changefeed can not work due to there was no CDC owner after all pd restart

[Lily2025]

What did you do?

1、run sysbench read_write 2、kill all tikv and pd

3、check data consistency between upstream and downstream

What did you expect to see?

changefeed can work normally after restart all pd

What did you see instead?

Versions of the cluster

Dataflow Engine version (run tiflow version):

./cdc version Release Version: v9.0.0-beta.1-70-gedabce7 Git Commit Hash: edabce7da243f7e5bc9fe7331dbe41ebbab29ba2 Git Branch: HEAD UTC Build Time: 2025-04-17 03:07:36 Go Version: go version go1.23.7 linux/amd64 Failpoint Build: false 2025-04-17T16:36:25.339+0800

[Lily2025]

/severity critical

[Lily2025]

/assign wlwilliamx

[flowbehappy]

Since it is rare case, I suggest we set it to major instead of critical, and only fix it in the new cdc version.