how to lan connection portal 2 console?

Answer 1

1) 1st thing you need to do is enable console on both PC's
2) on the 1st PC (Host) type sv_lan 1
3) on the 2nd PC type connect <PC1 Local IPAddress> (ie connect 192.168.1.10)
4) on the 1st PC (host) type map mp_coop_start

Thats all.

When a level finishes and loads the first level again just type in console: changelevel mp_coop_mapNameOfNextChapter (on PC1)

List of coop maps

"mp_coop_start" (First map of chapter 1)
"mp_coop_lobby_2"
"mp_coop_doors"
"mp_coop_race_2"
"mp_coop_laser_2"
"mp_coop_rat_maze"
"mp_coop_laser_crusher"
"mp_coop_teambts"

"mp_coop_fling_3" (First map of chapter 2, have to load this map after completing coop_teambts or else it will just restart coop_start)
"mp_coop_infinifling_train"
"mp_coop_come_along"
"mp_coop_fling_1"
"mp_coop_catapult_1"
"mp_coop_multifling_1"
"mp_coop_fling_crushers"
"mp_coop_fan"

"mp_coop_wall_intro" (First map of chapter 3)
"mp_coop_wall_2"
"mp_coop_catapult_wall_intro"
"mp_coop_wall_block"
"mp_coop_catapult_2"
"mp_coop_turret_walls"
"mp_coop_turret_ball"
"mp_coop_wall_5"

"mp_coop_tbeam_redirect" (First map of chapter 4)
"mp_coop_tbeam_drill"
"mp_coop_tbeam_catch_grind_1"
"mp_coop_tbeam_laser_1"
"mp_coop_tbeam_polarity"
"mp_coop_tbeam_polarity2"
"mp_coop_tbeam_polarity3"
"mp_coop_tbeam_maze"
"mp_coop_tbeam_end"

"mp_coop_paint_come_along" (First map of chapter 5)
"mp_coop_paint_redirect"
"mp_coop_paint_bridge"
"mp_coop_paint_walljumps"
"mp_coop_paint_speed_fling"
"mp_coop_paint_red_racer"
"mp_coop_paint_speed_catch"
"mp_coop_paint_longjump_intro"
"mp_coop_credits"

 

source:http://forums.steampowered.com/forums/showthread.php?t=1855538