diff --git a/testing/btest/scripts/base/frameworks/logging/path-func-column-demote.zeek b/testing/btest/scripts/base/frameworks/logging/path-func-column-demote.zeek
index 7b256da666..40f8043801 100644
--- a/testing/btest/scripts/base/frameworks/logging/path-func-column-demote.zeek
+++ b/testing/btest/scripts/base/frameworks/logging/path-func-column-demote.zeek
@@ -9,6 +9,9 @@
 @load base/protocols/conn
 @load base/frameworks/notice
 
+# Don't automatically treat private address space as local here so we filter
+# precisely on a single local prefix:
+redef Site::private_address_space_is_local = F;
 redef Site::local_nets = {141.142.0.0/16};
 
 function split_log(id: Log::ID, path: string, rec: record {id:conn_id;}): string