diff --git a/ipaserver/install/dsinstance.py b/ipaserver/install/dsinstance.py
index 9c15d721f..892057a5d 100644
--- a/ipaserver/install/dsinstance.py
+++ b/ipaserver/install/dsinstance.py
@@ -1303,4 +1303,8 @@ def write_certmap_conf(realm, ca_subject):
     shutil.copyfile(
         os.path.join(paths.USR_SHARE_IPA_DIR, "certmap.conf.template"),
         certmap_filename)
-    installutils.update_file(certmap_filename, '$ISSUER_DN', str(ca_subject))
+    installutils.update_file(
+        certmap_filename,
+        '$ISSUER_DN',  # lgtm [py/regex/unmatchable-dollar]
+        str(ca_subject)
+    )