Ogareff had warned the Grand Duke that an attack was to be feared. He knew, he said, that an assault was to be made, both above and below the town, and he counselled the Duke to reinforce the two directly threatened points. Accordingly, after a council of war had been held in the palace, orders were issued to concentrate the defense on the bank of the Angara and at the two ends of the town, where the earthworks protected the river.

This was exactly what Ogareff wished. He did not expect that the Bolchaia Gate would be left entirely without defenders, but that there would only be a small number. Besides, Ogareff meant to give such importance to the diversion, that the Grand Duke would be obliged to oppose it with all his available forces. The traitor planned also to produce so frightful a catastrophe that terror must inevitably overwhelm the hearts of the besieged.

All day the garrison and population of Irkutsk were on the alert. The measures to repel an attack on the points hitherto unassailed had been taken. The Grand Duke and General Voranzoff visited the posts, strengthened by their orders. Wassili Fedor's corps occupied the North of the town, but with orders to throw themselves where the danger was greatest. The right bank of the Angara had been protected with the few guns possessed by the defenders. With these measures, taken in time, thanks to the advice so opportunely given by Ivan Ogareff, there was good reason to hope that the expected attack would be repulsed. In that case the Tartars, momentarily discouraged, would no doubt not make another attempt against the town for several days. Now the troops expected by the Grand Duke might arrive at any hour. The safety or the loss of Irkutsk hung only by a thread.