Hi,
do you mean a primary/ backup scenario where when one ISP link is down then you still can access your server via the other ISP link? Are the 2 links on same router? if so then you can do this:
1) 2 static PAT entries for the server, one going to ISP1 interface ip address and the other to ISP2 interface ip address
2) 2 default static routes: one with AD of 1(default) for primary link and the other with a higher AD(floating route)
3) on the first route via primary track an IP SLA object.
if the links are on 2 routers then you can use HSRP with SNAT.
if you want a config snippet I'll post one for the 2 options.
Regards.
Alain.
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