Question about configuring Jumbo Frames w/ Servers using Broadcom NICs

[osmhquser]

I have a questions regarding Jumbo Frame configuration. We have (2) 3750X switches in a stack configuration with Dell Equallogic 6500 storage and Dell Blades 610. The servers have Broadcom NICs with the Advanced Control Suite installed.

What should the following options be configured as on the Broadcom NICs that are attached to the switches:

Chassis PHY Flow Control (Options avaiable: Tx Enabed, Rx Enabled, Rx & Tx Enabled, Auto). Currently set to Rx & Tx Enabled.
Chassis SW Flow Control (Options avaiable: Tx Enabed, Rx Enabled, Rx & Tx Enabled, Auto). Currently set to Rx & Tx Enabled.
Jumbo Packet - Currently set to 8500 (I was told by one techician to set this to 8500 due to overhead). Is this correct or should it be set to 9000.

Is there any other configuration that needs to applied to our interfaces for jumbo support? (Jumbo support was enabled at the global level)

int g1/0/1
switchport access vlan 23
switchport mode access
switchport nonegotiate
flowcontrol receive desired
no cdp enable
spanning-tree portfast

Thx in advance for any assistance provided.

[s.kanth]

Hi

MTU size would be 9216 for jumbo frames . you can use below configuration to enble jumbo frame on Nexus.

Jumbo frame configuration.

switch(config)#policy-map type network-qos jumbo

switch(config-pmap-nq)#class type network-qos class-default

switch(config-pmap-c-nq)#mtu 9216

switch(config-pmap-c-nq)#exit

switch(config-pmap-nq)#exit

switch(config)#system qos

switch(config-sys-qos)#service-policy type network-qos jumbo

It is the global configuration on Nexus switch, we can't enable it on interface level.

Thanks

Sri