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In this menu, you can tweak some secondary, less critical settings. These settings rarely need to be modified. If you change them, make sure you understand the consequences of those changes.
Boot Wait Time * : the time period during which you can access the router via its CFE webserver.
This refers to the bootstrapping portion of the process, or the loading of code before the OS loads. If you need to delay the boot process (to stay in internal webserver CFE mode), change this setting.
In rare circumstances, such as a power outage, your modem might take longer to boot than FreshTomato does. This setting could be used to tune that until it is optimal. The asterisk (*) indicates not all hardware models support this feature.
WAN Port Speed: lets you set the WAN port to Autonegotiate mode or force a specific speed/duplex combination for it.
Only 10Mbps and 100Mbps speeds can be forced. For 1Gpbs, leave it at Autonegotiate. Not all models support this feature.
(Default: Autonegotiate).
CTF (Cut-Through Forwarding): if checked, enables Level 1 NAT hardware acceleration.
CTF lets bridges use an alternative forwarding method for storing/forwarding frames. Enabling it may improve speeds on Internet plans with a profile above 100 Mb/second. CTF is usually necessary to reach peak speeds on plans that allow 200 Megabits/second and higher.
With CTF enabled, the router starts to send transmission frames as soon as the full packet header has been received. However, it relies on the client to tell it whether the data is corrupted for resend. This restriction can cause problems with a few common home uses.
Enabling CTF disables QoS and Bandwidth Limiter. It can also cause issues for IPv6 tunnelling protocols, like 6in4 Static. This is because the switching part of the packet bypasses parts of the standard Linux iptables chains.
With CTF disabled, the router stores the entire frame before sending it out to its destination.
When this happens:
CTF/FastNAT is supported as follows:
FastNAT is a similar function that forwards frames at accelerated speeds.
On ARM devices, you can expect performance in the range of 200 to 400 Mb/s with CTF enabled.
Enable Jumbo Frames: lets you increase the maximum frame size on the LAN. (Default: Disabled).
The default Jumbo Frames size is 2 KBytes. If enabled, Jumbo Frame capability will be enabled on all LAN/WAN ports.
This feature is supported only in 1000 Mb/s mode. Also, gigabit switches use more memory when this feature is enabled. This can affect performance, depending on how many switch ports simultaneously use jumbo frames. Not all hardware models support this feature.
Jumbo Frame Size: If enabled, this value overrides default frame size.
If disabled, default frame size is 2 KB. (Default: off). Generally, enable Jumbo Frames if you frequently transfer large files within your LAN. To function, all devices must support Jumbo Frames. You should also standardise the packet size across all LAN devices.
It is best to leave this disabled unless you have specific requirements for it. Using Jumbo Frames means Internet traffic will be fragmented, unless the end device supports Path MTU Discovery. Often, the limited performance benefits of Jumbo Frames isn't worth the time and effort needed to tune/troubleshoot it.
Not all hardware models support this feature.
Port Health: Since release 2025.5 a “port health” mechanism has been introduced. This is a watchdog counting errors on physical connections (Ethernet) and taking a defined action when an exception is spotted. This function was introduced to prevent a bad Ethernet cable to take your router down (eating up CPU cycles) and making the device unresponsive.
Enable - Runs the porthealth process to monitor the defined ports scope, every minute. The check is extremely lightweight and executes in about 0.02 ~ 0.04 seconds.
Mode - determines the script’s level of intervention when it detects network errors (a “flood”). It essentially sets the “remedy” strategy for a port that is currently exceeding your defined error threshold.
BASE_RATE), the script immediately shuts the port down using robocfg. Thsi approach protects the rest of the network or a background compilation process from being affected by a “chatty” or failing hardware interface. It forces manual intervention to re-enable the port.Ports - Defined the type of logical ports to be monitored so LAN only, WAN only or LAN + WAN.
Max Errors / Minute - A.k.a. Threshold. The number of acceptable errors per minute before an action (defined under Mode) is triggered. Under normal circumstances you'd expect the number of errors to be precisely 0; however in certain cases a little tolerance to deal with temporary situations like interferences, usual temperature, etc might be advisable.
Hold Time - Acts as “cool-down” and “efficiency” filters to prevent the script from making erratic or unnecessary changes to your network ports. A “calm” decision-making in this context is positive. When a port shows errors, the script steps down the link speed (e.g., from 1000FD to 100FD). The Hold Time ensures the system stays at that new speed long enough to actually see if the errors stop. If the script runs again before the 180 seconds (default) have passed, it will skip further down-stepping for that specific port, giving the hardware time to stabilise.
Cache TTL - Identify what ports are active is a bigger job than scanning them individually for errors. In this sense the Cache TTL defined how often the script performs the “heavy lifting” of scanning your router's hardware to spot see which ports are active. The script saves the list of active ports to a file in /tmp. It will reuse that list (only) for 1800 seconds (30 minutes) by default. It only re-scans the hardware if the cache file is older than the TTL or if the file is missing. This parameter doesn't affect the ultra-light scan for errors on active ports, happening every minute.