Hi what you want to acheive is quite very simple and often used by everyone.
here is a simple example for you typed on a real EX switch:
let say i want to copy port ge-0/0/7 configuration on port ge-0/0/8:
Alain@EX3200_Ala# show interfaces ge-0/0/7
unit 0 {
family ethernet-switching {
port-mode trunk;
vlan {
members [ red blue green ];
}
}
}
Alain@EX3200_Ala# edit interfaces ge-0/0/8
[edit interfaces ge-0/0/8]
Alain@EX3200_Ala#
edit interfaces ge-0/0/8 [edit interfaces ge-0/0/8]
user@EX3200# show
unit 0 {
family ethernet-switching;
}
[edit interfaces ge-0/0/8]
user@EX3200# load merge terminal relative
[Type ^D at a new line to end input]
unit 0 {
family ethernet-switching {
port-mode trunk;
vlan {
members [ red blue green ];
}
}
}
copy paste the red lines from the other ports and then type ctrl D
load complete
[edit interfaces ge-0/0/8]
user@EX3200# show
unit 0 {
family ethernet-switching {
port-mode trunk;
vlan {
members [ red blue green ];
}
}
}
Here it's done.
If this don't work for you i think you're doing something wrong, perhaps your terminal emulator is configured the wrong way, try to use htperterminal with the default config on the console port with just the seed modified.
Try also to have a look at the online trainings that are on the juniper web site or at the several books you can find for free
Hope this will help you