Re: How to change nova db in Train ?

I think technically you can use 403 for your Train backport as there was no newer migration ever merged. But I hope others more experience with DB migration backporting in Nova can confirm this.

Yes, 403 is a placeholder for backports *from* Ussuri, to Train. However, I don't think the stated change is a reasonable candidate for a schema backport. They really should only be used for critical regressions that can't be fixed any other way. Since the length of that column hasn't changed lately, I wouldn't call it a regression, and definitely not critical. Going forward we can expand the size in master, if need-be, but I would not support backporting that change. --Dan