Junos Asymmetric Routing
fw at deneb.enyo.de
Fri May 28 16:27:28 CDT 2010
* Ken Gilmour:
> ISP1 is the default gateway, ISP2 is a backup provider but which is always
> active. Client comes in on ISP1's link, traffic goes back out on ISP1s link.
> Client comes in on ISP2's link (non default gateway) but for some reason,
> the packets seem to be going back out through the link for ISP1.
You cannot use Juniper's software forwarding platforms in this
scenario. This may sound like a drastic verdict, but I think it's a
pretty accurate summary of the situation.
Perhaps you can coax the software forwarding platforms into packet
mode (instead of flow mode), but from the documentation, I get the
feeling that Juniper doesn't want you to do that (at least on
J-series). You also lose some functionality if you do that. Moving
the filters to a different box doesn't help, either.
So you either have to buy real Juniper routers (and the necessary
service modules to implement this), or switch vendors.
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