Why I did it
The initial value has to be present for the state machines to work. In active-standby dual-tor scenario, or any hardware mux scenario, the value will be updtaed eventually with a delay.
However, in active-active dual-tor scenario, there is no other mechanism to initialize the value and get state machines started.
So this script will have to write something at start up time.
For active-active dualtor, 'active' is a more preferred initial value, the state machine will switch the state to standby soon if
link prober found link not in good state.
How I did it
Update the script to always provide initial values.
How to verify it
Tested on active-active dual-tor testbed.
Signed-off-by: Ying Xie ying.xie@microsoft.com
Avoid write_standby in warm restart context.
sign-off: Jing Zhang zhangjing@microsoft.com
Why I did it
In warm restart context, we should avoid mux state change.
How I did it
Check warm restart flag before applying changes to app db.
How to verify it
Ran write_standby in table missing, key missing, field missing scenarios.
Did a warm restart, app db changes were skipped. Saw this in syslog:
WARNING write_standby: Taking no action due to ongoing warmrestart.
[write_standby]: Ignore non-auto interfaces
* In the event that `write_standby.py` is used to automatically switchover interfaces when linkmgrd or bgp crashes, ignore any interfaces that are not configured to auto-switch
Signed-off-by: Lawrence Lee <lawlee@microsoft.com>
