no ip domain-lookup command can use to advoid router to query the DNS that will waste the time to reset the connection
--------------------------------------------------------------------------------
switch(config)#username test password test
switch(config)#services password encryption
switch(config)#enable secret password
switch(config)#line vty 0 15
switch(config-line)#login local
switch(config-line)#privilege level 15
this example show the configuration of the username and password with encryption mode.
by login local and authenticated, it will straight login to level 15 which is switch#
------------------------------------------------------------------------------
VTP domain test
VTP password testing
VTP mode server
VTP mode client
VTP mode transparent
VTP version 2
VTP is to sync all the VLAN database from VTP server to client.
VTP transparent is useful for individual switch to configure own VLAN.
-----------------------------------------------------------------------
ertherchannel L2(switch to switch ) & L3(switch to server )
L2 - switch(config-if-range)#channel-group 1 mode desirable
L3 - switch(config)#interface port-channel 1
switch(config-if)#no switchport (turn off the switching port capaibility and assign IP address)
