I have a 3560G switch that all of our servers are plugged into. Most of the servers are HP DL380-G3 or G5's. Because of that i have the HP Network Config tool which allows me to set the MTU as well as do some nice LCAP etherchannel. I have the etherchannel channel working nicely on some test servers and i would like to try out the higher MTU and see performance gains if any. However i know that i need to set the system mtu, and cannot change per interface.
My question is that if I change the system mtu jumbo to 9000 will that break the servers that i haven't changed to the larger MTU? Likewise what about my switch to switch point-to-point links where i haven't changed the MTU on that switch yet.... I would rather not break anything, but at the same time want to only test with a small number of devices not everything at once.