let us assume simple scheme with two routers, attached to a different isp and one lan with customers.
what we need to do to configuration at all.
exact config - at attached file.
Thanks in advance.
p.s. i forgot… it shuld be bgp configuration with one as
i looking for a guide. or tutorial. or wiki.
This is beyond the scope of a simple how to or configuration sample. You will probably need to hire a consultant to design this setup. We have something very similiar, two border routers, interconnected directly with the LAN behind it. It’s not a quick setup or howto : )
sure, it is not very simple stuff.
after issue completed, i’ll make a gift - posting all configs here.
and a bit more.
all consultans we use had never heart about mikrotik.
we have that configuration, but with cisco for all i know.
my idea is to organize and implement that model with mikrotik routers only. futhermore, network with mikrotik routers only. 
we plan to create small (500 customers there), span new network organization with: two border model introduced above; 100% pure mikrotik network - all routers MT boxes, no ciscos, no linuzes etc.
Sorry, i didn’t get the whole picture - where is the problem?
Do you have real IP addresses or do you use masquerade?
If real addresses - are you able to route them via both ISPs?
Do you need failover? What kind?
At this point it looks like standard routing with ECMP route on first router!
You can use 1 mt box for BGP with 1 ASN and more ISP.
You can use real IP for your client or nat.
#yes, we have real ip addresses
#yes, we able to route them via both isps
#we don’t like failover at this time
both routers have attached customers, not just one /as shown at the pic/.
1st MT box is attached @ isp1, 2nd - @ isp2. both routers have attached customers on it.