is-is

If add some routes:

ip route 1.1.1.1/32 2.2.2.3
ip route 1.1.1.1/32 2.2.2.2
ip route 1.1.1.1/32 2.2.2.4

In config they sorted by gateway:

# do show running-config 
...
Current configuration:
!
frr version 8.1-dev
...
ip route 1.1.1.1/32 2.2.2.4
ip route 1.1.1.1/32 2.2.2.3
ip route 1.1.1.1/32 2.2.2.2

But when added ip route 1.1.1.1/32 2.2.2.1, he will adde