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Beginner
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Recieve traffic on fiber-card with RX only?

Hi,

I have some servers with Intel 82599ES 10-Gigabit SFI/SFP+ nics, and the SFP+ modules are Intel 10Gig LR (10GSFPLR). These are connected to some fiber-taps, with a single fiber-cable (since the taps are only sending traffic).

This means that we do not get a link on the nic. But will we be able to see the traffic on the nic, using promisc mode in Linux?

I have of course tried the ethtool, but it does not seem to work, despite no warning or error messages. Is it at all possible to force the speed of the nic, without link (and auto-negotiation)?

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Community Manager
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Hi Sitron_NO,

 

 

Thank you for posting at Wired Communities. To better check on this, can you provide further information below:

 

1) There are two ports on the E10GSFPLR module, are you saying you only connect the cable to one port on the module?

 

2) What is the fiber tap device you mentioned here?

 

 

Thanks,

 

sharon
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Beginner
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Hi,

1) There are two ports on the E10GSFPLR module, are you saying you only connect the cable to one port on the module?

Yes, the module has to two ports, one TX and one RX. Since the card shall only receive the traffic (and the tap are only sending traffic), the one single fiber are connected to the RX-port on the module.

2) What is the fiber tap device you mentioned here?

The make and model is a https://www.cbnetworks.fr/produit/TG_CO-OCUxxxx.pdf Transmode CO-OCU9010. Before it was connected to our new nic, it was attached to an appliance, which were able to receive traffic.

Regards,

Sitron_NO

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Community Manager
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Hi Sitron_No,

 

 

Thank you for the information. I will check on this.

 

 

regards,

 

sharon

 

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Community Manager
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Hi Sitron_No,

 

 

Further checking, our fiber optic Ethernet Adapters requires both RX and TX port connected in order to work. Hope this clarifies.

 

 

Thanks,

 

sharon
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Community Manager
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Hi Sitron_No,

 

 

Please feel free to update me if further assistance needed. Thank you.

 

 

Thanks,

 

Sharon
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Beginner
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Further checking, our fiber optic Ethernet Adapters requires both RX and TX port connected in order to work. Hope this clarifies.

Hi, and thanks for the reply. This is a requirement even when the Ethernet Adapter is set in promiscuous mode (only listen/receive traffic)? Is there no way to force the Ethernet Adapter to receive the traffic even if there is not link nor TX present?

Regards,

 

Sitron_NO
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Community Manager
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Hi Sitron_No,

 

 

Thank you for the reply. Let me further check.

 

 

Regards,

 

Sharon
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Highlighted
Community Manager
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Hi Sitron_No,

 

 

Further checking, TX and RX are both required on our NIC. Please feel free to update me if further assistance needed.

 

 

Thanks,

 

Sharon
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Highlighted
Community Manager
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Hi Sitron_No,

 

 

Please feel free to update me if further assistance needed. Thanks.

 

 

Regards,

 

Sharon

 

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