/etc/iproute2/rt_scopes is in iproute2 4.9.0-1+deb9u1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 | #
# reserved values
#
0 global
255 nowhere
254 host
253 link
#
# pseudo-reserved
#
200 site
|