Ubuntu guest KVM stuck on Gbit.


New Member
Apr 21, 2015
I have running an Ubuntu KVM. It is going to be used as an Asterisk server and therefore has two interfaces so as to route SIP traffic over a seperate interface to a seperate network.
They both work, but on the second interface i'm troubleshooting a packetloss issue. When looking at the interface with ethtool it reports it has an 1000mbit uplink to the switch.
The switch it is connected to is in fact 100mbit (dumb/non-managed), so i'm trying to change the duplex setting of said interface on the server end to 100mbit full without autonegotion. (ethtool -s eth1 speed 100 duplex full autoneg off)
This command indeed turns off the auto negotiation but seemingly does nothing with the Link speed. On the host I use the e1000 option as a network device.
What could I be missing?


The host server this KVM runs on did in fact negotiate 100mbit.
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