Tricks: Maximum Recursive Route Lookups IOS vs IOS XR

Just small note, primarily for myself because long time ago I was absolutely sure that maximum recursive route lookup was limited to 3rd level depth (Maybe it was changed?), actually, for IOS 15.4(2)T1 tested that 9th lookup is too many:

Check it your own if you want ;)

192.168.0.0/24 - connected network in my example:

ip route 1.1.1.1 255.255.255.255 1.1.1.2
ip route 1.1.1.2 255.255.255.255 1.1.1.3
ip route 1.1.1.3 255.255.255.255 1.1.1.4
ip route 1.1.1.4 255.255.255.255 1.1.1.5
ip route 1.1.1.5 255.255.255.255 1.1.1.6
ip route 1.1.1.6 255.255.255.255 1.1.1.7
ip route 1.1.1.7 255.255.255.255 192.168.0.2


1.1.1.1/32, epoch 0
  recursive via 1.1.1.2
    recursive via 1.1.1.3
      recursive via 1.1.1.4
        recursive via 1.1.1.5
          recursive via 1.1.1.6
            recursive via 1.1.1.7
              recursive via 192.168.0.2
                recursive via 192.168.0.0/24
                  Too many (9) levels of IP recursion truncating
1.1.1.2/32, epoch 0
  1 RR source [no flags]
  recursive via 1.1.1.3
    recursive via 1.1.1.4
      recursive via 1.1.1.5
        recursive via 1.1.1.6
          recursive via 1.1.1.7
            recursive via 192.168.0.2
              recursive via 192.168.0.0/24
                attached to GigabitEthernet0/0
  
And for IOS XR according to the documentation it limited to 128 and can be configured with recursion-depth-max command in the range of 5 to 16.