diff --git a/modules/kamailio/config/kamailio.cfg b/modules/kamailio/config/kamailio.cfg
index bc652675..005814fe 100644
--- a/modules/kamailio/config/kamailio.cfg
+++ b/modules/kamailio/config/kamailio.cfg
@@ -298,6 +298,11 @@ request_route {
         }
         $dlg_var(du) = $du;
         route(SET_TIMERS);
+        # Tag initial INVITE with the original source IP so downstream Asterisk
+        # can match IP-based trunks via "match header" on X-Forwarded-For.
+        if (is_method("INVITE") && !has_totag()) {
+            route(ADD_X_FORWARDED_FOR);
+        }
         route(RELAY);
     } else {
         # what could happen here ?
@@ -788,13 +793,14 @@ route[SET_CDR_VARS] {
 } # end route[SET_CDR_VARS]
 
 # -----------------------------------------------------------------------------
-# route[ADD_X_REAL_IP]
-# add header X-Forwarded-For
+# route[ADD_X_FORWARDED_FOR]
+# Add X-Forwarded-For header with the source IP so downstream Asterisk can
+# match IP-based trunks even when the INVITE arrives from this proxy.
 # -----------------------------------------------------------------------------
-route[ADD_X_REAL_IP] {
-    remove_hf("X-Real-IP");
-    insert_hf("X-Real-IP: $si \r\n");
-} # end route[ADD_X_REAL_IP]
+route[ADD_X_FORWARDED_FOR] {
+    remove_hf("X-Forwarded-For");
+    insert_hf("X-Forwarded-For: $si\r\n");
+} # end route[ADD_X_FORWARDED_FOR]
 
 # -----------------------------------------------------------------------------
 # branch, onreply, failure Route definition
@@ -1050,6 +1056,12 @@ route[HANDLE_ALIAS] {
     if ($rc == 1) {
         if ($shv(debug) == 1) xlog('L_WARN', "[DEV] - $ci $rm-$cs - handle_ruri_alias returned 1, doing RELAY \n");
         route(SET_TIMERS);
+        # Same X-Forwarded-For tagging as the main inbound path: when the RURI
+        # carries an ;alias= param, HANDLE_ALIAS shortcuts to RELAY and skips
+        # the main flow, so we must add the header here too.
+        if (is_method("INVITE") && !has_totag()) {
+            route(ADD_X_FORWARDED_FOR);
+        }
         route(RELAY);
     }
 } # end of route[HANDLE_ALIAS]
diff --git a/tests/02_kamailio_routing.robot b/tests/02_kamailio_routing.robot
new file mode 100644
index 00000000..7985763c
--- /dev/null
+++ b/tests/02_kamailio_routing.robot
@@ -0,0 +1,51 @@
+*** Settings ***
+Library   SSHLibrary
+
+*** Test Cases ***
+Kamailio config defines ADD_X_FORWARDED_FOR route
+    [Documentation]    The route that injects the X-Forwarded-For header on
+    ...                inbound INVITEs must be defined in the runtime config.
+    ${output}  ${rc} =    Execute Command
+    ...    runagent -m ${module_id} podman exec kamailio grep -c '^route\\[ADD_X_FORWARDED_FOR\\]' /etc/kamailio/kamailio.cfg
+    ...    return_rc=True
+    Should Be Equal As Integers    ${rc}    0
+    Should Be Equal As Integers    ${output}    1
+
+Kamailio config inserts X-Forwarded-For with source IP
+    [Documentation]    The route body must remove any existing header and
+    ...                insert one carrying the source IP variable ($si).
+    ${output}  ${rc} =    Execute Command
+    ...    runagent -m ${module_id} podman exec kamailio grep -E 'insert_hf\\(.*X-Forwarded-For:[[:space:]]*\\$si' /etc/kamailio/kamailio.cfg
+    ...    return_rc=True
+    Should Be Equal As Integers    ${rc}    0
+    Should Contain    ${output}    X-Forwarded-For
+
+Kamailio main flow invokes ADD_X_FORWARDED_FOR on initial INVITE
+    [Documentation]    The main inbound branch (direction=in) must call the
+    ...                route guarded by is_method INVITE and !has_totag.
+    ${output}  ${rc} =    Execute Command
+    ...    runagent -m ${module_id} podman exec kamailio grep -c 'route(ADD_X_FORWARDED_FOR)' /etc/kamailio/kamailio.cfg
+    ...    return_rc=True
+    Should Be Equal As Integers    ${rc}    0
+    # Two call sites: main flow + HANDLE_ALIAS shortcut
+    Should Be True    ${output} >= 2
+
+Kamailio HANDLE_ALIAS shortcut also tags X-Forwarded-For
+    [Documentation]    When handle_ruri_alias() shortcuts to RELAY, the
+    ...                header tagging must still run, otherwise INVITEs with
+    ...                an ;alias= param reach Asterisk without the header.
+    ${output}  ${rc} =    Execute Command
+    ...    runagent -m ${module_id} podman exec kamailio awk '/^route\\[HANDLE_ALIAS\\]/,/^} # end of route\\[HANDLE_ALIAS\\]/' /etc/kamailio/kamailio.cfg
+    ...    return_rc=True
+    Should Be Equal As Integers    ${rc}    0
+    Should Contain    ${output}    route(ADD_X_FORWARDED_FOR)
+
+Kamailio kamcmd reports the running config without parse errors
+    [Documentation]    A loaded broken config would have prevented the
+    ...                container from staying up; this asserts kamcmd still
+    ...                answers, confirming the runtime accepted the cfg.
+    ${output}  ${rc} =    Execute Command
+    ...    runagent -m ${module_id} podman exec kamailio kamcmd core.uptime
+    ...    return_rc=True
+    Should Be Equal As Integers    ${rc}    0
+    Should Contain    ${output}    uptime