IP flood thresholds, you can also use DoS Protection profiles to detect and prevent session exhaustion attacks in which a large number of hosts (bots) establish as many sessions as possible to consume a target's resources. On the profile's Resources Protection tab, you can set the maximum number of concurrent sessions that the device(s) defined in the DoS Protection policy rule to which you apply the profile can receive. When the number of concurrent sessions reaches its maximum limit, new sessions are dropped. https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-admin/zone-protection-and-dos-protection/zone-defense/dos-protection-profiles-and-policy-rules/dos-protection-profiles.html
https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-admin/zone-protection-and-dos-protection/zone-defense/dos-protection-profiles-and-policy-rules/dos-protection-profiles#ida42d52fa-3366-4695-bb4a-d39ebf3b6a5f

The template stack should consist of four templates arranged according to the diagram. The template values that will be configured on the firewall if each template has an SSL/TLS Service profile configured named Management will be the values in Chicago. This is because the SSL/TLS Service profile is configured in the Chicago template, which is the highest priority template in the stack. The firewall will inherit the settings from the highest priority template that has the setting configured, and ignore the settings from the lower priority templates that have the same setting configured. Therefore, the values in Datacenter, efwOlab.chi, and Global Settings will not be applied to the firewall. Reference:
[Manage Templates and Template Stacks]
[Template Stack Configuration]
[Template Stack Priority]

In Palo Alto Networks firewalls, the processing of NAT rules occurs in a top-down fashion, similar to security policies. To exclude a specific IP address from a broader source NAT rule, a more specific NAT rule must be placed above the broader rule.
C . Place a more specific NAT rule above the broader one:
Create a source NAT rule (NAT-Rule-1) to translate the broader network range (10.0.0.0/23) with dynamic IP and port translation. This rule allows the majority of the subnet to access the internet through NAT.
Create another NAT rule (NAT-Rule-2) with the source IP address in the original packet set specifically to the IP address that should not be translated (10.0.0.10/32). In this rule, set the source translation to none, indicating that this traffic should not be translated and thus not allowed to access the internet.
Place NAT-Rule-2 above NAT-Rule-1 in the NAT policy list. This ensures that the more specific rule (NAT-Rule-2) is evaluated first. If traffic matches NAT-Rule-2, it will not be translated or allowed to the internet, effectively excluding the specific server from internet access.
This configuration leverages the principle of specificity and the order of operation in NAT policies to exclude a specific IP address from source NAT translation, thereby preventing it from accessing the internet.