如何改virtual lan的mtu

[watermelonyu]

我的環境如下

要怎樣才能修改lan900的mtu size

有沒有正確的步驟

# lanscan

Hardware Station Crd Hdw Net-Interface NM MAC HP-DLPI DLPI

Path Address In# State NamePPA ID Type Support Mjr#

1/0/0/1/0 0x00306E4BBA55 0 UP lan0 snap0 1 ETHER Yes 119

LinkAgg0 0x00306EF25715 900 UP lan900 snap900 7 ETHER Yes 119

LinkAgg1 0x000000000000 901 DOWN lan901 snap901 8 ETHER Yes 119

LinkAgg2 0x000000000000 902 DOWN lan902 snap902 9 ETHER Yes 119

LinkAgg3 0x000000000000 903 DOWN lan903 snap903 10 ETHER Yes 119

LinkAgg4 0x000000000000 904 DOWN lan904 snap904 11 ETHER Yes 119



# netstat -rn

Routing tables

Destination Gateway Flags Refs Interface Pmtu

127.0.0.1 127.0.0.1 UH 0 lo0 4136

140.110.8.165 140.110.8.165 UH 0 lan900 4136

140.110.8.150 140.110.8.150 UH 0 lan0 4136

140.110.8.128 140.110.8.165 U 2 lan900 1500

140.110.8.128 140.110.8.150 U 2 lan0 1500

127.0.0.0 127.0.0.1 U 0 lo0 0

default 140.110.8.254 UG 0 lan900 0

[watermelonyu]

Good morning Joey :

I don't think the MTU size of APA link lan900 can be direct changed. The MTU size of APA link is inherent from the under layer link (real physical link). Depend on what type of physical link your used, some card's MTU can be changed, somre cards are not.



The -M option of lanadmin command can be used to change the MTU size.



The -m option of lanadmin command can be used to verify the MTU size.



On your environment, I think lan0 is the under layer of lan900. The PPA of lan0 is 0. The PPA of lan900 is 900. So, assume your link to change the MTU of lan900 to 1400, You can do it as follows,



1. Change the MTU of lan0 to 1400

# lanadmin -M 1400 0



2. check the mut size of lan0 and lan900

# lanadmin -m 0

# lanadmin -m 900



Hope this is help.

[watermelonyu]

One more thing, before the setp 1 on above, the apa subsystem should be stop first by

# /sbin/init.d/hpapa stop



after step 1, apa subsystem should be start by

# /sbin/init.d/hpapa start

[watermelonyu]

lan0 and lan900各有一組ip

lan900綁四張網卡(trunk),那這樣要怎樣才能改lan900

# ifconfig lan0

lan0: flags=1843 UP,BROADCAST,RUNNING,MULTICAST,CKO

inet 140.110.8.148 netmask ffffff80 broadcast 140.110.8.255

# ifconfig lan900

lan900: flags=1843 UP,BROADCAST,RUNNING,MULTICAST,CKO

inet 140.110.8.164 netmask ffffff80 broadcast 140.110.8.255

[watermelonyu]

假設 lan900 所綁網卡的 PPA 是 1,2,3 and 4



1. stop apa

# /sbin/init.d/hpapa stop



2. change MTU of lan1,lan2,lan3 and lan4

# lanadmin -M 1400 1

# lanadmin -M 1400 2

# lanadmin -M 1400 3

# lanadmin -M 1400 4



3. start apa

# /sbin/init.d/hpapa start



4. verify

# lanadmin -m 1

# lanadmin -m 2

# lanadmin -m 3

# lanadmin -m 4

# lanadmin -m 900





..

.