mtu speed

[kps gill]

how can i change the mtu speed of a particular lan card on my hp unix box

[spex]

Hello,

See my post here:
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1062605

# lanadmin -M

PCS

[Rasheed Tamton]

The above is the correct command to change the mtu speed.

If you want to see the current speed:
lanadmin -m 0

[skt_skt]

Are you using autoport aggregration among those lan cards

[Adisuria Wangsadinata_1]

Hi kps gill,

To check the present value of mtu on your lancard, you can use the command 'netstat -rn' and 'lanadmin -m Crd_In#' :

# lanscan
Hardware Station Crd Hdw Net-Interface NM MAC HP-DLPI DLPI
Path Address In# State NamePPA ID Type Support Mjr#
0/0/0/0 0x000F201D0ED6 0 UP lan0 snap0 1 ETHER Yes 119
0/2/0/0 0x00306EF4D4CD 2 UP lan2 snap2 2 ETHER Yes 119
0/4/0/0 0x00306EF4D4CF 3 UP lan3 snap3 3 ETHER Yes 119
# lanadmin -m 0
MTU Size = 1500
# lanadmin -m 2
MTU Size = 1500
# lanadmin -m 3
MTU Size = 1500
#

To change it, you can use the command 'lanadmin -M new_mtu_number Crd_In#'

NOTE : Crd_In# = PPA number

You can also take a look at this documentation (docID : WHALENKBRC00002499) at this url :

http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en&docId=emr_na-c01033481-1

Hope this information can help.

Cheers,
AW.

[rick jones]

What leads you to want to change the MTU of an interface? If you want to make it larger - in other words enable jumbo frames - you have to make sure that _everything_ in the same broadcast domain has jumbo frame support enabled.

If you want to make it smaller, it suggests that your network does not have functioning Path MTU discovery.