VOSS static route overide

[treese]

I have fabric extend to a remote branch with the remote site learning the quad zero ISP default route from the far end location.  I setup a static route at the branch end so local users can use the local ISP default route.  I have a route-map built so the local default route won't get advertised/redistributed into ISIS.  

Here is the problem i'm trying to solve now.  If/when the local ISP goes down, I'd like the alternative route (quad zero router from far end) working so the local users will have internet access via the fabric.  The current solution to fix this is to remove the static route then the alternative routes pick up.  

Thanks for your help

show ip route alternative
DST MASK NEXT VRF/ISID COST FACE PROT AGE TYPE PRF
----------------------------------------------------------------------------------------------------------
0.0.0.0 0.0.0.0 10.x.x.x GlobalRouter                10           353 STAT 0 IB 5
0.0.0.0 0.0.0.0 DCxxxxx-SW01 GlobalRouter 20040 4051 ISIS 0 IASE 7
0.0.0.0 0.0.0.0 DCxxxxx-SW02 GlobalRouter 20040 4051 ISIS 0 IASE 7

[WillyHe]

Depending on the setup, which is not clear.

• Is there only one FE switch in the remote Branch?
• Is the local static default route directly to the ISP router or to another internal L3 switch?
• Is the ISP router directly connected to the FE switch?

There are several possibilities/solutions, some described below

When the local static default route is directly to the ISP router, then there are two possibilities.

• When the IP address of ISP router becomes unreachable then it will become unreachable after the default ARP time-out six hours and the MAIN site branch default route become active.
  Optionally the ARP table aging timer can be changed to a low(er) value (e.g. 5 minutes) on the FE switch, be aware this is a global setting on the device.
• When the ISP router is directly connected to the FE switch, two options
  1. When the link goes down then the MAIN site branch default route become active immediately because the ISP router is cleared from the ARP table.
  2. When the ISP router becomes unreachable, then again the ISP ARP entry must time-out.

When there is an internal L3 network between the FE switch and the ISP router,  then if a dynamic routing protocol is used in the internal network, the FE switch can be configured to be a member of the internal routing and receives the default route to the ISP which must have a lower cost than the default route from the MAIN branch, then the fail-over depends on the internal network.

[EF]

Sorry I dont understand/know concept of " local non static route".

A local route is a attached interface, for example a VLAN interface:

I don't understand how can you replace the static default route using this. 

[EF]

I think you should are able to reach the mgmt IP of your VOSS throught the FE, your data plain must be diferent from your control plane but I dont have details about your topo.

About the script, sorry, Im not auth to share this info, but keep it mind it´s possible, one more option.

[treese]

I understand, are you familiar with setting up a local non static route?  If I can do this in my lab, i'll remove the static route and have a local route then when it disappears it would hit on the fabric learned route.