> For the complete documentation index, see [llms.txt](https://ccie-sp.gitbook.io/ccie-spv5.1-labs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ccie-sp.gitbook.io/ccie-spv5.1-labs/labs/isis/default-route-preference.md).
# Default Route Preference
Load **isis.inter.area.cfg**
```
#IOS-XE
config replace flash:isis.inter.area.cfg
#IOS-XR
configure
load bootflash:isis.inter.area.cfg
commit replace
y
```
Configure area 49.1234 so that R2 prefers R3 for the default route, and only uses R4 upon loss of R3. Do not use metrics to achieve this.
## Answer
```
#R3
route-map SET_L1
set level level-1
!
router isis
default-information originate route-map SET_L1
```
## Explanation
ISIS allows us to originate a default route just like OSPF. An L1 router will prefer an explicit 0/0 route that is advertised in the area over using the ATT bit.
By default, when a router uses **default-information originate**, the default is only injected into L2. To set L1 only, or L1/L2, we must use a route-map.
```
#R3
route-map SET_L1
set level level-1
!
router isis
default-information originate route-map SET_L1
```
R2 now sees an explicit 0/0 route advertised from R3:
Due to this, R2 only uses R3 as its default route:
We can see the ISIS RIB still has both 0/0 routes generated from the ATT bit set on R3 and R4, but the explicit 0/0 is preferred and installed:
