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We are building some firewalls that run PFSense. The systems use the SuperMicro Super X8DTN+ motherboard, which includes a dual link intel gigabit network card (Intel 82576 controller)

I have tried this out on several different identical boxes -- always the same result.

Anyway, if I configure PFSense to use the IGB driver for the intel 82576 and I setup one port of the dual port controller to be WAN and the other to be LAN I get terribly slow speeds (about 10 kB/sec). This with wan=igb0, lan=igb1

If I add an additional, separate PCI-X network card (using the EM driver) i get phenomenal speeds (wan=em0, lan=igb0). Kicker is -- the igb driver is still in use!

Any ideas why this might be or how to go about fixing it?

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Which version of PFSense? 1.2.x? Or the 2.0 Beta? – Mark Henderson Feb 16 '10 at 23:16
The version we are using is 1.2.3 – SvrGuy Feb 17 '10 at 3:16
up vote 3 down vote accepted

It turns out that there is a bug in the IGB driver as it relates to Large Receive Offloading (LRO).

Disabling LRO fixes the above described issue.


echo "dev.igb.0.enable_lro=0" >>/etc/sysctl.conf echo "dev.igb.1.enable_lro=0" >>/etc/sysctl.conf

And reboot.

Everything works fine thereafter.

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