What test did Penelope set for he beggar to prove he was Odysseus?

Rather than directly testing Odysseus and questioning him, Penelope asks her maid Eurycleia to move the great bed that Odysseus himself made with his own hands.

This is a clever way of testing Odysseus because the bed was made in a way that would be near impossible to move and Odysseus finds Penelopes Words 'a knife in [his] heart'

The bed was made by using the trunk of an olive tree as the first bedpost, the tree was still rooted to the ground so Odysseus claims that even a man in his prime wouldn't be able to move the bed.

Odysseus and Penelope are the only people to know how the bed was created so Odysseus has just give proof that he truly is who he says he is.