[refurb]

It is. All a backdoor Roth does is it gets around the income limits for Roth IRAs. If you make more than ~$130K per year, you aren't allowed to contribute.

With a backdoor Roth, you contribute to a normal, post tax IRA, then convert to Roth. However, if you have a rollover IRA, then you can't do it without taking a tax hit.

However, I have heard of people putting more than $5500 per year in a Roth. Search for it on the Bogleheads forum. I can't remember the details, but your employer needs to be on board as you contribute to a 401k, then do some conversion.