I sterilize my jars in in the dishwasher. I have two canning pots for BWB and they both have a little rust. I still use them. So I hope the experts chime in and say that's ok!

Dishwashers don't sterilize, they just sanitize. Boiling the jars for 10 mins. will sterilize but you don't need sterilized jars for anything that will be processed for 10 mins. or longer. That leaves very few recipes that require sterile jars.

In most cases the rust, at least most of it can be removed by scrubbing/scouring. A few small rust spots is one thing but personally I wouldn't use a pot that was very rusty as under certain circumstances water from the pots may be vacuumed back into the jars of food. It is your choice.

Dave

I wouldn't have a safety concern per se (I mean in terms of safety of jar contents.) but I might have a functional one. If there's a spot on the side or bottom that's quite thin and it gives under the weight of the jars and water, then you will be dealing with a scalding and, pardon me, unholy mess in your kitchen.

Superficial rust would not be a bother. Those kettles and especially the racks rust very easily.

Carol