Is it permissible to fast on the second day of Eid al-Fitr, and is Eid more than one day?

There is no harm in fasting on the second day of Eid al-Fitr; rather, it is encouraged to hasten in making up for any missed fasts from Ramadan. The legitimate day of Eid is only one day. However, the prohibition of fasting on Eid al-Adha includes the Days of Tashreeq (the eleventh, twelfth, and thirteenth of Dhul-Hijjah), due to the Prophet, peace and blessings be upon him, saying: "The days of Mina are days of eating, drinking, and remembering Allah, the Most High."