>warning: Resource manager configuration is changed, reboot is required to take effect.

If you have deployed a cluster, be sure to reboot all nodes.

--

root@srx4600> show security forward-options resource-manager settings 

Owner     Type           Current settings   Next settings

RE      CPU core number     1           1   

We can see this configuration

forwarding-options {
        family {
            inet6 {
                mode flow-based;
            }
        }
        resource-manager {.    <<<<<<<<
            cpu {
                re 2;
            }
        }
    }

>Enhanced-logging option introduced to assign dedicated CPU resource for on-box logging on SRX4600 in Junos OS Release 23.1R1.

>From Junos OS Release 25.2R1, when you launch vSRX 3.0 instances with even numbers of CPU cores configured, then by default two CPU cores are allocated to the Routing Engine. This allocation enhances system stability and ensures the efficient operation of both the Routing Engine and Packet Forwarding Engine. For systems with an odd number of CPU cores, only one core is allocated to the Routing Engine.

>This command is now deprecated for vSRX 3.0. You cannot manually configure the number of CPU cores on the Routing Engine because the default assignment automatically allocates these cores.

Documentation:

https://www.juniper.net/documentation/us/en/software/junos/cli-reference/topics/ref/statement/security-forwarding-options-resource-manager.html