We found SUDDENLY that OPSF with hello-timer=1 on the Huawei NE40E got convergency more then 20 seconds. And any changing of timers is not helped.
We have schemes with such timer value, the reason is some old equipment without BFD. And everything worked fine 1-2 month ago.
Official Huawei TAC respond
For mitigation OSPF flaping, minimal value for dead-timer was 10 seconds (starting from version V600R003 ) and is 20 seconds (starting from version V600R005), regardless of values OSPF timers on the interface.
Do you understand?
REGARDLESS. “Do you want dead-timer value less than 20 seconds? It is your problem. We don’t care… But your OSPF is not flapping now! Hooray!”
And then somebody asks “Why do you not like Huawei?”