Abdullah bin Umar set out, and when he reached Dhul-Hulayfa, he entered the state of ihram for umrah. He traveled on a short distance and then feared that he might be prevented from reaching the House. He said, "If I am prevented, I will do as the Messenger of Allah ﷺ did." Then he said, "By Allah, the path of hajj is the same as the path of umrah. I call you to witness that I have made hajj obligatory upon myself along with my umrah."He then traveled on until he reached Qudayd, where he purchased a sacrificial animal. He proceeded to Mecca, circled the House seven times, and walked between Safa and Marwa. He said, "This is how I saw the Messenger of Allah ﷺ do it."
أخبرنا علي بن ميمون الرقي قال حدثنا سفيان عن أيوب السختياني وأيوب بن موسى وإسمعيل بن أمية وعبيد الله بن عمر
خرج عبد الله بن عمر فلما أتى ذا الحليفة أهل بالعمرة فسار قليلا فخشي أن يصد عن البيت فقال إن صددت صنعت كما صنع رسول الله ﷺ قال والله ما سبيل الحج إلا سبيل العمرة أشهدكم أني قد أوجبت مع عمرتي حجا فسار حتى أتى قديدا فاشترى منها هديا ثم قدم مكة فطاف بالبيت سبعا وبين الصفا والمروة وقال هكذا رأيت رسول الله ﷺ فعل
[Its chain of transmission is sahih]. Humaydi collected it, no. 679, from Sufyan bin Uyayna through this route, and he stated clearly that he had heard it directly. It is also found in Kubra, no. 3914. The hadith has other routes in Malik, 1/360, and in Bukhari and Muslim and others, through this route.