iSCSI cannot listen below TCP port 1025

TrueNAS General
1

Hello,

I upgraded from CORE to SCALE and the iSCSI service could not be condigured to use port 860 as configured before. I have an error about ports below 1025 being forbidden.

I tried a workaround by launching socat TCP4-LISTEN:860,bind=0.0.0.0,reuseaddr,fork TCP4:127.0.0.1:3260 at boot to redirect all traffic from iscsi clients on port 860 to 3260.
However it did not work as expected as discovery returned no portal found.

The working solution I found is to launch the following script at boot:

echo 'ISCSID_OPTIONS="-p 860"' >/etc/scst.env
chattr +i /etc/scst.env

However, I’m wondering what is the limitation keeping iscsi from listening on port 860?

Thank you