TerraMaster Forum

Hi
I am seeing numerous console warnings that ethernet is in promiscuous mode.
I have bonded adaptive load balancing on 2 x 1Gb connections correctly established.
Only app installed is multimedia server, but it is not active.
No VPN, no remote access, no proxy - basically vanilla system.

Is this correct or a configuration error? My understanding is that promiscuous mode should normally be disabled.

Would you explain what is promiscuous mode? where is the warning sent from?
This is what I learn: https://www.techtarget.com/searchsecuri ... cuous-mode
but not sure what is the exactly your case.

Seems we know as much as each other

Quoting from the article:

What are the drawbacks of promiscuous mode?
Promiscuous mode is often used to monitor network activity and to diagnose connectivity issues. It is sometimes given to a network snoop server that captures and saves all packets for analysis, for example, to monitor network usage.

However, due to its ability to access all network traffic on a segment, this mode is considered unsafe.

The operative word being "unsafe"

The messages are appearing on the console [HDMI output to screen] and are not something I recall seeing before update to 5.1.37 and they are multiple outputs over time. I cannot readily identify any specific log available via GUI.

Messages:
[1549709.339954] r8152 5-2:1.0 eth1: Promiscuous mode enabled
[1550106.991451] ==ditto==
[1550107.123747] == ditto==
and so on
and so on
[The screen is full]

I presume the initial numbers are a time code and the messages are generated by the ethernet controller/adapter/kernel. Given the frequency I presume this is something the controller is "not particularly happy about". Without explanation, neither am I.

Thank you and I would be grateful for someone at @TMsupport, with networking knowledge, providing an answer. Why am I seeing this now and what
is the risk.

A means to turn off 'promiscuous mode' might also be useful. (I am ok with command line operation - been there, got the T-shirt!)

Thank you, our team will verify the issue and discuss your feedback and suggestions.

OK.

I believe this (eth1) is actually a built in USB/ethernet adapter. I notice others having issues with add-on usb/ethernet adapters on latest TOS versions?

Coincidence???

OK, I may have a clue .....

When promiscuous mode warnings were showing I had a USB drive plugged into one of the USB ports - but this was powered off (so just a 'dead' cable as seen by USB port). The other USB port has UPC plugged in (APC).

When I went to access the terminal (console) I unplugged the USB drive and plugged in keyboard. The promiscuous mode warnings have stopped (12 hours approx).

I will try and verify later.

Sorry, ignore my last post. Warnings are still present but less frequent. If I interrogate
the ethernet ports, they do not identify as being in promiscuous mode. Strange.