Dzugashvili is not a Russian name.
Read Edvard Radzinsky’s bio of Stalin:
Wonder of wonders this is posted online at:
https://www.washingtonpost.com/wp-srv/style/longterm/books/chap1/stalin.htm
Wherein this paragraph can be found::
“The part of the town in which Beso’s house stood was known as the Russian quarter, because Russian soldiers were stationed in a barracks nearby. So other children often called Soso “the Russian.” This wouldlodge in his subconscious, with strange results. He would never feel the stirring of Georgian nationalist sentiment. Only his first revolutionary pseudonym—almost a childish nickname—had any connection with Georgia. As a professional revolutionary, he used only Russian names when living underground. He would later describe his homeland sarcastically as “that small area of Russia which calls itself Georgia.”