What is NAT pool exhaustion?

What is NAT pool exhaustion?

The NAT 44 pool exhaustion alert feature enables generation of alerts before addresses in an address pool are exhausted. This feature can help the administrator take action before the address pool is exhausted.

How does NAT pool work?

A NAT pool is a set of IP addresses that you can define and use for address translation. NAT policies perform address translation by translating internal IP addresses to the addresses in these pools.

What is a pat pool?

Port Address Translation (PAT), is an extension to network address translation (NAT) that permits multiple devices on a local area network (LAN) to be mapped to a single public IP address. The goal of PAT is to conserve IP addresses.

What is dynamic Pat hide?

Dynamic PAT (Port Address Translation), HIDE NAT and NAT Overload all refer to the same meaning – which is to dynamically NAT your internal network address segment to one IP address.

How do you determine whether a NAT port is exhausted on a FortiGate?

Solution

1. Ensure the necessary logging is enabled. Check that the default setting on the FortiGate GUI in Log&Report>Local Logging & Archiving, logging to memory is activated.
2. The following message will display when the NAT port is exhausted:
3. Use FortiOS 4.0 MR2 Patch 2 and above for the best optimization of this log:

What is Port Exhaustion?

Port exhaustion occurs when a node runs out of available ports. When an application stops using a specific port, the port enters a “time-wait state” before it becomes available for use by another application.

What is Fortigate session clash?

Session clash messages appear in the logs when a new session is created but a conflicting similar session already exists. When session clash happens, the old session will be closed and replaced by the new one. The only consequence is that it may cause some re transmissions. Solution.

How do you deal with port exhaustion?

If you suspect that the machine is in a state of port exhaustion: Try making an outbound connection. From the server/machine, access a remote share or try an RDP to another server or telnet to a server on a port. If the outbound connection fails for all of these, go to the next step.

How do I find my port exhaustion?

How Can I Find Out What Application Is Using Up My Client Ports?

1. Click on the Network Tab, then select the listening ports.
2. Sort the ports in ascending order to show lowest to greatest port numbers.
3. Scroll to the largest number, if it is 65535, then port exhaustion is occurring.