fine. Note, the flows in HOLD state are not related to the new flow being setup.
The “Flow Unsable” counter is incremented when number of flows in HOLD state exceed a limit in Vrouter.
Based on the observations, the current suspect is accounting of flows in HOLD state has gone bad. As a result new flows are not being setup. Once flows in HOLD state are manually deleted the flows resume.
information type: | Proprietary → Public |
Review in progress for https:/ /review. opencontrail. org/8881
Submitter: Anand H. Krishnan (<email address hidden>)