/usr/share/opensips/db_berkeley/opensips/dr_carriers is in opensips-berkeley-module 2.2.2-3.
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 | METADATA_COLUMNS
id(int) carrierid(str) gwlist(str) flags(int) state(int) attrs(str) description(str)
METADATA_KEY
0
METADATA_READONLY
0
METADATA_LOGFLAGS
0
METADATA_DEFAULTS
NIL|NIL|NIL|0|0|''|''
|