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What can I use to accomplish this setup - 2 t1, 2 isp, and a switch with VLANs


I have a T1 at location A, and a T1 at location B. Location A and B are approx 50 miles apart. A and B have different providers. The routers at both location A and B are controlled by their respective Provider.

(Connecting them is a distributed wireless switch. This switch acts like any other switch. Users connect wirelessly, and based on the SSID, they are put on a VLAN. One physical port of the wireless switch terminates as ethernet at location A with untagged VLAN A, tagged VLAN B, another physical port of the wireless switch terminates as ethernet at location B with untagged VLAN B, tagged VLAN A)

So, in essence, it is a REALLY BIG LAYER 2 switch that supports VLAN, tagging, trunking etc.

I want to have this work as such:
People connected to VLAN A will be on the same network as location A, and they will use the router for Provider A to get out to the internet.
People connected to VLAN B will be on the same network as location B, and they will use the router for Provider B to get out to the internet.
This part is easy to setup, just like having them physically plugged into a vlanned switch.

BUT, when either T1 goes down, I need to have the traffic go out the other T1.

What would I need at Location A and Location B?

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1 Solution
Aaron StreetInfrastructure ManagerCommented:
set up hsrp or some other spare router protocal.

with hsrp you set up a virtual ip address that is shared by two routers (or more)

so say router a has an IP address of and Router B has an ip of  

then you set up the virtual IP to be and this is the default gate way that the clients see.

now one of the routers will be primary and reciving the requests from the clients, if this goes down, or the link drops, the other router takes over,

now you can set up mutiply virtual ips for each router.

so you would have

Router A
Router B

HSRP IP  (clients default gate way address)

then make Router A the primary for the address and router B Primary from the address.

now if either router fails the Default gateway IP address will be picked up by the other router and carry on forwarding the packets.

What routers / switchs do you have in place  at the T1 locations. if they are Cisco I can type out the commands to set this up.  

owner66Author Commented:
The equipment onsite are watchguard firewalls, t1 into WAN port, dumb switches on the LAN side.
So lets say that I got rid of the watchguards, and could add some routers.
What would the cisco config look like?
I would have i guess 2 virtual interfaces, and 2 vlan coming into the LAN ports on each router?
And, is this possible with watchguard (latest os)?

Aaron StreetInfrastructure ManagerCommented:

Route A

if#standby 1 ip
if#standby 1 priority 100
if#standby 1 preempt

if#standby 2 ip
if#standby 2 priority 90
if#standby 2 preempt

Route B

if#standby 1 ip
if#standby 1 priority 90
if#standby 1 preempt

if#standby 2 ip
if#standby 2 priority 100
if#standby 2 preempt

this sets up two stand by groups (1 and 2) in group 1 router A is the primary and in group 2 B is the primary (highest priority wins)

the preempt command makes sure that after a router that has failed comes back up, it retake the virtual Address back if it is the primary router.

you can also use the

#standby 1 track gigabitEthernet 1/1 20

 if you assume the WAN link is attached to gig 1/1 then if this port goes down, it will lower the pirority by 20. meaning that the back up router will become the active router and continue forwarding the traffic.

you can set the stand by ip address on subinterfaces of the router and have each one is its own vlan.

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