My son is 15 months. He has shown interest, but i know he isn't full out ready. So I bought him a little potty. Everytime I go, I take off his diaper and put him on it so he gets used to it. Soon when he gets up in the morning and after naps, I'll be putting him on there. When they wake up, they usually do need to go.
I am not pushing it, but kind of letting him get used to things. Don't push or else everything will come crashing down. Just keep following her cues. And if she has allergy's to diaper's and she's miserable, I'd try. I would get panties because pull ups and diapers make it so that babies don't have to care about it. It's a portable toilet for them. So set aside several days where you don't go anywhere and just put her in the big girl panties and follow her cues and put her on the potty. I would search here for potty training 17 month old. I found a lot of good tips.