Changing MTU size

Changing MTU size

Post by Rick Wals » Fri, 18 Mar 2005 02:55:42


Hi,

Has anyone successfully changed the MTU size to something larger than 1500
and run successfully? We have an application that needs to use an MTU of
16k over Gig-E. We're running QNX 6.3 on a x86 with a 82544 Enet chip.
We've tried changing the params via io-net/devn-i82544 but they don't seem
to take effect. The packets still seem to get fragmented into 1500 byte
chunks.

Thanks,
Rick
 
 
 

Changing MTU size

Post by Igor Koval » Fri, 18 Mar 2005 04:55:43

To do that your driver must support 'jumbo frames' feature. I doubt that QNX
driver does it, but 'check with your sales representative' ;)

 
 
 

Changing MTU size

Post by Armin Stei » Fri, 18 Mar 2005 05:55:39


Max size of JUMBO packets is 9018 bytes as specified in if_ether.h

Armin
 
 
 

Changing MTU size

Post by Rick Wals » Sat, 19 Mar 2005 03:55:43

Thanks for the tips. We've got to the point where QNX can send a jumbo
frame, but it can't receive one.





QNX


1500
of
seem