Policy-Based Forwarding with dual ISP's

[Yusuf_PA]

Hi ALL,

We are planning to build active passive PA with 2 ISP's and want to send S2S VPN traffic through ISP1 and Internet traffic through ISP 2.

We are running static routing for both the ISP.Can someone suggest how to configure PBR in PA.

[SutareMayur · Accepted solution]

Hi @Yusuf_PA , If you want to route internet traffic via PBF, you can put PBF rule as follows -

Configure

1. Source and destination zones, Source IP address/subnet

2. Destination address would be any as it is internet traffic

3. services & apps according to your requirement (You can put any as well)

4. Under Forwarding, actions should be 'forward'

5. Select Egress interface from dropdown (Here select interface where ISP internet link is terminated)

6. Select Next Hop as 'IP Address' and define ISP gateway IP address. So once PBF is matched, that traffic will be forwarded to mentioned IP address.

Hope this helps you!

Mayur

[SutareMayur]

Hi @Yusuf_PA ,

Which traffic do you want to route via PBF?

If you want to route any of the traffic via PBF then you can put it by following way -

e.g. you want to route internet traffic via static routing and IPsec traffic via PBF then 

1. Keeping default static route for internet traffic going towards ISP2 default gateway.

2. Write PBF as follows,

Configure specific source, destination zones and source & destination ip addresses. Keep action as forward and point traffic to associated tunnel interface under egress interface.

Here keep next hop as 'none'

This will forward traffic of mentioned source and destination towards tunnel.

hope it works for you!

Mayur

[Yusuf_PA]

Thanks Mayur.

Can you tell me how to configure,If I want to route internet traffic via PFB.

[SutareMayur · Accepted solution]

Hi @Yusuf_PA , If you want to route internet traffic via PBF, you can put PBF rule as follows -

Configure

1. Source and destination zones, Source IP address/subnet

2. Destination address would be any as it is internet traffic

3. services & apps according to your requirement (You can put any as well)

4. Under Forwarding, actions should be 'forward'

5. Select Egress interface from dropdown (Here select interface where ISP internet link is terminated)

6. Select Next Hop as 'IP Address' and define ISP gateway IP address. So once PBF is matched, that traffic will be forwarded to mentioned IP address.

Hope this helps you!

Mayur

[sedelman0]

Mayur,

Whenever I use next hop as 'none' in policy based forwarding and in static routing and provide the egress interface only, traffic is never forwarded out the desired interface.  I have DHCP-assigned Internet WAN and cannot provide a consistent next hop so I was trying to rely on only the egress interface for forwarding.  Any suggestion on how to accomplish this configuration goal?

Thank you! -Shane

[SutareMayur]

@sedelman0 

If you are putting static route with only exist/egress interface and next hop as none, then it should work. The only condition here is Route will be inserted into FIB table when mentioned interface is up. So post configuring such static route, do you see any arp learning on the egress interface?

Please check.

Mayur

[sedelman0]

@SutareMayur 
Thank you so much for the reply, I really appreciate it.
Here is a simple configuration that demonstrates the issue:
-Static route with only egress interface added (does not work)
-Static route with egress interface and next hop IP address (works)
-Both have the next hop IP address in the arp cache

routing-table {
ip {
static-route {
test_1.1.1.1 {
path-monitor {
enable no;
failure-condition any;
hold-time 2;
}
bfd {
profile None;
}
interface ethernet1/2;
metric 10;
admin-dist 10;
destination 1.1.1.1/32;
route-table {
unicast;

routing-table {
ip {
static-route {
test_1.1.1.1 {
nexthop {
ip-address 73.196.120.1;
}
bfd {
profile None;
}
path-monitor {
enable no;
failure-condition any;
hold-time 2;
}
interface ethernet1/2;
metric 10;
admin-dist 10;
destination 1.1.1.1/32;
route-table {
unicast;

This unexpected functionality is the same with policy based routing as well.