Ring parameter information

Ring parameter information

[Hosam Hittini]

Hi,

I have two network interfaces and I used "ethtool -g" to get their ring parameters, but I don’t quite understand the output
For the ethernet interface the output says the operation is not supported
For the wireless interface the output says the sending and receiving buffer sizes are equal to zero
I wonder if anyone can help me with that

hosam@Robin-01:~$ sudo ethtool -g eth0
Ring parameters for eth0:
Cannot get device ring settings: Operation not supported

hosam@Robin-01:~$ sudo ethtool -g wlan1
Ring parameters for wlan1:
Pre-set maximums:
RX:			0
RX Mini:		0
RX Jumbo:	0
TX:			0
Current hardware settings:
RX:			0
RX Mini:		0
RX Jumbo:	0
TX:			0

Regards,
Eng. Hosam Hittini

Re: Ring parameter information

[Rick Jones]

On 09/14/2014 11:14 PM, Hosam Hittini wrote:
> Hi,
>
> I have two network interfaces and I used "ethtool -g" to get their ring parameters, but I don’t quite understand the output
> For the ethernet interface the output says the operation is not supported
> For the wireless interface the output says the sending and receiving buffer sizes are equal to zero
> I wonder if anyone can help me with that
>
> hosam@Robin-01:~$ sudo ethtool -g eth0
> Ring parameters for eth0:
> Cannot get device ring settings: Operation not supported

That means what it says - the driver/device for eth0 does not support 
reporting ring settings.

> hosam@Robin-01:~$ sudo ethtool -g wlan1
> Ring parameters for wlan1:
> Pre-set maximums:
> RX:			0
> RX Mini:		0
> RX Jumbo:	0
> TX:			0
> Current hardware settings:
> RX:			0
> RX Mini:		0
> RX Jumbo:	0
> TX:			0

I am just guessing, but I would guess one of two things - either that 
driver doesn't "really" support retrieving ring settings, or there is a 
bug or no way for it to report them in a meaningful way.  You should 
look-up the driver name (ethtool -i) and then go to a kernel source tree 
and find that driver under drivers/net/ and see what its ethtool support 
code looks like.

rick jones