Sai Mahabhakta Shri.Hari Kanoba’s mention has been made in Chapter 49 of holy Shri Sai Satcharitra.

Shri.Hari Kanoba was a resident of Mumbai. He had heard from his friends and relatives about many leelas performed by Shri.Sai Baba. But he did not believe in Baba and wanted to test Him. So he came to Shirdi along with some Mumbai friends.He wore a lace-bordered turban on his head and a new pair of sandals on his feet. Seeing Baba from a distance he thought of going to Him and prostrating himself before Him. He did not know what to do with his new sandals. Still going to some corner outside in the open courtyard, he placed them there and went inside the Dwarakamai Masjid and took Baba's darshan. He made a reverential bow to Baba, took udi and prasad from Baba and returned. When he reached the corner he found that his sandals had disappeared. He searched for them in vain and returned to his lodging very much dejected.

He bathed, offered worship and naivedya and sat for meals, but all the while he was thinking about nothing but his sandals. After finishing his meals, he came out to wash his hands when he saw a Maratha boy coming towards him. He had in his hand a stick, on the top of which was suspended a pair of new sandals. He said to the men who had come out to wash their hands that Baba sent him with this stick in hand and asked him to go on the streets crying - "Hari Ka Beta. Jari Ka Pheta" and told him that "If anybody claims these sandals, first assure yourself that his name is Hari and that he is the son of Ka, i.e., Kanoba, and that he wears a lace-bordered turban and then give them to him." Hearing this, Hari Kanoba was pleasantly surprised. He went ahead to the boy and claimed the sandals as his own. He said to the boy that his name was Hari and that he was the son of Ka (Kanoba) and showed him his lace-bordered turban. The boy was satisfied and returned the sandals to him. Hari Kanoba wondered in his mind saying that his lace-bordered turban was visible to all and Baba might have seen it, but how could he know his name Hari and that he was the son of Kanoba, as this was his first trip to Shirdi. He came there with the sole object of testing Baba and with no other motive. He came to know by this incident that Baba was a great Satpurush. He got what he wanted and returned home well-pleased.

(Source: Shri Sai Satcharitra, Chapter 49)