Jumbo frames on Cisco

For IOS:

3750(config)# system mtu jumbo 9000
3750(config)# exit
3750# reload

7609(config)#int gigabitEthernet 1/1
7609(config-if)#mtu ?
<1500-9216> MTU size in bytes

7609(config-if)#mtu 9216

Verify in Native IOS:

7609#show interfaces gigabitEthernet 1/1
GigabitEthernet1/1 is up, line protocol is up (connected)
Hardware is C6k 1000Mb 802.3, address is 0007.0d0e.640a (bia 0007.0d0e.640a)
MTU 9216 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255

For CatOS:

Cat6509> (enable) set port jumbo
Usage: set port jumbo <mod/port> <enable|disable>
Cat6509> (enable) set port jumbo 1/1 enable
Jumbo frames enabled on port 1/1.
Cat6509> (enable) 2002 May 29 12:34:35 %PAGP-5-PORTFROMSTP:
Port 1/1 left bridge port 1/1
2002 May 29 12:34:38 %PAGP-5-PORTTOSTP:Port 1/1 joined bridge port 1/1

Verify in CatOS

Cat6509> (enable) show port jumbo
Jumbo frames MTU size is 9216 bytes.
Jumbo frames enabled on port(s) 1/1,9/1.

Literature:
Cisco manual

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