How to set X710/XL710/X722 SFP Port Tx disable function

Purpose:

It list How to enable X710/X710/X722 SFP TX_disabled function by Linux i40e driver for customer reference, 

Target Audience:

For Advantech TSE, RBU AE, outsourcing service engineer(s) and End customer with the following knowledges  :

• Linux and Ethernet  troubleshooting experience

Content:

1. TX disable function means SFP module's TX port to disable laser signal after key-in "ifconfig down"

2. Some user monitors remote system's link status by Switch, when remote system 10 Gb port (X710/XL710/X722) & SFP module don't support  Tx disable,  the switch side always keep remote system Link status as ON after remote system side key-in ifconfig <NIC> down.

2.By Intel default setting, the X710/XL710/X722 network Link/speed LED always keep turn on after key-in ifconfig <NIC ID> down.

3. When remote system's needs to enable X710/XL710/X722 Tx disable function, it has to check following items.

3.1 SFP module needs to support TX disable, 

3.2 X710/XL710/X722 NIC needs to key-in following command  for set "link-down-on-close" as ON

# ethtool --set-priv-flags <NIC ID> link-down-on-close on
# ethtool --show-priv-flags <NIC ID>
# ifconfig <NIC ID> down

PS: The priv-flags setting will return to default after reboot or power-off system, suggesting customer makes a script to set priv-flags function.

4. Example: Set NMC-1011 port 1  to enable TX disable

4.1 Key-in following command to set NMC-1011 port 1 (NIC ID: b17p0)  to enable TX disable

# ethtool --set-priv-flags b17p0 link-down-on-close on
# ethtool --show-priv-flags b17p0
Private flags for b17p0:
MFP                    : off
LinkPolling            : off
flow-director-atr      : on
veb-stats              : off
hw-atr-eviction        : off
link-down-on-close     : on
disable-source-pruning : off
disable-fw-lldp        : off
vf-true-promisc-support: off

4.2 key-in ifconfig <NIC ID> down command to set NMC-1011 port 1(NIC ID: b17p0) as down and check SFP module TX ports doesn't output signal.

# ifconfig b17p0 down
[ 1818.731818] i40e 0000:17:00.0 b17p0: NIC Link is Down

Root cause:

A. By Intel i40e Driver setting 

A1. The phenomenon seems Intel Driver Limitation, when user needs to turn off X710/XL710 LED function after key-in “ifconfig ethX down”, Please look following readme link and refer readme command to set  link-down-on-close Private Flag as on

https://downloadmirror.intel.com/24411/eng/readme.txt

Setting the link-down-on-close Private Flag

-------------------------------------------

When the link-down-on-close private flag is set to "on", the port's link will

go down when the interface is brought down using the ifconfig ethX down command.

Use ethtool to view and set link-down-on-close, as follows:

  ethtool --show-priv-flags ethX

  ethtool --set-priv-flags ethX link-down-on-close [on|off]

B1. Following SFP modules are support TX disable,

1G SFP modules

1G SFP	Vendor	Model name	Ethtool TX_disable test
	Formdfica	TSD-S1CH1-C11	Pass

10G SFP modules

10G SFP +	Vendor	Model name	X710 TX_disable test (Need ethtool setting)
	Eoptolink	EOLP-8596-02	Pass
		EOLP-8596-02-EOP	Pass
	Formerica	TAS-A1NH1-P011	Pass
	Color chip	CTS100SRCS1CC	Pass
	AVAGO	AFBR-709SMZ-IB2	Pass

40G SFP module

40G QSFP	Vendor	Model name	Ethtool TX_disable test (needs ethtool setting)
	Formdfica	TQS-Q1L59-882	Pass