I did that for many years on my boat for weeks at a time. I only put the tent up for heavy rain, and in the end I went to a bivy bag for rainy nights. My tent has no floor which made life really easy, it is a Black Diamond mega mid. Main concern was water dripping (or pouring) from the front deck into the cockpit. It was a bit rigged when it was up but it worked great. My caution, and you probably already know this, is anchoring stern out in any kind of an un protected anchorage. You could sink real fast…. That being said i used an ice picket as a sand stake and a stern anchor. sandy beach I would pull up and use an old motorcycle tire with some holes in it for drainage and pull right up onto it to protect the bow from chafing. The only part of the boat that touches anything is the bow on the tire. A few stern lines and you are set in all but the worst. Most of the time I just used my Paco pad on the back deck. Enjoy!
ps: another option:
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