1st, The switch model and software
system: version 6.0(2)A1(1b)
cisco Nexus 3548 Chassis ("48x10GE Supervisor")
To enable jumbo frames you first need to build a policy. The name of the policy can be anything that you want it to be.
policy-map type network-qos jumboframes
class type network-qos class-default
mtu 9216
After you have defined the policy-map you can now activate it via the following ;
system qos
service-policy type network-qos jumboframes
To monitor the changes we issues the following commands ;
HETYSW2# show queuing interface ether 1/12 | grep MTU
HW MTU: 9216 (9216 configured)
HETYSW2#
We can also look at the interface counters, but I believe the switch doesn't report packets bigger than 1548 bytes;
e.g
show int eth 1/12 counters detailed
Ethernet1/12
Rx Packets: 99810475
Rx Unicast Packets: 99567164
Rx Multicast Packets: 244586
Rx Broadcast Packets: 108
Rx Bytes: 10238006362
Rx Packets from 0 to 64 bytes: 1111204
Rx Packets from 65 to 127 bytes: 75378834
Rx Packets from 128 to 255 bytes: 14313107
Rx Packets from 256 to 511 bytes: 2618278
Rx Packets from 512 to 1023 bytes: 2467560
Rx Packets from 1024 to 1518 bytes: 2493491
Rx Packets from 1519 to 1548 bytes: 1429384 <------HERE
Tx Packets: 116271700
Tx Unicast Packets: 115850055
Tx Multicast Packets: 421292
Tx Broadcast Packets: 353
Tx Bytes: 16564798171
Tx Packets from 0 to 64 bytes: 16577055
Tx Packets from 65 to 127 bytes: 68013570
Tx Packets from 128 to 255 bytes: 21122812
Tx Packets from 256 to 511 bytes: 3376787
Tx Packets from 512 to 1023 bytes: 3864588
Tx Packets from 1024 to 1518 bytes: 3295462
Tx Packets from 1519 to 1548 bytes: 21426 <------HERE
and
show int eth 1/12 counters errors
--------------------------------------------------------------------------------
Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize OutDiscards
--------------------------------------------------------------------------------
Eth1/12 0 0 0 0 0 0
--------------------------------------------------------------------------------
Port Single-Col Multi-Col Late-Col Exces-Col Carri-Sen Runts
--------------------------------------------------------------------------------
Eth1/12 0 0 0 0 0 0
--------------------------------------------------------------------------------
Port Giants SQETest-Err Deferred-Tx IntMacTx-Er IntMacRx-Er Symbol-Err
--------------------------------------------------------------------------------
Eth1/12 0 -- 0 0 0 0
Alternatively you can review the network-qos policy-map to confirm mtu sizes the default and current size are shown ;
show policy-map type network-qos
Type network-qos policy-maps
===============================
policy-map type network-qos jumboframes
class type network-qos class-default
mtu 9216
policy-map type network-qos default-nq-policy
class type network-qos class-default
mtu 1500
Ken Felix
Freelance Network / Security Engineer
kfelix ----a---t---socpuppets ---d---o---t---com
^ ^
=( ^ ^ )=
o
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Awesome,
ReplyDeleteAnd is this all? All my interfaces will be forwarding Jumboframes? My config is for a Storage and they need the half of the interfaces working without jumbframes.
This only enables the interface to accept jumbo frame.
ReplyDeleteYeap only the layer2 interface. If you have a SVI you still need to enable mtu setting and a lot of the non 7K still will not allow you to set the interface MTU.
ReplyDeletee.g
config t
int vlan 44
mtu 9126
end
Without the fabric being made aware of the jumbo frames, you can't run any SVIs at a larger ethernet frame.
how to you apply this on the interface? does it apply to ALL interfaces or is it 1x1? thx
ReplyDelete