In Book Seventeen of this epic classic, Odysseus is abused by Melanthius the goatherd. The biggest trial Odysseus has here is trying to restrain himself from killing the repugnant goatherd, which he manages to do. When Odysseus, accompanied y Eumaeus, enters the place, where the plan is that Odysseus, disguised as a beggar will plead for his supper, Argos, the dog of Odysseus, greets his master and dies. Odysseus enters the palace and Telemachus gives his father a meal and then bids him beg from among the suitors. The suitors do show some compassion, but Antinoos, who, to be fair is provoked by Odysseus, throws a stool at him.
In Book Eighteen, Odysseus is told to leave by Iros, a mendicant. The two characters fight and the suitors greatly enjoy the entertainment that this battle gives them. Odysseus receives criticism from the handmaidens of Penelope when he says that he will man the fires and that they should retreat to the upper chamber, but he quickly asserts his authority and they leave swiftly. Eurymachus is angered by Odysseus and suggests that he would rather beg than work. When Odysseus offers to outperform him in any task, Eurymachus throws a stool at him and wounds a cupbearer.
So, from this brief summary of the main action of Odysseus in these two books, the main trials that he faces regard his disguise and his temptation to show himself for who he really is. However, because of his plan, he must play the part of the disguised beggar forced to ask for his food, and therefore is not able to kill the suitors or challenge them openly, or declare himself before his wife. Thus we can understand the immense frustration of Odysseus in this situation.