Musannaf Ibn Abi Shaybah

Hazrat Ibn Umar (may Allah be pleased with both of them) saw a person in the state of Ihram who was taking shade with a stick. He said: Make yourself apparent for the One for whom you have put on Ihram (do not go into the shade, remain in the sun).

Hazrat Abdullah bin Aamir narrates that I set out for Hajj with Hazrat Umar. Throughout the journey, I did not see him pitching a tent. He was asked, "With what did Hazrat Umar take shade?" Hazrat Abdullah bin Aamir replied that he would throw a piece of leather over a tree and take shade from it.

Hazrat Mutlib bin Abdullah bin Hantab narrates that when the noble companions would enter into the state of Ihram, they would expose themselves (they would not go into the shade).