How could a feudal government allow local landowners to be armed? It had to?

There were different kinds of feudal governments A truly feudal government would allocate land to its subjects according to rank, and the subjects would have varying degrees of power, some would have armies, some would have administrative power, and the subjects would be required to fulfill their obligations as subjects and pay tribute on time, and if the monarch needed you to send troops, you had to send troops. The Middle Ages, with the exception of China, most of the world was ruled in this manner, with the monarchs having less power, and in China, power had been completely transferred to the central government from the mid- to late-Han Dynasty onward. In China, since the mid to late Han Dynasty, the power has been completely transferred to the central government, and there are no local armies allowed, except in the case of civil unrest, where rebels and uprisings are swarming, and the central government can't control them, then the local government will allow the locals to recruit their own soldiers to fight against the rebels, like the Ching Dynasty, during the Taiping Rebellion, they had to rely on the local strongest people to set up their own regimentation to fight against the Taiping Army.