Yes, please read the documentation on how to enable IPTraffic.
Thanks Merlin!
I posted the documentation to save others from hunting for it.
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** Enhanced Traffic monitoring **
Under Tools -> Other Settings are options that will allow you to save
your traffic history to disk, preserving it between router reboots (by
default it is currently kept in RAM, so it will disappear when you
reboot).
You can save it to a custom location (for example, "/jffs/" if you have
jffs enabled), or /mnt/sda1/ if you have a USB disk plugged in.
Save frequency is also configurable - it is recommended to keep that
frequency lower (for example, once a day) if you are saving to jffs, to
reduce wearing out your flash memory. Make sure not to forget the
trailing slash ad the end of the path.
Note that the first time you use that option, you must tell the router
to create the data file. Make sure you set "Create or reset data
files" to "Yes".
Also, Asuswrt-Merlin can track the traffic generated by each individual
IP on your network. This option is called
IPTraffic. To enable this,
you must first set a custom location to store your traffic database
(see above). Once again, you must also tell it to create the new data
file, by enabling "Create or reset IPTraffic data files". Once done,
enable the IPTraffic Monitoring option. This will add three new
entries to the Traffic Monitor page selector (on the Traffic Monitoring
page).
You can optionally specify which IP to monitor, or exclude some IPs
from monitoring. Each IP must be separated by a comma.
