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Subject: Re: TCP problems
From: Dieter BSD <dieterbsd@gmail.com>
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Larry:
> Can you do a sysctl dump for each NIC to see their settings?

# sysctl -a | grep re0
dev.miibus.0.%parent: re0
dev.amdtemp.0.core0.sensor0: 16.2C
# sysctl -a | grep ue0
#

Hmmmm, 16.2 degrees C = 61.16 degrees F  Seems very unlikely.

Somehow I don't think this is what you had in mind?
ifconfig says:

re0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=82098<VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC,LINKSTATE>
        media: Ethernet autoselect (1000baseT <full-duplex>)

ue0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=80009<RXCSUM,VLAN_MTU,LINKSTATE>
        media: Ethernet 100baseTX <full-duplex>

> Keep in mind, if you are going through a switch, you may need to bump
> the switch's MTU too if you want to try jumbo frames. Are these machines
> direct connected?

G_re0  ----- Netgear GS116  --- Netgear GS108 --- T_bge0
                            --- A_tlp0  NetBSD/alpha tulip 10 Mbps

G_ue0  ----- Netgear GS108  --- T_nfe0

http://www.downloads.netgear.com/files/GDC/datasheet/en/GS116v2.pdf
doesn't seem to be sure about the MTU:
page 1 says  9 KB
page 2 says 16 KB

But ifconfig refuses to increase MTU for ue0, so...