1 Oct
2012
1 Oct
'12
3:33 a.m.
On Mon, 1 Oct 2012, James Harper <james.harper@bendigoit.com.au> wrote:
if you set the MTU to 9000, then you're telling Linux that packets up to that size are OK. it won't magically deduce that you really meant 1500 most of the time but sometimes 9000.
It makes perfect sense. Think of the physical interface as being separate from the eth0 interface, so eth0 is just another vlan:
Physical interface MTU = 9000 (>= largest VLAN MTU) eth0 (vlan1, untagged) MTU = 1500 eth0.12 (vlan12, tagged) MTU = 9000
Why does it have to be eth0 with an mtu of 1500? Why not call that eth0.1 and have the base eth0 not used for anything?
I've wondered that. Is eth0.1 (or can eth0.1 be) configured as an untagged interface and can see untagged packets? Thanks James