Network troubles after 8.3 -> 8.4 upgrade

[Andrea Venturoli]

On 04/17/14 23:45, John Nielsen wrote:

Thanks for answering John.


> My first thought was TSO as well, since I've seen the symptoms you describe a few times on systems running 10.0.
 > Do you use IPFW or any kind of NAT on this system?

Yes, I use ipfw to firewall, to divert packets to natd and also to 
forward specific traffic to three different gateways.

I think I added a "10 allow ip from any to any" rule for a brief period 
of time to exclude ipfw's interference, but I'm not sure and eventually 
I'll try again next week.



> When an application encounters a network problem,
> does it report or log anything at all?

Simply a timeout.



> Anything in the kernel log/dmesg?

I wished so; unfortunately, as I wrote, unless there's some sysctl to 
tweak I get no suck info.



> Otherwise my only other thought would be the driver.
 > Can you try reverting only the em(4) driver back to 8.3?

Worth a try I guess!



 > Build modules and a kernel without em(4) from unmodified 8.4 src, 
load em(4) as a module,
 > confirm that the problem persists.

Ok, easy.



> Replace the contents of  src/sys/dev/e1000, src/sys/modules/em and
 > src/sys/conf/files with those from an 8.3 src tree (or otherwise
 > revert revision 247430), rebuild em module, unload/reload or reboot,
 > see if problem goes away. (Could be somewhat complicated by the fact
 > that you also have igb interfaces which also use code from the e1000
 > directory, but rather than speculate I'll leave solving that as an
 > exercise for someone else.)

Hmmm, sounds a bit complicated... would simply dropping if_em.ko in from 
a 8.3 box work?

  bye & Thanks
	av.