Jumbo frame problem with ESXi 5.5 and vmxnet3 driver
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Well, new quirk.. If I try to set lower values on the GUI, the actually take properly.
So if I set the MTU to be 2000, it works.
If I set it to be 8000, it works.
If I set it to be 8999, it works.However, if I set it to be 9000, it won't take and the previous value is preserved.
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Well, nevermind that.. if I reboot then the MTU for the route goes back to 1500, yet the interface is set to 8000 (for example).
I give up. There's clearly something wrong, but I can't figure out what or how to fix it permanently.
I'll try again on a future release.
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before you were not even using vmx interface you were on em
interface: em1
So that would explain why no jumbo_mtu listed for the interface.
I have not had to reboot anything to get this working. You running 32 or 64 bit pfsense?
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It's 64 bit Pfsense. What could explain the behavior I saw where only the 9000 value for MTU won't take? Any other value works.. at least until I reboot, and then it doesn't.
In all cases the MTU is set on the interface, but the routes are not flagged with the appropriate MTU when it's set to 9000 or after rebooting if set to another value.
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I think there are multiple issues at play here. FreeBSD 8.3 has issues in not updating the MTU on routes in jumbo frame scenarios at times, potentially both for the link routes and any associated static routes. Scripting a "route change x.x.x.x/x -mtu 9000" at boot time for all required routes is a suitable workaround where you encounter that and the NIC driver properly handles jumbo frames. vmxnet on 8.3 just doesn't work with jumbo frames from what I've seen. Similar for Broadcom NICs, though those are very reliable and well-performing NICs, in 8.3 they don't work with jumbo frames (an oddity of the hardware that wasn't properly accommodated in the driver at that time, it's since been fixed). These issues have all already been confirmed fixed in FreeBSD 10 and hence 2.2.
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"vmxnet on 8.3 just doesn't work with jumbo frames"
Looks to be working to me - what driver did you test with? I don't really see a need for jumbo in my home network. It would just complicate the connections and not all devices support them. I could always segment out even more and put my non jumbo on their own segment, etc. Seems kind of pointless for what I am doing.
As you can see from thread I was able to ping at the full mtu - but be happy to do some other testing to validate its working.
