Allah's Messenger (ﷺ) used to pray eleven rak`at at night and that was his night prayer and each of his prostrations lasted for a period enough for one of you to recite fifty verses before Allah's Messenger (ﷺ) raised his head. He also used to pray two rak`at (Sunnah) before the (compulsory) Fajr prayer and then lie down on his right side till the Mu'adh-dhin came to him for the prayer.
Sahih al-Bukhari Book 14, Hadith 5
← Previous Hadith The Prophet (ﷺ) said, "Night prayer is offered as two rak`at followed by two rak`at and so on, and if you want to finish it, pray only one rak`a which will be witr for all the previous rak`at." Al-Qasim said, "Since we attained the age of puberty we have seen some people offering a three-rak`at prayer as witr and all that is permissible. I hope there will be no harm in it."

Sahih al-Bukhari Book 14, Hadith 4 Next Hadith → I asked Ibn `Umar, "What is your opinion about the two rak`at before the Fajr (compulsory) prayer, as to prolonging the recitation in them?" He said, "The Prophet (ﷺ) used to pray at night two rak`at followed by two and so on, and end the prayer by one rak`ah witr. He used to offer two rak`at before the Fajr prayer immediately after the Adhan." (Hammad, the sub-narrator said, "That meant (that he prayed) quickly.)"

Sahih al-Bukhari Book 14, Hadith 6