Load balancing of 2 internet connections

I am going to replace my current load balancer with a mikrotik 493ah. I have read the many post on load balancing, and want to know can I set the detect link down to something other than the default gateway and if so how to set this. My current issue, my def gw is the cable modem and while it may still be up, the actual internet to the cable modem is down. I need to be able to test to something out on the internet. Also how do I set say 75% traffic down one link and 25% down the other while both are up and then if one goes down 100% goes down the circiut that is still up? There will only be one network behind the router a /23 network, which I need for the mikrotik to hand out dhcp and nat. Thanks for any help on this.

Alan

Hi
2 way’s to do it will be a mix of ether nth + scrips or ecmp + scripts plz search the forum as it has bean cover ALLOT :wink: if you don’t come right let me know and I’ll give you an example I’m currently doing it with 7 links from ISP"S and it works great and I’m using a RB600 with A daughterboard for more Nic’s.

dear friend
i do it with 3 internet line
can i have your contact information for comparing my solution with your solution?