Did Ali (may Allah be pleased with him) wash and bury Salman al-Farsi? And where was he buried? And for how many years did Salman govern Al-Mada'in?

Salman al-Farsi, the great Companion, died in Madain at the end of Uthman ibn Affan's caliphate, and some say at the beginning of Ali ibn Abi Talib's caliphate. He governed Madain for nineteen years. As for the story of Ali ibn Abi Talib washing his body, it is neither authentic in its chain of transmission nor in its text.