Someone recomanded for us to set weight on the bgp sessions so we do set weight 100 on all ISP sessions, the think i dont understand is if on one isp bgp session we set weight 101 the entire OUT Traffic drops on all ISP and it go true the session we set 101 not the input just the OUT, and we dont understand why all the OUT traffic and not just like X% of it.
One more think i dont understand is the way traffic is routed for example on mtr.
US > ISP 1 > TARGET ( 8 Hops ) 14ms. (We disable ISP 1)
US > ISP 2 > TARGET ( 4 Hops ) 6ms. (With ISP 1 Disabled)
When ISP 1 and ISP 2 is online i dont understand why he dosent chose ISP 2 ? It has only 4hops and 6ms direct pering with the target.