OVS currently can gracefully exit in two ways: either with or without deleting the datapath. But, either way, it deletes all of the flows from the datapath before it exits. That is due to commit e96a5c24e853 ("upcall: Remove datapath flows when setting n-threads."), which was first released in OVS 2.1 back in 2014.
This isn't usually a big deal. However, some controller folks I'm talking to are concerned about upgrade. If the datapath flows persisted after OVS exits, then existing network connections (and perhaps some that are "similar" to them because they match the same megaflows) could carry on while the upgrade was in progress. I am surprised that I have not heard complaints about this in the 5 years that the behavior has been this way. Does anyone have any stories to report about it now that I bring it up? Contrariwise, if we changed OVS so that it did not delete datapath flows on exit, can anyone suggest what problems that might cause? Thanks, Ben. _______________________________________________ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss