My wildcard certificate expires in three weeks and I've just renew it and installed the new certificate, so that my IIS has two now.
I have currently more than 30 sites running and I would like to update them one by one to use the updated certificate. Though I dont see a parameter for appcmd set site which allows me to specify which certificate to use. I really would hate to have to delete the old certificate and re-add all sites asap which means my sites would be without SSL for a few minutes.
Seems like there were no other possibilities, I decided to go ahead and update them manually as quickly as possible. When entering the "Bindings" popup for the first website, it warned me (as usual with https bindings) that multiple sites were detected. I ignored the warning and set the new certificate for the first website. That also updated the https bindings on all the other sites apparently. I have checked with various online SSL checkers and the sites all seems to be updated now. Phew.